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No Weld Grinder and Sander Plans (NWGS) Page - 2 -

Copyright 2007 Midwest Knifemakers Supply, LLC www.USAknifemaker.com No part of this document may be copied for distribution in paper formor electronic form for any reason with out the express written permission of Tracy Mickley at Midwest Knifemakers Supply, LLC

The design requires no welding and once constructed you will find the NWGS is exceptionallysolid and vibration free. I honestly dont think welding is needed but if you want to weld it, you canvery easily. 1/3 of builders weld their grinder as the design allows for quick and easy welding.

Getting Started:

Safety first.

WARNING!Possible serious injury or death could result in your use of this power tool! I am not an

engineer, machinist or expert in power tool design. I believe this design to be basically safe inmaterials and construction methods. I have extensive experience with grinding and sanding and knowthese activities to be very dangerous. You should understand that grinding and sanding is a dangerousoperation and you should seek training if you have no experience with a power grinder or sander. Iknow several very experienced metal working people that have been very seriously injured using theirgrinder.

The shop tool that seems to cut or scrape me the most often isnt the grinder, its the drill press.Secure or clamp the pieces you are drilling. Drill presses or hand drills have a lot of torque, more thancan be held some times.

Always wear ear and eye protection. Consider wearing a heavy leather shop apron whileoperating your grinder sander.

These plans assume the individual constructing the NWGS has at least a working knowledge ofpower tools and can safely operate a completed grinder.

This design is for a 1750RPM or 3450RPM motor with a 2 to 4 drive pulley. See AppendixC Motors for a formula to calculate SFPM (surface feet per minute) speed.

Contact wheels and aluminum drive wheels all have bearings and high speed operationgenerates a lot of heat. Small contact wheels are often unable to shed heat fast enough and the bearingsare destroyed by the heat. Run smaller contact wheels at lower speeds.

All bearing wear out. Regularly inspect and replace any worn bearings. Look for lubricantleakage from the sealed bearing or rough action. Bearings are inexpensive compared to a critical shopaccident if one disintegrates at high speed.

Always wear a respirator when grinding or sanding! Metal dust in your lungs does damage.

Some metals outgas heavy metals while grinding and can cause heavy metal poisoning. Some exoticwoods can cause allergic or toxic reaction that can cause death while sanding. I always wear arespirator while grinding or sanding. Note, wear a respirator that is rated for particle and toxic fumes.These respirators cost anywhere from $25 to $40 with replaceable cartridges. Dust masks block onlylarge particles of dust and should probably not be used but are better than nothing.

Beware of the open drive belt! OSHA regulations require a powered belt to be entirelyenclosed in a commercial or business operation. We provide no plans for a belt drive cover as we are
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not in a commercial environment. I would recommend you cover the belt drive with some type ofenclosure. A simple 3 sided wooden box with cut outs for the two shafts with enough length andheight is all that is needed.

What we can not support or help you with:

Wiring the motor and switch will be up to you. We will provide some very basic information inthe appendix on motors but we can not provide any assistance on wiring or hooking up your motor.Dont despair, it is fairly simple to hook up a motor and if you are not familiar with installing orwiring a motor, buy yours from a store that will help you with the connections. Check the supplierslisting appendix for help with purchasing a pre-wired motor from Wayne Coe.

We cant help you with any home made contact wheels. Contact wheels turn at incredibleRPMs that have very high centrifugal forces. This is not a place to experiment. A contact wheel thatexplodes during use can seriously injure, blind or kill you. Dont try and save a few dollars here. Itsnot worth your eye sight or life.

Wed be interested in hearing about your design modifications but we cant really consult onthem.

If you need help, go to www.KnifeDogs.com. There are a lot of members there withexperience in building grinders of all kinds and they will most likely have answers for you!

Membership in KnifeDogs.com is free.

Overview - Review the plans and shop for parts

Review the entire plans and create your materials shopping list. A complete materials list hasbeen provided for you in the appendix. You may not want to make every tool attachment for yourgrinder/sander. Purchase your materials locally and place your orders for those parts you can not findin your area. Most people will have to order their contact wheels and idler and power wheels throughone of our listed sources. If you have a lathe, you can machine your own aluminum idler and drive

pulleys.You will have to plan your motor purchase. You will need to decide if you are going to make asingle speed or multiple speed grinder/sander using pulleys or possibly a variable speed power sourceusing controllers and different motor types. We have 5 pages of information in the appendix to helpyou with this decision. A new 1 &1/2hp motor was around $180 when this grinder design was beingresearched. I bought a used motor for $75 by shopping around the local motor repair shops. I bought anew motor for $180 from the local farm supply store. Both were TEFC, 1 & 1/2hp single phasecapacitor start motors. It pays to shop around.

Contact wheels range in price from $45 to $300 for a huge 14 wheel. Many people dont use acontact wheel at all and simply use a flat platen for their grinding or a slack belt sander set up. In thosecases you just need some additional aluminum idler wheels.

I would advise you to build the 8 or 10" contact wheel tool attachment initially. You can addon several other tool bars as you need them later. I use the 8 wheel on my grinder more than anyother attachment. I think you will too due to its flexibility of use in various applications. The beautyof the NWGS design is that it will grow with you as your needs grow and it will be very inexpensiveto add an entirely new capability to your grinder/sander. Of course you can go whole hog and buildevery available tool attachment there is and then design some of your own. It will be easy to do withthe techniques in the plans and the supplier listings we provide.


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Midwest Knifemakers Supply, LLC atwww.USAknifemaker.comwill carry nearly all of theparts you need (and many of the tools) in various kit forms or individual parts to complete your entireNWGS. Every part with the exception of the contact wheels and aluminum idler and power wheels canbe found locally in a community of nearly any significant size at all at the local hardware store, motorsupply and metal supply businesses. I live in a town of 45,000 people and found at least 3 of each type

businesses that would supply the basic parts I needed in one afternoon of shopping my supply list.

Overview - Get organized and cut materials

Clear a large enough work space to lay out all of your parts. Taking the time to lay out yourparts in an organized fashion will save you an hour or two of construction time.

Cut your materials to size and using your marking pen, write notes on the parts to identify whatthey are and the orientation such as top, bottom, front back. Chamfer all outside edges and de-bur allinside edges. A power tool can be used to slightly chamfer the outside cut edges but cleaning up theinside edges is usually a manual process using a hand file or de-bur tool. If you dont have a metal

band saw and hand cutting several cuts with a hack saw doesnt appeal to you, every metal supplierwill cut your purchase to your size specifications for a small cut charge. My local metal suppliercharges nothing for the first cut and $3 a cut after that.

It can not be over emphasized how important it is to label each of your parts at every step ofthe construction process. Write directly on the part the orientation, hole sizes any other notes that youthink will help you keep things clear.

