Sept. 2014
Bluewater Bulletin
Bluewater Model Engineering Society Sarnia, Ontario
Vol. 30 No.1 October 2014 Editor John Lovegrove
Our next Meeting will be on
Monday, November 10th, 2014 @ 7:30 pm
Northern Collegiate Machine Shop (Rm. 148), Indian Road, Sarnia.
The October Meeting
Neil Blackstock stated that this would be his last meeting as president and that an election for a new president would have to take place.
Before this happened a few other items were discussed: Our Treasurer was present, he gave his report on our finances and indicated that he would be willing to continue in the position. He also collected "subs" for the year. Our Secretary was not present to indicate whether he would be willing to continue.
Bruce Mannerow had a few show and tell items: He had parts from an old torch to give away, it was originally sold by Radio Shack. The second item was a block of camphor that when placed in a tool box helps to keep items from going rusty. These are readily available from drug stores (they probably keep the moths out of the tool box as well.) The other item he had was a simple magnetizer/demagnetizer that works without an electrical supply. Bruce also talked about Gerald Wingrove in the UK who has been awarded the MBE for his services to model engineering. Apparently he has made some really fantastic models and in his retirement he is starting on the sailing ship from 1878 the "Falls of Clyde." This has a riveted steel hull. . http://www.wworkshop.net/Other_Models/Gallery-4.html
Alan Olsen talked about something that Dave Finley (a former club member) is making: It is a model of "Excalibore;" the machine used to bore the new rail tunnel under the St Clair River.
There was some discussion about activities at Komoka. Ed Spencer gave a brief review and apparently had a busy summer running on the track. He has also modified the stainless steel firebox liner in Sweat Pea which has resulted in much improved steaming.
Tony Koolen had been there both with his electric locomotive and Dirk’s old steam locomotive. Tony also mentioned that his brother from Port Franks will be putting on a seminar on casting items in 2 part resin (more later.)
Stu Brownlow talked about the laparoscopic prostate surgery he had had. He was very impressed with the equipment they have in London, some of which has been bought using money raised from donations. He talked about the incidence of prostate cancer in men within the age group of our club members. Stu is now involved in the money raising efforts and asked if the club would consider donating $100. The donation was approved on a motion by Nick Jonkman/Alan Olsen.
Returning to the appointment of a new president; the clear favourite Bruce Mannerow was elected in a landslide victory. Talking to him more recently he has been busy preparing for the coming year. