Newsletter of the Roleystone Men’s Community Shed Inc.

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EVENTS

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BIRTHDAYS

PROJECTS

Attendance December = 128 Average per session = 13

January 2019

BBQsOven HelpersTrinket Boxes

Chairman’s Notes:After a wonderful Christmas Ladies Night and our Shed sausage sizzle to mark the end of 2018, we look forward to change and progress in 2019.

Starting the New Year with the first change of our present arrangements, and after various conversations with Shed members, the Committee have decided that our present working hours of 9am to 12noon are not sufficiently long to provide enough time for projects and cleaning up. Consequently, starting with the re-opening of the Shed on Thursday 3rd January, the opening times will be 08:30am to 12:30pm. This will enable members to spend more time on Shed and their own projects, with the last 15 minutes being reserved for cleaning up. I hope this change in operating hours meets with everyone’s approval.

This year is the one in which we will have to build and occupy our new shed. Nothing less is acceptable, as our tenure at the present premises of the old school will be coming to an end at some point. I know we have had more than our fair share of setbacks, but this time we have to succeed. Be certain your Committee will do everything within their power to have us in a new home by the end of 2019.

If any members have ideas on future content for your newsletter, please contact me. All contributions welcome!

Looking forward to seeing you all in 2019.

PhilBrian

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January 2019Christmas Market Day

This year's Roleystone Christmas Market day was held a on a sunny and warm Sunday, 9 December. Once again it was very well attended with many visitors to our marquee. I'm pleased to report that sales were brisk with a variety of items sold, ready for those Christmas stockings!

It was also an auspicious day for the Roleystone Community Shed, who held their offical opening by the cutting of a ribbon. It was a shame neither of our Councillors could attend, but the Hon Alyssa Hayden was there to enjoy the event. Congratulations to Laurie and all those involved in achieving this milestone. We at the Shed understand all too deeply, just how difficult it is to get established in your own facility.

‘Ribbit’One of our late Treasure’s ambitions was to make a toilet roll holder shaped like a frog! Strange, you may say, but last year on a visit back to see relatives in Queensland, George came across a toilet roll holder shaped like a frog. Upon his return, he set about trying to recreate one at the Shed. Unfortunately he didn’t have time to complete his mission, so Neil stepped in and managed to complete one for him, shortly before George passed away.

Being the inveterate wood worker he is, Neil also set about producing six more frogs to satisfy the demand from George’s relatives. So he could reproduce them with accuracy, Neil made templates for each part of the construction process. George’s partner, Ronnie, will now be able to send them to Queensland in time for Christmas.

As a mark of admiration and respect for George, one of these frogs will hang over the wood working entry door in our new Shed, when we finally manage to achieve that goal. Thanks to Neil for all his hard work and perspiration.

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January 2019

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During the last Shed session of 2018 we not only had a plentiful morning tea, mince pies etc, but followed it by a sausage sizzle! Eighteen members attended, and I’m sure all would agree that the organiser and chef, David, did an excellent job. Not a lot of shed work done, but a very enjoyable prelude to Christmas Day. Don’t forget that we re-open on Thursday, 3rd January at the new time of 8:30am.

And to end with!

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Neil’s Woodworking Page

KNOW YOUR TOOL – G Clamp

To continue with the series on clamps, we shall explore the ‘G’ clamp, the most common form of clamping device. The ‘G’ (or sometimes ‘C’) clamp, is so named because of its shape.

It would appear from looking at early examples of this style of clamp, that the ‘C’ clamp may well have been the initial name, which then became the ‘G’ clamp, the design becoming more straight sided (rather than semi-circular) and had a distinct clamping plate.

It is most likely that the first type of clamp you acquired was a ‘G’ clamp, which was used to clamp wooden parts together for gluing, or steel for drilling or welding. However, you may have progressed to different types of clamps because the ‘G’ clamp is limited in it’s span, and large clamps are extremely heavy and expensive.

‘G’ clamps are typically made of forged steel or cast iron, though smaller clamps may be made of cast alloy.

To describe the clamp, the ‘G’ shaped frame has a flat clamping platform on the bottom leg of the G, while the top leg of the G is a threaded boss, through which a long, threaded screw protrudes. At the lower end of this screw thread there is a swivelling (usually ball) clamping flange, with a flat face. This is of similar size to the fixed clamping platform at the bottom of the frame. At the top end of the thread is a butterfly casting or a small metal ‘T’ bar, perpendicular to the

screw itself, which is used to gain leverage when tightening the clamp. When the clamp is completely closed, the flat end of the screw is in contact with the flat platform on the frame.

‘G’ clamps are rated by the distance between the bottom of the screw thread and the clamping platform, when the clamp is fully open. The size range for ‘G’ clamps is 2”, 3”, 4”, 6”, 8” and 12”. Some small hobby clamps of less than 2” are also available.The ‘G’ clamp has several distinct disadvantages, which are:• Weight. The 2”, 3” and 4” are not bad, but from there on they increase in weight to the point where a 12” clamp is a two handed job, just to carry it.• They require two hands to operate them, which is a disadvantage as you usually require one hand to hold the parts to be clamped in place, while the clamp is applied.• Cost. As the clamping range increases, the cost increases dramatically, along with the weight.• Lack of reach to clamping area. Typically a 4” clamp can only reach 2½” (frame to centre of thread).

Efforts have been made to make the ‘G’ clamp a single-handed tool, by the addition of a captive threaded wheel (in the frame) on the screw thread. The device works, but when operating a 6” clamp, you are juggling 1.8 kg in one hand, while attempting to turn the threaded wheel as well. I have included a close-up image of the device.

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Ion drive meets drone, as small plane flies with no moving parts

The Johnson Indoor Track at MIT probably won't go down in history in the same way as Kitty Hawk has, but it was the scene of a first in powered flight. A team of researchers has managed to build the first aircraft powered by an ionic wind, a propulsion system that requires no moving parts. While the flight took place using a small drone, the researchers' calculations suggest that the efficiency of the design would double simply by building a larger craft.

Ionic wind

In conventional aircraft, air is pushed around by moving parts, either propellers or the turbines within jet engines. But we've known for a while that it's also possible to use electrical fields to push air around.The challenge is that air is largely made of uncharged molecules that don't respond to electric fields. But at sufficiently high voltages, it's possible to ionize the nitrogen and oxygen that make up our atmosphere, just as lightning does all the time. The electrons that are liberated speed away, collide with other molecules, and ionize some of them as well. If this takes place in an electric field, all those ions will start moving to the appropriate electrode. In the process, they'll collide with neutral molecules and push them along. The resulting bulk movement of atmospheric molecules is called an ionic wind.

Calculations done decades ago, however, suggested that it wasn't possible to generate a practical amount of thrust using an ionic wind. Given advances in batteries, electronics, and materials, however, a team

from MIT decided the time may have come to revisit the issue.Doing so requires navigating a large series of trade-offs. For example, the lower the electric field strength of an ionic wind drive, the more thrust you get for a given power. Of course, if you drop the field strength enough, nothing will get ionised in the first place. Since the thrust per unit area is small, a more extensive thruster system makes sense—other than the fact that it will add to the drag and slow the craft down.

Still, after playing around with different thruster designs, the researchers found that it should be possible to generate sufficient thrust to get something airborne: "This level of performance suggested that steady-level flight of a fixed-wing unmanned aircraft might be feasible but at the limit of what is technologically possible using current materials and power electronics technology."

Finding a balance

The design they chose has a thin wire as its leading edge, where nitrogen and oxygen get ionised. Trailing behind that is a thin airfoil covered by the second electrode. This can both provide a little additional lift and allow the generation of an electric field that accelerates the ionised molecules from the wire to the foil.

But this design had to be integrated with the battery and electronics that make it work, as well as the wing and body that turned the whole thing into an aircraft. Some of those ingredients weren't even available until the team set to designing them.

"Weight constraints necessitated the design and construction of both a custom battery stack and a custom high-voltage power converter," the researchers write, "which stepped up the battery voltage to 40 kilovolts." To handle the aircraft's body, they fed a computer algorithm with a list of their constraints and had it optimise these to allow for stable flight with a limit on the potential wingspan.

The resulting hardware included a five-meter wing with a thin body containing the battery and electronics suspended below it before trailing off to a tail. On either side of the body, hanging off the

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wing, was a series of the wire/airfoil ionisers (two rows from front to back, both in a column of four for a total of eight). The whole thing weighed just under 2.5kg.

Given a bungee-cord-based launch catapult, the craft could fly about 10 meters when powered off. Fire up the ionic wind, and it could cover 60 meters and would frequently gain altitude while powered on. Measurements showed the thrusters collectively generated five newtons for each kilowatt of power, which is actually similar to the output of jet engines. But because of many inefficiencies in the system, the overall efficiency was only about 2.5 percent—well below that of conventional aircraft.

Still, the researchers have a huge list of potential improvements. The current design was limited by the decision to keep it flying inside the track at MIT. Allowing larger wings and a higher speed could get that efficiency up to five percent without any changes to the underlying technology. They also plan to explore things like different ways of generating ions, electrode designs that reduce drag and/or are integrated into the wing, and better power conversion electronics, all of which could boost things further.While the paper concludes with talk of silent urban drones and environmental monitoring craft that could stay aloft indefinitely, there's a chance that the technology will end up being little more than a curiosity. Still, given that it was enabled by developments that had nothing to do with flight, it'll be worth seeing what happens when people actually focus on developing this tech further.Nature, 2018

Do You Trust Your Bank?Robbers entered a bank in a small town. One of them shouted: "Don't move! The money belongs to the bank. Your lives belong to you.” Immediately all the people in the bank lay on the floor quietly and without panic.This is an example of how the correct wording of a sentence can make everyone change their view of the situation.

One woman lay on the floor in a provocative manner. The robber approached her saying, "Ma'am, this is a robbery not a rape. Please behave accordingly."

This is an example of how to behave professionally, and focus on the goal.

While running from the bank the youngest robber, who had a college degree, said to the oldest robber, who had barely finished elementary. "Hey, maybe we should count how much we stole?" The older man replied: "Don't be stupid. It's a lot of money, so let's wait for the news on TV to find out how much money was taken from the bank."

This is an example of how life experience is more important than a degree.

After the robbery, the manager of the bank said to his accountant: "Let's call the cops and tell them how much has been stolen". "Wait," said the accountant, "before we do that, let's add the $800,000 we took for ourselves a few months ago and just say that it was stolen as part of today's robbery".

This is an example of taking advantage of an opportunity.

The following day it was reported in the news that the bank was robbed of $3 million. The robbers then counted the money but they found only $1 million, so they started to grumble. "We risked our lives for $1 million, while the bank's management robbed $2 million without blinking. Maybe it's better to learn how to work the system, instead of being an armed robber." This is an example of how knowledge can be more useful than power.

Moral? Give a person a gun, and he can rob a bank. Give a person a bank, and he can rob everyone!

Bandiwords is the intellectual property of the Roleystone Men’s Community Shed along with its logos and banners. No other publication is associated with it in any form. Your contributions, comments & feedback are welcome. Please contact the author at: phil@aked.com.au or 0429 688 844