Cut your pipe square! You will need to measure from several sides of the end cut to measureand mark for drill holes. If your cut isnt square, your through holes will not line up. I built several

prototypes of this grinder/sander. Every time I had a set

of through holes that didnt line up I found I hadn'tchecked to make sure it was square. This simple thingwill cause you problems until you get serious aboutsquare end cuts. This design isnt high precision by anymeans but it does require you to pay attention to each cutyou make. Thesepictures show a pipethat was not cut squareone way but it wassquare when measured

another way. Always measure for square two ways! Through holes

measured from this cut simply will not match up. Check at least twosides when inspecting the cut.

Overview - Drill and assemble your frame

Drill your materials and assemble following the order laid out in the plans. Note that accuratemeasurement of any hole locations are important or the NWGS will not fit together properly.
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If some of your holes dont align enough to allow the bolt to connect the parts, try drilling aslightly larger hole in the affected parts. You can over size holes slightly larger to get parts to bolttogether. If you still cant get the through holes to line up after over sizing by the hole up to 1/8, I'dsuggest scrapping the part and make a new one. Cut your ends square and this won't be a problem.

All of the bolts used are 3/8-16 grade #2 bolts with nuts, washers and lock washers. These areoften sold by the pound at most hardware stores. There is no reason to buy higher grade bolts such as 5or 8 also commonly found in bulk. Grade 5 and 8 bolts are designed for high load and stressenvironments and they often cost 2 to 5 times more than commonly found grade 2 bolts and nuts.There is no significant load or stress loads in this design that requires expensive fasteners.

Using a carpenter square, set your measurement and then scribealong the ruler edge. Flip it to the other edge and scribe again.

In this picture, you can see two horizontalscribe lines and one vertical. Split the difference inbetween the horizontal lines and you will have yourtrue center.

Overview - Mount the motor and power train

Locate and place your motor to fit your belt and pulleys. (Your motor must rotate counter clockwise!)Allow some movement in the motor mount to tighten the belt for proper tension and to adjust fornormal wear. Normally this is simply getting the belt in place and drilling over size mounting holesthat allow for some adjustment. Most motor mounts have slots that allow movement for this.

Overview - Wire your motor

Wire your motor and switch. Make sure you use a good ground contact. If your motor canoperate in clock wise (CW) or CCW (counter clock wise) make sure it operates counter clock wise.


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Overview - Shake it down and make adjustments

Double check your frame and motor wiring. Double check every single nut and bolt is tight.Place a tool bar in the tool arm socket and mount a belt. Wear your safety gear. Start the grinder on theslowest speed checking for vibrations, loose parts or other problems that may been overlooked. At the

lowest speed is when you should verify that all of your tool attachments are working properly. Onceyou have shaken it all down, make any needed adjustments. You will almost certainly have to add orremove a few washers for wheel and belt tracking alignment. Keep machinery bushings next to thewheels. These machinery bushings have the right size ID and OD to fit the bearings and not bind onthe wheel. After your adjustments, try grinding or sanding some scrap materials, again testing everyattachment.

At this point, it would be normal to have to adjust the belt tension between the motor and drivepulley due to slippage. It would also be normal to have to adjust the tension spring at this point bycutting or stretching it. A belt that is loose wobbles and slides to one side or the other when beingused. A belt that is too tight bogs down the motor and stretches the belt so that it will not track

properly. It is almost impossible to get your belt too tight with this design. 95% of tracking issues witha new build are the result of not enough belt tension. Note: If you are having issues with the belt nottracking just right, try another belt, especially a different brand if you can before making anyadjustments.

Move it up to half speed and try every thing again. If it all goes well, try everything at fullspeed to make sure it all works properly. Testing it now might save you a serious injury later whenyou are less attentive to the machine and more focused on your project.

The second proto-type NWGS is shown here.Note that there are some extra holes drilled inthe various pipes as a result of R&D andshould not be duplicated. I have this mountedto 2 layers of plywood. The tool arm frommy KMG grinder has two wheels, a 4 and a2. I simply flip the tool bar over to use the 2wheel. Note that the grinder is actuallyrunning full speed in this picture.


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The picture to the right shows the motor side of the tensionarm. A tracking wheel mount swivels on its two brackets.The tracking adjustment knob swivels the tracking wheelmount to adjust the track of the abrasive belt. You will needto use machinery bushings on either side of the wheel.

These are narrow rimmed bushings with ID. Thesebushings allow you to snug up the bolt/spindle assembly sothe wheel doesnt hunt back and forth.

The belt side of the tracking wheel

mount is shown in this picture. Thearrow points to part of the mount that isbasically a lever that is moved in or outvia the tracking adjustment knob. Whenthe tracking adjustment knob is turned, itmoves the lever part of the wheel mountin or out, which in turn angles thetracking wheel, adjusting the track of thebelt.

Tracking Block AssemblyRefer to the CAD drawings: Tracking Block Construction, Tracking Block Bracketsand TrackingAdjustment Pivot Block. Alternate Bracket construction: Bend 4 of 1/8x1 flat bar to 90degrees,mark and drill holes accordingly. This method may be easier than cutting a piece of tube into

brackets. Plans update: We recommend you simply bend 1/8"x1" flat bar into "L" brackets here.The following assembly steps assume you have cut all pieces to length and drilled all holes according

to the CAD plans.

Assembly Step 1 Refer to CAD drawing Order of AssemblyAfter you have drilled the holes in the base mount tube, bolt the base tube to your bench or a

base of plywood using 3/8 bolts.For the portable plywood base, glue and/or screw a couple thick pieces of plywood together

in 30x30 square. Mark your base tube and motor locations and drill the mounting holes. Counter


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sink the connecting nuts on the bottom so your platform will sit flat on your bench. You may have tocut the bolts to size. Refer to theBase Mountdrawing.

Assembly Step 2 Refer to CAD drawing Order of AssemblyAttach the Tool Arm Socket tube to the top of the base tube. Refer to the Tool Arm RestCAD

drawing.

Assembly Step 3 Refer to CAD drawing Order of AssemblyAttach the upright columns to the base tube using 4ea 3/8 x 6 bolts and washers. The

longer column goes to the back. Refer to the Front and Back Columnsdrawing.

Assembly Step 4 Refer to CAD drawing Order of AssemblyAttach the tool bar holder horizontally to the two uprights using 4ea 3/8x 4 1/2 nuts, bolts,

washers and 4ea 1x 4 1/2 straps. Approximately 1 inch of the tool bar holder tube should extend pastthe front vertical column. The tool bar tube should also be mounted approximately 1 below the top of

the shorter column. The bolts and

straps form a clamp to hold the tube inplace. See placement in the picture tothe left.

Refer to the Tool Bar Holderdrawingand Tracking Blocks/Strapsdrawing.Note: Placement is not critical here.Just mount the tool bar tube as high asyou can on the short upright and keepit horizontal (square to the uprights). Ifyou mount it too low, you may have a

bench clearance problem with theslack belt and platen attachments.

