April 2018

Bluewater Bulletin

Bluewater Model Engineering Society Sarnia, Ontario

Vol. 33 No.6 March 2018 Editor John Lovegrove

Our next meeting will be on

April 9th, 2018 @ 7:30 pm

Northern Collegiate Room 128, Indian Road, Sarnia.

The March Meeting

Again, with the weather cooperating, attendance at the meeting was good. Our Treasurer gave his report and all is still well with our finances

Bruce Mannerow gave an update on his hinge making device. Basically, this is a block of steel with a slot ending in a circular section that you push a piece of metal strip into and it curls the end around to form the pivot part of the hinge. With the right thickness of metal, it works well but if the material is too thick it does not work well at all.

He talked about NAMES this year. It will be on the 21st and 22nd of April and several of us who have attended most years previously plan to go again. We will have another meeting before the show so we can finalize who wants to go and decide on car pooling arrangements etc.

Bruce went on to discuss what is available on Internet Archives. Apparently the 30th edition of Machinery’s Handbook can be downloaded from that site. I have used this resource myself to download old engine books and it is amazing what is available. It is all stuff where the copyright has expired so it can be made freely available. I have found that searching the site is not always too easy.

It is also possible to do patent searches on-line; US patents are really quite easy to find. There is also a way of searching out European patents, including British patents going back to the 1890s.

Bruce also talked about motorcycle mechanic and dare devil racer Guy Martin who has a number of entries in the Guinness Book of Records. He has recently constructed a replica of a Mk IV WWI tank. Just Google "Guy Martin Mk IV Tank" and a number of items come up. Apparently, he wanted to drive the 30-ton machine through Lincoln City Centre on Remembrance Day but this was kiboshed by the local police. (Fosters built the WWI British tanks in Lincoln.)

There is quite a lot of interest in the club in wagon type wheels. Bruce’s artillery pieces have them and Kasey has made a few of them over the years.

If you work it the other way by turning the rotor, the alternating magnetic field through the coils generates electricity and you get 2 outputs (900 out of phase) from the 2 sets of coils.

You then connect these outputs to bridge rectifiers and capacitors so as to get a reasonably smooth DC output.

Kasey is using LED lights so the power draw is not very great. The power house has a workbench and tools for maintenance work and a stove to keep the operator warm in the winter. (It was

Check out Dave and Diane Engel’s website in Montana: https://engelscoachshop.com

There was some discussion about the Hulett (ore) Unloader that Don Eastman has modelled (see last month’s newsletter.) Don passed around a collection of photographs of the model for us to look at. Some of us had looked at the YouTube video that has been made of the unloaders in use. They must have been quite impressive.

Another subject brought up by Bruce was the use of tumbler systems for cleaning up and polishing parts. No one seemed to have any direct experience but if you Google "Vibratory Tumbler" a lot of advertisements come up for them, even Canadian Tire offer one. There is mention of them being used to clean up nuts and bolts, even coins. One question was what (abrasive?) medium is used. It looks as if special resin chips incorporating aluminum oxide are offered as one option.

Ed Spencer talked about "cast iron colds." He came down with a cold after machining some of this material and believes there was a connection. Other people talked about the dust created when machining cast iron (which is normally done dry) and that care should be taken to avoid inhaling any. (Using some liquid coolant to keep down the dust may be worthwhile although it is not really required from the machining perspective.) Whatever you do it always seems to be a messy operation.

Show and Tell

Kasey Schuilenberg had the largest (but not the heaviest) item; a steam power house. He was given the steam engine by Dirk Henkemans but as received it was not working. After a little TLC he got it running and it now seems to work quite well. The generator was made from a stepper motor out of an old fax machine. Stepper motors have what amount to a multi poled magnetic rotor and two sets of coils in the stator. If you energise one set of coils the magnetic poles align with the poles corresponding to those coils. Then, when you energise the other set of coils the rotor moves around one step to align with this next set.

largest (and heaviest) model anyone in the club is building.

Brian Lawson had another of his "what the heck is it" items. It looked a bit like a holder for a very large (~1½") boring bar but it had a groove running along one side. No one had any idea of what the item really was.

hard to get a photograph that really shows the inside adequately.)

Nick Jonkman has been making good progress on his model of an 1830 McCormick reaper.

The cutter bar is now complete along with a lot of the wooden framework. Apparently, those curved pieces of wood presented a significant challenge.

Tony Koolen has been doing some more work on the tender for his Case traction engine. It looks as if this part (at least) is nearing completion. This is by far the

assembled the bottom half of my Sealion to check that everything works OK. I put together a mounting system to go in my old lathe to turn everything over at a reasonable speed.

I have found in the past that if everything is built to reasonably close fits, the friction initially is quite high. (You can easily lose more power this way than the engine actually develops.) With the pistons, connecting rods and crankshaft all assembled and the oil pump operating, the engine has been run in the lathe for several hours. It is now much freer than it was when first assembled. I made the coupling piece from round wood so that if anything seizes, the wood will split apart at the couplings, avoiding further damage.

When I eventually get the engine finished (?) the mounting will serve as a temporary base for the test runs.

In this engine I have made use of quite a few O rings to form static seals. They are used extensively in industrial applications, particularly in pneumatics and hydraulics and are very good for sealing flanges etc. where pressures and temperatures are moderate. So long as the housings are correctly machined a leak tight joint is produced that can be taken apart and re-assembled without renewing the seal.

There is one watch-out that I think I have mentioned before: "Standard" O rings have a cross section slightly greater than the nominal. For instance, a 1/16" nominal section O ring has an actual cross section diameter of 0.07". However, the Chinese made rings you typically find at Princess Auto and Harbor Freight have an actual cross section which is the same as the nominal. If you are starting from scratch and size the housing appropriately, this is not a problem. However, if replacing an existing O ring, you have to be more careful.

Housing dimensions for standard O rings are readily available and for my own purposes I have adapted these to give sufficient "crush" on smaller section Chinese O rings. I can share the tables I have generated with anyone who is interested.

Bruce brought along the latest parts he has made for his 4 ½" Howitzer.

These are the items that act as brakes on the wheels. His hinge making device was made to produce the pivot parts at the right-hand end of each brake arm. (As they appear in the photograph.)

With the oil pump together with inlet manifold, outlet manifold and oil pressure relief valve complete I have

Since there is some space left on the page I will put in a couple of photographs of Guy Martin’s tank.

Meetings for the rest of the Season

2018

April 9th