Assembly Step 5 Refer to CAD drawing Order ofAssembly

Attach the Tension arm to the rear vertical column usinga 3/8x 3 bolt. This tension arm will swivel so use a couple of

washers between the vertical column and the tension arm with adrop of oil or grease. Since this part will rotate often, to stop thenut and bolt to from unscrewing, double nut the bolt or useLoctite thread locking fluid. If you are going to use Loctitethread locking fluid, do this as the very last step after you havemade all the adjustments you need to during your shake downtesting. Refer to the Tension Armdrawing.


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Assembly Step 6 Refer to CAD drawing Order of AssemblyBolt the tracking assembly to the tension arm as pictured above. Note how the tracking assembly isbolted slightly off center of the tension arm and is slightly closer to the tracking wheel side. Thetracking adjustment knob is threaded on the motor side of the tension tube with the wheel side drilledlarger to make it a through hole. Refer to the 2 Tracking Blockdrawings. Alternate Bracket

fabrication: Mounting brackets can be fabricated from 1/8 x 1 flat stock bent 90 degrees and 2 longfor each end. This might be easier than cutting a square tube into mounting brackets.Assembly Step 7 Refer to CAD drawing Order of Assembly

Attach the tension arm spring using bolts and large washers or eyebolts to back ends of boththe tension arm and the base tube. Attach the spring. The tension provided by the spring when an

attachment and abrasive belt is mounted should be quite stiff.In this picture, you can see a common door spring doubled over andattached to the tension arm and base tubes by a 3/8 bolt. Also note thepillow block bearings are mounted with the drive shaft held in place bylocking collars next to the bearings. These locking collars prevent the shaftfrom sliding side to side in the bearings. We suggest you use Power Twist

Link to simplify your belt selection. These link belts can be easilyadjusted to size by adding or removing links. These belts run quite a bitsmoother and quieter than a traditional V belt. Also, we strongly suggestyou use the triple pulley system to give you three different speeds insteadof just one speed with a traditional single pulley set up. To change speed,with the motor off, simply move the belt to the smaller pulley manually onthe drive shaft first and then to the larger, matching pulley on the motor orvice versa.

Changing speeds takes just seconds after doing it once or twice.

Assembly Step 8 Refer to CAD drawing Order of Assembly

Attach the pillow block bearings to the base tube. Insert the 14 drive shaft into the bearings. Itmay be necessary to oil or grease the shaft to get it to slide smoothly through the bearings. (The shaftshould already have keyways cut for the pulley and drive wheel. See the appendix for Cutting aKeyway. There is no CAD drawing of the shaft.) Using locking collars, install the locking collars onboth sides of the bearings so the shaft doesnt move side to side in use. Do not tighten yet. Attach thedrive wheel and drive pulley. Adjust the shaft side to side so the drive wheel is in line with the tensionwheel and contact wheel. When you have every thing lined up, tighten the locking collars and the setscrews in the pulley and drive wheel. Some bearings have a set screw built in, these work fine also.

Assembly Step 9 Refer to CAD drawing Order of AssemblyScrew in the tracking adjustment knob and the tool bar knob.

Assembly Step 10Mount your motor to the wooden base or bench. Install the

drive belt and tighten the belt by moving the motor forward in themounting slots. Bolt down the motor to keep a snug tension on thebelt. Keep in mind the belt will stretch with use and you probablyhave to tighten the belt again by moving the motor forward after a


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few hours of use. If you have a Power Twist Link belt, you can remove a link. When you mount themotor, use a square to ensure the drive belt and square to both the motor and drive shaft pulleys.Having the motor canted wastes power, increases friction, heat, noise and you will wear out your drivebelt prematurely. Your drive belt should last for a very long time. If it is too lose, the belt will slipoften and glaze over. A glazed belt will soon have to be replaced.

Step 10Double check your nuts and bolts to make sure they are all tight. Insert a tool arm attachment

into the machine, mount a belt, pull the tool attachment forward to put tension on the belt and tightenthe tool bar knob. Stand to the side and start the motor. Be ready to quickly adjust the tracking knob tocenter the belt on the wheels. Be ready to quickly turn off the motor if something goes wrong.

In the picture to the left, a completed grinderis shown with the slack belt attachment in

place. Note there are two different sizes ofcontact wheels on the slack belt for grindingdifferent radius contours. The tool table is notattached in thispicture. In thepicture to theright, you can seea tool rest socketpipe attached tothe base mountpipe.

Fine Tuning the AlignmentYou will almost certainly have to add a few washers and adjust some bolts here there to get all

of the wheels to align evenly across the length of the belt. In every case you will have minimum of 3wheels and often 4 wheels to line up. Get your power drive wheel and tracking wheels lined up firstand then dont touch them again. Each tool bar wheel will probably require some tuning also. You canstack any kind of washers you like as long as you use machinery bushings next to the bearings in the

wheels. If you use a typical ID washer next to the wheel, it will actually contact and be driven bythe wheel and not be snug in one position and will wobble. If you use one machinery bushing on bothsides of the wheel, you can usually stack any kind of washer next to the wheel as the single machinerybushing provides enough clearance. You want the bolt to hold the wheel snugly in place but the wheelshould be able to spin freely. The most common issue with new builds is there is not enough belttension. Make sure your spring pulls the belt tight!


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Tool Rest TableBuilding the tool rest is optional. It consists of three

moving arms that allow movement in all 3 dimensions. The toolrest table provides a flat surface to rest a work piece one while

pushing it into the grinder. It is most often used with the flat platenbut can also be used with any of attachment arms. There are 2drawings for constructing the Tool rest. In addition, there are 2examples of table rests in the drawings. Bolts are used in thedrawings but knobs can be substituted for faster positionadjustments.

Attachment tool arms:

Contact wheelsThe least complicated attachment tool arm is simply acontact wheel bolted to a 1.5x1/8 square tube. Thetube length should be approximately 15 in length. Themounting hole for the contact wheels listed in thesuppliers listing use a diameter bolt. Use a machinery

bushing (1/2 diameter ID,

narrow rim,14ga thick) on both

sides of all wheels next to the

bearings.These have just the

right size ID and OD to not bindagainst the wheels but touch onlythe bearing. There are no pictures

or drawings provided due to its simplicity of this attachment.

Slack Belt AttachmentThis is a fairly simple attachment to build. Refer to the CAD drawing

provided. Note you can use either steel plate or aluminum plate and bar stock inconstruction of this tool arm. You can use 2x2 aluminum idler wheels for boththe top and bottom wheels to keep costs down. I use 2 different radius rubber

contact wheels so I can use these for different contours during slack beltsanding. When your grinder is up and running, grind off those protruding squarecorners you can see here in the picture.


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Flat Platen Attachment

This attachment is slightly more complex than the others but it is still a very simple build.There are two CAD drawings for this tool assembly. Refer to theFlat Platen Attachment Plateand the Platen Attachment Partsdrawings for detailed construction notes. These parts can be

constructed in either steel or aluminum.

This picture shows the back of the platen. You can see the slots cutinto the angle iron allow the platen to be moved in and out tobetter match the belt.

You might be surprised at how fast the actual platen surface willwear and become uneven. Some people use hardened tool stoolsuch as 01 for their platen surface. Heat treating 01 tool steel isntdifficult but is beyond the scope of these plans. I use Pyrex glassthat I epoxy on with JBWeld. Nearly any glass store will cut you a

piece of fire place glass for a small charge. If you simply cant findit locally we have Pyrex cut to size onwww.USAknifemaker.com.You can find others selling similar material on the internet called

Pyra-ceram. It is all basically low thermal expansion glass. The advantage to the glass face on theplaten steel is: it is very hard and wears much slower than steel, it is very flat compared to steel and itruns cooler when grinding. The disadvantage is: it can come loose and shatter creating a verydangerous situation. I know several knife makers this has happened to. Fortunately, none wereseriously hurt because they were wearing eye and other protection and they were very lucky. If you aregoing to use fire place glass as a platen surface, consider adding a small ledge or support on thebottom of the glass to hold the glass in place if the epoxy fails. When using epoxy to attach the glass,dont clamp it during the cure. If you clamp the glass, it will bend slightly putting it under stress andthen it will crack when grinding due to heat expansion. Simply mix up the epoxy (I suggest JBWeld, ittakes high heat better than most), slather it on and push the glass onto it centered and then let it cure.The sharp edges of the glass can be ground off just like grinding metal. Round each edge slightly tokeep the belt back side from getting cut. A sharp edge is going to wear smooth fairly quickly fromnormal use but you dont need to waste a couple belts while it is breaking in. You will probably getsome static electricity coming from this set up. Simply spray a little StaticGuard (or other staticreducing spray) laundry spray type on the inside of the belt. It knocks the static electricity way down.
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Appendix A Master Materials List revised 12/6/07Materials List (assumes you build all tool arms and table rests)No margin for squaring up cuts is reflected in this materials list. There is a great deal of tolerance in the actual part

length. Nearly every part can be just a little shorter than the plans call for and it will still work. If you prefer to be

exactly to plan, consider adding a slight increase in parts length to allow for a margin of error in squaring up your cuts.

Again, most parts can be slightly longer or shorter than the plans call for and it will work out just fine.

Metal:Qty Item1.5 4 square pipe 1/8 thick2.75 2 square pipe 3/16 thick3.75 1.75 square pipe 1/8 thick (substitute 1.5" square tube if unable to find 1.75")8 1.5 square pipe 1/8 thick3.75 1x1/8 flat stock3.25 2x3/8 flat stock* (*only a 2 tool table is allowed for, if you want a1.25 4x3/8 flat stock bigger tool table, increase your materials list to reflect that.)1 1.75 x 1.75 x 1/8 angle iron (2x2 is OK also)14 5/8 round stock cold rolled

Connectors:Qty Item4 6 x 3/8 bolts14 4 x 3/8 bolts11 3 x 3/8 bolts19 1 x 3/8 bolts2 5 x bolts4 3 x bolts14 nuts for bolts41 nuts for 3/8 bolts45 washers with ID (inside diameter)

63 washers with 3/8 ID14 Machinery bushings ID 14ga

Wheels:1 Tracking Wheel1 Drive Wheel bored for 5/8 shaft4 2x2 idler wheel (suggest sub 2 or 3 contact wheels)1 8 or 10"contact wheel

Other:2 Pillow block bearings for 5/8 shaft1 knurled knob 3/8-16 for tracking adjustment-can sub long bolt bend to 90degrees1 4 bump knob 3/8-16 for tool arm holder - can sub long bolt bend to 90degrees

1 Common door springPower Train:

1 Motor recommend 1 1/2HP TEFC Heavy Duty1 wiring supplies: switch, switch box, wire nuts, wire, electrical tape1 pulley for motor shaft recommend 3 step pulley system1 pulley for drive shaft of grinder recommend 3 step pulley system1 drive belt recommend 2Power Twist link drive belt by Fenner1 mounting platform recommend mounting onto 2 layers of plywood


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Appendix B Suppliers Listing

Suppliers Listing

All of the following is available fromwww.USAknifemaker.com:

Abrasive Belts, Contact Wheels, Idler Wheels, Power Drive Wheels, Drive ShaftRod, Pulleys, Step Pulleys, Power Twist Link Belt, Key Material, MeasuringTools, Carpenters Square, Scribes, Layout Fluid, Pillow Block Bearings, MetalSquare, Cutting/Drilling oil, Drill Bits, Unibit drill bits, Bolts, Nuts, Washers,Machinery Bushings, Pyrex. We also have most of the metal used in these plans.

In addition:

Knife Making books, videos and a full line of knife making supplies.

At:Midwest Knifemakers Supply, LLC1350 Lake Street

North Mankato, MN 56003Phone 507-720-6063 Monday through Friday 8:00 to 5:30 Central TimeFax 507-720-6305www.USAknifemaker.com

email:[email protected]

Aluminum idler and power wheels, contact wheels, motors, bearings, pulleys

Rob FrinkBeaumont Metal Works362 Beaumont Rd.Columbus, OH 43214Phone:(614) 291-8876 (9-5 EST M-F)

FAX 614-261-0094

www.beaumontmetalworks.com
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Contact wheels

Burr King1220 Tamara LaneWarsaw, MO 65355

Phone Numbers(660) 438-8998(800) 621-2748

Fax Number(660) [email protected]

www.burrking.com

Contact Rubber Corp.8635 198th AvenueP.O. Box 97Bristol, WI 53104Telephone: 262-857-2361Fax: [email protected]

Metal, drive shaft material

Check in your yellow pages for local supplier, often it is under scrap metal dealers.Most home centers such as Lowes or Home Depot have a mild metal rack and this willalmost always have 5/8 cold rolled round stock as part of their assortment.

www.onlinemetals.com

Motors and other miscellaneouswww.surpluscenter.com

Wayne Coe.Wayne is a retired attorney turned full time Artist Blacksmith. He teaches classes on

Blacksmithing and building No Weld Grinders. If you go to a weekend class of Wayne's, youleave with a completed, running grinder. He also sells motors and will pre-wire a motor for youon request. I have bought a motor from Wayne myself and highly recommend him. Wayne canbe contacted at www.KnifeDogs.com. If you need a motor and can't find one locally or wantone all wired for you, contact Wayne. His direct email is: [email protected]
http://www.midwestknifemakers.com/http://www.midwestknifemakers.com/http://www.midwestknifemakers.com/mailto:[email protected]://www.burrking.com/mailto:[email protected]:[email protected]://www.contactrubber.com/http://www.contactrubber.com/http://www.onlinemetals.com/http://www.onlinemetals.com/http://www.surpluscenter.com/http://www.surpluscenter.com/http://www.surpluscenter.com/http://www.onlinemetals.com/http://www.contactrubber.com/mailto:[email protected]://www.burrking.com/mailto:[email protected]://www.midwestknifemakers.com/


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Drive belts, nuts, bolts washers, bearings, pulleys, motors

Tractor Supply Co (TSC)

Ace Hardware Store

Most any farm supply store.

Knobs, bearings, drive shaft, keyway stock, abrasive belts, motors

MSC Industrial www.mscdirect.comEncowww.use-enco.com
http://www.midwestknifemakers.com/http://www.midwestknifemakers.com/http://www.midwestknifemakers.com/http://www.mscdirect.com/http://www.mscdirect.com/http://www.use-enco.com/http://www.use-enco.com/http://www.use-enco.com/http://www.use-enco.com/http://www.mscdirect.com/http://www.midwestknifemakers.com/


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Appendix C - Motors, basic information

One of the problems with making your own equipment is that there are so many kinds ofmotors and the choices are so confusing its just too much work to determine what you needfor a project. We are going to give you just the basics here to help you make a better choice for

your power source.Motors operate in specific direction,either clock wise (CW) or counter clock wise

(CCW). Most motors can operate in either direction and are often noted as CW/CCW orDUAL. Make sure your motor operates in CCW or counter clock wise. This is always stampedon the case or ID plate. Single direction motors are usually cheaperthan multi-direction motors.

Motors come in all different RPMsor rotations per minute(speed). You want a motor that operates at 1725 or 1750 RPMs or3400 or 3450RPM. These are very common speeds for a motor andthis speed range is what your NWGS was designed for.

Motors are rated in HP or Horse Power. This isnt a greatway to measure a motor since every one seems to do it differently.Some motors are rated for peak horse power, some are rated underload, some are rated with out a load. Add to that some motors are lessefficient than others due to construction, materials and design. Likemost things, you get what you pay for. For our purposes, we want a motor that is at least 1hp.This is the absolute minimum and even then you will probably be able to slow or even stop theNWGS under heavy use. Plan on using a 1 1/2hp or even better a 2hp motor if you can find onecheap enough. You will find that the bigger the motor in HP, the more expensive it is.

Motors may be better rated by the amperage they draw under load. Below find a typical rangeof amperage vs HP vs 110v vs 230v. Note that the 230v(220v close enough) is generally moreefficient.

Calculated HP AMPS at 115v AMPS at 230v

1 13.0 - 9.3 6.5 - 4.6

1 1/2 19.5 - 13.9 9.7 - 7.0

2 25.9 - 18.5 13.0 - 9.3

Note that some motors are more efficient than othersin converting electricity tomotion. This isnt hype and shouldnt be overlooked. Naturally motors that are more efficient

are usually priced as little more. A more efficient motor will cost less to operate and may becheaper to operate in the long run than the initially lower priced motor. If the motor ismarketed as very efficient, than you just have to take the manufactures word for it as there isno consumer report ratings available for motors.

Motors come in different frames and styles. Here you have a lot more flexibility.We want an inexpensive motor that fits our needs. We are building a grinder on a budget. Youwant to make sure the shaft of the motor is 5/8 in diameter and the shaft is long enough to


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mount a drive pulley. The method of mounting the motor is often an issue. The design of theNWGS calls for the motor to be mounted to the same base as the grinder so you will want amotor that has at least 4 bolt hole on the bottom of the motor. Some motors mount only to theface (area around the shaft) C Face or Face Mount and those cant be used unless you fabricatea mounting bracket. Youre on your own there, but it really isnt that hard to fabricate a bracket

if you come across a great deal on a C Face mount motor. Some motors can be face or basemounted and would be fine to use. Just keep in mind that dual direction or dual mountingoptions on a motor add to the cost of the motor. What you want is a base mount motor with a5/8 shaft.

Motors are open or enclosed. The degree to which themotor is enclosed varies. The better sealed or closed a motor is tothe environment, the more expensive it is. Open motors, or ODP(open drip proof) have open vents that are designed to direct theoccasional drip of water away from the interior. These are cheap butgetting an open motor is false economy. If you use an open motor,

expect it to short out or break down prematurely. If you are grindingmetal, you dont want an electrical motor filling up with metal dustshorting out against the case possibly electrocuting anyone that touches the metal motor case.Ideally you want a TEFC (totally enclosed fan cooled) motor. These are more expensive butthey are worth the expense. There are also Explosion proof and Wet Environment motors.These cost even more and this level of protection isnt needed but if you can find a good dealon one of these motors, by all means get it.

Motors come in AC or DC, 120v, 220v, 230v,240v and 480v and 1phase or 3phase .AC (alternating current ie like house current) motors operate on alternating current but so doDC (direct current) motors! Whats up? Motors are made for all kinds of applications. In yourshop you most likely have 110v AC 1 phase typical house current. You want a 110v AC 1phase motor. Look for things like Heavy Duty Use 110v AC 1ph or Farm Use AC 110V1ph. The voltage, phase, HP, RPM and rotation will always be stamped onto the motor IDplate attached to the motor. Shy away from any motors that dont have this basic information.House current is 1 phase. Industrial plants often use 3 phase power. You dont have that inyour house so dont buy a motor that uses only 3 phase power. Many motors can use 1 phase or3 phase power. You just have to wire them up a little differently.DC motors actually operate on AC current but are wired differently internally using powerfulpermanent magnets to produce their power. There are specific reasons for using a DC motorinstead of an AC motor. We are going to leave it at this. An AC motor is almost always quite abit cheaper than a DC motor. Get an AC motor. If you know the reasons a DC motor issometimes preferred over an AC, you dont need to be reading this. You want a 110V AC 1phase motor.

What if I have 220v (230v, 240v) poweravailable in my shop?Great! Your motor might be cheaper! In general, motors that use 220v 1 phase power arecheaper than dual volt motors or new 110v AC motors. If you have the option of using 220v inyour shop and you know you wont be moving your grinder to another location that does nothave 220v, you should use 220v. Why? Its more efficient to operate a motor on 220v than


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110v AC and lets just leave it at that with out getting into a bunch of esoteric electricalengineering debate.

Motors are just one speed unless you have a controller that varies the speed. Thatis expensive. Take the basic motor cost and double or triple it and you can have a variable

speed motor. I think they are worth it and I wouldnt grind knives with out a variable speedmotor after having used one for years. Our NWGS design is on a budget so we use a step downpulley system. Our design uses either a 3 step or 4 step pulley to change the SFPM (surfacefeet per minute) speed of the abrasive belt. You cant do quality work all at full speed ahead.There are a lot of times when you want to slow things down. Many woods simply burn at highspeed. Knife makers have to slow the belt down when they are working on the finishing polish.The least expensive way to slow things down is to use the step pulley system in our design.You have to stop the motor, move the belt over a notch or two and then start back up. Itprobably takes longer to write those sentences than it does in practice to actually change thebelt. For a lot more money, you can get a motor speed controller combination that allows youto control the speed from full blast to dead stop. Like most things, there are trade offs to this.

First it costs a lot more for a speed controller. Second, the slower you go, in many cases, theless torque the motor has. In other words it may go real slow but looses all the power to grindin the process. There are many different ways to control the speed of a motor and not everymethod suffers from the drawback.

DC motorsoften can be coupled with a voltage controller (not always) to slow thingsdown. There is some loss of torque and the motor starts to get jerky at very low speeds. I use a1 1/2hp DC motor on my KMG knife grinder. It has a Baldor 1 1/2hp DC motor with acontroller built into the base. It works just fine and I wouldnt be with out it. If it ever breaksdown, Ill replace it with a VFD drive and motor though. If you find a DC motor with acontroller at a good price, give it strong consideration. A variable motor will improve yourgrinding or sanding quality of work. You cant put any old DC controller and DC motortogether. The controller must be rated to meet or exceed the HP or power rating of the motor.

A word of caution is called for before we talk about AC controllers. You will see ACRouter speed controllers advertised for very little. These claim to slow down an AC motor ormake them variable speed and they do but at a high cost. You can burn your motor out withthese fairly quickly and I advise you to never use one.

AC motors with variable speed must be matched with a proper controllerandshould be bought as a set. Controlling the speed of an AC motor is fussy business and in mostcases, when an AC motor is slowed down, you lose a great deal of torque to the point where itis almost useless under speed. There may be a good deal to be had with a variable speed ACmotor but only if the controller comes with it and it is a proven combination.

There is another form of AC motor/controller combination that is called a VFD, orvariable frequency drive motor. These VFD combinations are almost always used with 220v.More correctly the controller is called the Drive and the motor is called a VFD type motor. (Iuse one of these on my disk grinder and I like it very much. When the DC motor on my grindergives out, I will replace it with a VFD motor.) In a nutshell, the VFD takes 1 phase power andelectronically turns this power into 3 phase power to drive a VFD motor which requires 3


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phases to operate. VFD motors are priced ridiculously cheap for their horse power rating whencompared to regular AC motors and especially when compared to DC motors. These VFDmotors are commonly used in industry, where most motors are so they are priced verycompetitively. A 2hp VFD may be priced at only a $100 dollars where a similar rate AC motormight be $175 and a DC motor might be $250! The catch is the controller is expensive. Expect

to pay at least $250 to $400 for a controller. The upside to these controllers is they are verysmooth and keep the torque of the motor quite high through nearly the entire speed range. AVFD motor set up is the most expensive option but to many it is the best option. They givevery smooth infinite speed control with very little loss in torque. The motors are electricallyefficient, very durable as they are generally constructed for an industrial environment and areusually protected against the elements quite well. Most are TEFC. The Drives however areusually open and sensitive to dust and will short out if kept exposed to excessive dust,especially metal dust. Ive lost one controller to this already. Just like motors, you can buydifferent levels of protection for the Drives at additional cost. Either keep your drive out of thedust cloud and protected or pay the extra for a sealed Drive so you dont loose it to prematureelectrical shorts. One last thing about Drives, you have to buy one that is rated at least twice

the horse power of the motor. I dont know why, you just do. If you have a 1hp VFD motor,you need a 2hp rated Drive. This isnt a hard and fast rule, its just a good practice. Ive heardof several people using a 2hp Drive on a 1 1/2hp VFD motor and doing just fine. It comesdown to a heat issue and shedding heat from process of converting 1 phase to 3 phase. Usingan over rated Drive gives you protection from burning out the electronics under heavy use andcurrent draw.

Ive recently heard about 110v Drives. I have no experience with them. Mosthousehold circuits are either 15 amp or 20 amp circuits. I can pop the circuit breaker with my 11/2hp DC motor by bearing down hard when I am flat grinding. 220v circuits are at least30amp and usually have room to spare when running a 2hp motor. When a Drive converts 1phase to 3 phase current, there is some loss in power to heat and the electrical conversionprocess. If you use a motor that is 1 1/2hp to 2hp on a 110v Drive, this could possibly draw alot more current than the house or shop wiring is designed for. This puts you at risk forconstantly setting off the circuit breaker or even worse, over heating the electrical wiring inyour house and starting a fire. Electricity is dangerous and you should know what you aredoing. If you dont understand what is going on, get some one that is professional or some onethat has experience with the motor and set up you are building.

Some other thingsyou should know about motors that might come up when you areshopping are:

A Split Phase motoris often used for applications that have a light load initially. It hasstart and run windings, both are energized when the motor is started. When the motor reachesabout 75% of its rated full load speed, the starting winding is disconnected by an automaticswitch. You will often hear a click in the motor when it kicks in or shuts down. I have an olddirect drive 1hp grinder that uses this and it works fine. These motors are used when a load isapplied after the motor starts and gets to speed.

ACapacitor Start motorhas a capacitor in series with the starting winding andprovides more starting torque with less starting current than the split phase motor. Thecapacitor start motor is used for loads which are hard to start like pumps, conveyers,compressors and other applications where the load is immediate. These motors have good


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efficiency and require starting currents of approximately five times full load current. This isntalways a problem but turning one of these motors on under load may pop a circuit breakerunder the right conditions. The capacitor and starting windings are disconnected from thecircuit by an automatic switch when the motor reaches about 75% of its rated full load speed.

So after all that what should you get for your motorif you want to vary the speed?

On a budget: use a 3 or 4 step pulley and get a single speed CCW 1 1/2hp AC 110vTEFC motor. You can try a 1hp but you will regret it if you do any heavy grinding at all. Usinga single drive pulley with a single slave pulley is the absolute cheapest way if you only need orwant one single speed. I am very impressed with how elegant and inexpensive a solution a 3step pulley setup is. Changing speeds by changing the belt from one set of pulleys to another isvery fast and easy usually 3 or 4 seconds is all it takes.

Middle of the road: A 1 1/2hp DC motor paired with a speed controller. Ive heard of

a lot of guys using tread mill DC motor and controller pulls or surplus that work well. Theseare open case motors and controllers and you will have to take some steps to protect the motorand controller from dust, especially metal dust.

Top the line (if you have 220v): A 1 1/2hp or 2hp VFD motor controller combination.If you havent worked with motors before, these are complex and you should work with adealer and pay a little more than taking a chance on going mail order or through eBay. Manydealers dont know much about VFD motors and controllers. Oddly, most electricians knoweven less. They simply can not believe that a little box changes 1 phase to 3 phase power.Make sure that your VFD motor controller is protected from metal dust or has a type 4 NEMAenclosure (sealed against dust) or it will be just a matter of time before it shorts out in a puff ofsmoke.


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Formula for SFPM (surface feet per minute):

Occasionally you will see talk about SFPM of a grinder. Here is a formula to calculate theSFPM of your No Weld Grinder/Sander

D=belt drive wheel diameter in inches

M=motor pulley diameter in inchesG=grinder pulley diameter in inchesRPM=Rotations per minute of the motorPi= 3.14*="times"/="divided by"(note the fixed number 12 converts inches into feet)

(Pi * D * RPM * M)/(12 * G)

which is reduced to:

SFPM = 0.262 * D * RPM * (M/G)

ExampleWe have a 4 belt drive wheel, a 1750 RPM motor, a 2 motor pulley and a 4grinder pulley.SFPM= .262 *4*1750*(2/4)SFPM=.262*7000*.5SFPM=917


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Appendix D Metal working tips and techniques

Drilling:Drilling metal, even mild steel, is made several times easier with sharp drill bits. You will only

use a few different sizes of drill bits during the construction of the NWGS, consider buying new bits in

just these sizes. Dull bits wander and wobble in the hole. The holes you drill will be less than roundand could force you to you drill over size holes to get your project to bolt together. For a few dollars indrill bits, you might save your self some head ache.

Always use cutting fluid when you drill metal. This will extend the life of your drill bits byseveral times and helps the drill bit cut cleanly for a more symmetrical hole.

Always use a center punch to locate the exact center of your hole. Drill bits wander whenstarting and you dont want to have to drill over size holes later.

Always use a smaller bit to drill a pilot hole initially and then re-drill it with the larger bitspecified in the plans. I use a 1/8 bit for my pilot holes. The pilot hole will keep your larger bit inplace and significantly reduce the effort needed to drill out the larger hole. If you have a small drillpress or hand drill, you may have to drill the same hole multiple times with progressively larger bits

until you get to the size of hole needed. A Uni-bit or step drill bit is perfect for this kind of drilling.Secure the part you are drilling in a vise or clamp. The larger a hole that is being drilled, the

more likely the drill bit is to grab the piece and force it to spin or helicopter.Adjust the speed of your drill to the size of hole you are drilling. Generally, the rule of thumb

is the larger the hole, the slower the speed of your drill. This is especially important when drilling the holes specified in the plans.

Occasionally a long chip curl will climb up the drill bit and then start to whip around. This is adangerous condition and you should either stop drilling and remove the chip curl or use a piece ofmetal to wipe it off the bit as it turns. Keep in mind that these chips are razor sharp.

Use a metal scribe or sharpened piece of metal to make your marks. A marker is too thick forprecision drilling and a pencil wont show clearly enough. In order to drill with precision, you need to

have sharp, thin lines to work with. If you dont have a scribe, use a sharpened nail or sharpened pieceof broken drill bit.

Wear safety glasses when drilling!

Measuring:Use a Carpenters Square to locate your holes, not a tape measure.Use a scribe to scratch your marks, not a marker or pencil.To accurately center a hole in a piece of square pipe, measure and scribe from both the top and

the bottom. Usually, the scribe lines will not match exactly so you will need to split the differencewhen center punching. This forces you to measure twice and verifies you have the exact center.

Cutting Metal:Make sure your cuts are square. You will be measuring from these cuts for hole placement and

the tolerances will not allow you the luxury of sloppy cuts. If your cut comes out uneven, file or grindit square. Losing a fraction of inch in length as compared to the plans of any part due to squaring it upwill not be a problem in this design.

Clean up any burrs from your cutting. These burrs are razor sharp and you will eventually getcut or scraped from these.


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Cutting a Keyway in the Drive Shaft:Your drive shaft should measure 14 with 3/16 keyway slot at each end. A keyway slot shouldmeasure approximately 1 long and 3/16 to 7/32 wide.Each pulley and drive wheel will have a 3/16 keyway. This is a slot approximately 1 long and 3/16deep. A key, slightly smaller than 3/16 fits in this slot. The function of this key to lock the drive shaft

and pulley together so the shaft doesnt just spin under load. To fit the pulley or drive wheel to theshaft, you will need an identical slot cut into your 5/8 cold rolled steel drive shaft rod. There areseveral ways to do this with out a milling machine and they are all a bit tedious and take a little time.

Keep in mind this keyway slot you are going to cut into the shaft does not have to be all thatprecise. The key will do the work. You just need to make the slot wide enough and deep enough forthe parts to all go together. This can be a 15 minute job or it can be a 2 hour ordeal depending on howconcerned you are about these things. Remember the slot is going to be covered with the pulley ordrive shaft.

One of the easiest ways to cut a slot is to scribe a 1 1/2 line along the axis of the shaft. Centerpunch several points along the scribed line and drill 3/16 holes approximately deep as closetogether as possible along the line. Using a Dremmel or other high speed rotary tool, remove the

residue metal web between the dilled holes. Dont worry if it isnt perfectly square or flat in thebottom. That doesnt really matter. Just hog out enough metal so the key fits in the slot and the pulleyor drive wheel will go on also. In developing these plans, this method was even faster than setting upand using a mini-mill. If you dont have a rotary tool, you will have to use a hand file and that is goingto take some time but it will still get the job done. Drill along a line just like before but drill a 2 lineto allow for the strokes needed by the hand file. File away until you have enough clearance in yourkeyway slot.

Some key way slots in pulleys are just a bit undersized making the key nearly impossible to fit.Simply file or grind down the key for a looser fit.

We have a fully machined drive shaft with keyway already cut available at:

www.USAknifemaker.com if you want to avoid cutting a keyway. These shafts are precisionmachined the entire length of the shaft. We source these from Beaumont Metal Works and these areused on the KMG grinder.


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Appendix E Abrasive Belt Basics

Open Coat vs. Closed Coat Abrasives

You will find abrasives listed as either open or closed coat. Open coat has less abrasive on the surface

to reduce clogging from materials. This is highly desirable in specific applications even though youmight think you will get more out of a closed coat abrasive. If open coast only has 50% to 70% surfacecoverage, Closed coat has more than 70% surface coverage is better suited for metal or glass. As ageneral rule, inexpensive belts, especially AO belts, are open coat.

BondingAbrasive belts use different types of bonding to hold the abrasive material to the backing belt. Somebonding materials are waterproof, some are not. The difference in technology between bonding agentsis as significant as the abrasive material.

Backing Material

Belt and sheet backing material varies in stiffness and water resistance. A J-Flex belt is very flexibleand is used in the slack belt attachment. The J-Flex belt will roll around contours. A Y or X weightbelt is heavy and stiff.

Friability

All abrasives wear and break down as they are being used. The measure of this trait is called Friabilityand is designed into abrasives. You want highly friable (easier to break down) abrasives in wood andother soft materials. When grinding metal, you want materials that dont wear and break down soquickly.

Grit size standards:To make things even more confusing, there are at least three standards for measuring grit size. Theyare the US based CAMI, Micron and FEPA. Most abrasives manufactured in the U.S. use the CAMIstandard. Engineered abrasives typically use the Micron basis which has a very small tolerance ofvariation to the grit size. Many abrasives also use FEPA as a standard. None of these standards matchup exactly. It is important that you know which standard abrasive you are using when you mix belttypes and brands.

Abrasive material:

AO or Alumina Oxide:Commonly found in wood working abrasives. It is usually on the very low

end of quality and price. AO belts wear out quickly when used for metal but are very appropriate forshaping and sanding handle material or even leather. Usually brown or sand in color and typicallyhighly friable which means it breaks up easily and exposes new sharp edges.

SC or Silicon Carbide:Usually black or gray in color. You will often find this in wet/dry sand papermarketed toward the automotive body repair market. Often used on metal or paint. It is more friablethan AO and wears very quickly. Most often consumed in sheet form. It is not commonly found inbelts.


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AZ or Alumina Zirconia:Typically referred to simply as Zirc belts. This is very hard stuff and isused in better or high quality belts. The downside to using belts with abrasive this hard is that youhave to use a fair amount of pressure to break the material down to expose fresh, sharp edges. Thisisnt usually a problem grinding knife blanks, especially with the harder super steels used in todays

knives. The low friability is a problem grinding or sanding wood or other natural material. Zirc orCeramic belts are recommended for knife grinding. They are more expensive but will out last severalAO belts.

Cork Belts:These belts have a thick surface of cork bonded to a belt backing. AO is embedded intothe cork to provide a grinding surface that has some give to it but will still grind or polish, dependingon the grit size.

Ceramic:A man made material just about as hard as diamonds in some cases. Ceramics are top of theline in metal grinding abrasives but most experienced knife grinders consider them worth the expense.Ceramic belts are more than just natural material glued to a belt. These abrasives are designed from

the bottom up for friability, uniform grain or grit size, cooler grinding temperatures and very long life.A ceramic belt will out last several AO belts and while they are often 3 or 4 times higher in price thanan AO belt, they will almost always out last those 3 or 4 belts and provide better performance. Thesebelts are as hard as they get abrasive wise but also have different levels of friability designed into themfor various applications. If you find ceramic belts dont stay sharp as long as you think they should,increase the pressure of your grinding application to break up the ceramic material and expose fresh,new sharp edges. A quality ceramic belt is usually the most expensive belt initially but ultimately thecheapest belt due to its long life and very consistent performance.

Engineered Abrasives: These premium belts are designed for specific applications. They have veryuniform abrasive material and can go to very small grit size. Norton Norax belts are an excellentquality belt using engineered abrasives that are as small as 5x microns or about 1200 SAE grit. Noraxare exceptionally good metal finishing belts but are nearly worthless on any other material as theyrelease dark gray abrasive dust that tends to stain anything other than metal.

Other types of Belts:Non-Woven:These belts are used to de-burr metal edges or to provide a uniform scratch pattern. Mostpeople are familiar with 3M brand Scotch Brite pads and essentially that is a non-woven abrasive.These are commonly used by knife makers to put a satin finish on knife blades. These belts are oftenfound in coarse, medium, fine and extra fine. The coarse belts will actually remove steel while thefiner grits tend to polish metal. These are for metal use only.

Leather Belts:These are just what you think they are. They are loop of leather in the form of a belt.They are used by some people as power leather strops after they have had some very fine abrasivecompound added to the surface.

Felt:These are belts made from the same material as felt. They are fairly thick at approximately thick. These almost always have buffing compound applied to them and are used for polishing metal.


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Grit Conversion Chart

U.S. Graded(CAMI) FEPA U.S. Graded(CAMI) FEPA

Microns DiameterGrit

Grit Diameter Microns Microns DiameterGrit

Grit Diameter Microns

0.3 0.0000118 36.0 0.0014032

P400 0.00137 35.0

0.5 0.0000197 40.0 0.001575 -

1.0 0.0000394 - P360 0.00158 40.5

2.0 0.0000787 44.0 0.0017228

3.0 0.000118 45.0 0.00177 P320 0.00180 46.2

4.0 0.000158 50.0 0.00197

5.0 0.000197 53.5 0.0020924

P280 0.00204 52.5

6.0 0.000236 55.0 0.00217

6.5 0.0002612

- 66.0 0.0025722

P220 0.00254 65.0

9.0 0.00035 78.0 0.0030418

P180 0.00304 78.0

9.2 0.000361

- 93.0 0.0036315

P150 0.00378 97.0

12.0 0.00047 116.0 0.0045212

P120 0.00495 127.0

12.2 0.000488

141.0 0.00551

P100 0.00608 156.0

15.0 0.00059 192.0 0.007498

P80 0.00768 197.0

16.0 0.000626

P1200 0.00060 15.3 268.0 0.010456

P60 0.01014 260.0

19.7 0.000775

P1000 0.00071 18.3 351.0 0.01395

P50 0.01271 326.0

20.0 0.00079 428.0 0.01694

P40 0.01601 412.0

23.6 0.000924

P800 0.00085 21.8 535.0 0.0208736

P36 0.02044 524.0

25.0 0.00098 638.0 0.024883

P30 0.02426 622.0

28.8 0.0011236

P600 0.00100 25.8 715.0 0.0278924

P24 0.02886 740.0

30.0 0.00118 905.0 0.035352

P20 0.03838 984.0

- P500 0.00118 30.2 1320.0 0.0514816

P16 0.05164 1324.0

1842.0 0.0717412

P12 0.06880 1764.0


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Appedix F Document history, errata and FAQ

September 9 Master materials list called for 2.25 of 2/sq by 3/8 pipe, it should have been 2.75Master list updated.

September 30 Front View Tool Rest drawings called for 6ea 4 straps, this should be 4ea.Drawing corrected.

September 30 Added comment to master materials list about tolerance of parts length. In short,nearly every part can be a little longer or shorter than the plans call for with no adverse affect.

September 30 Added this appendix to track any revisions or error corrections.

December 6 2007 removed errata notices, added alternate method for tracking block bracketconstruction, changed supplier web site to new domain (www.USAknifemaker.com)and to new emailcontact address ([email protected])

January 1/10/09 fixed a minor typo correction here and there. Added Pyrex supply source.

May 5/29/10 We have revised our motor recommendation to now include 3450RPM motor. We havedozens (hundreds?) of builders that have used this faster RPM motor with no problem. In fact on mylatest build I am switching to 3450RPM for the motor myself.Some minor editorial changes.Several typo's corrected.Added Wayne Coe as motor supplier in appendix and assembly manual.Added 1.75" tube can have 2" or 1.5" tube substituted. Locating 1.75" has been difficult for some.

MayWe have added plans for a Swivel Arm attachment. These plans are optional as are all the attachments.Some people find the Swivel Arm option as a very attractive alternative to tool arms.

April 4/14/12Reviewed for digital version release. Minor formatting changes.

9/4/12Final formatting for digital release.
http://www.midwestknifemakers.com/http://www.midwestknifemakers.com/http://www.midwestknifemakers.com/http://www.usaknifemaker.com/http://www.usaknifemaker.com/http://www.usaknifemaker.com/mailto:[email protected]:[email protected]:[email protected]:[email protected]://www.usaknifemaker.com/http://www.midwestknifemakers.com/


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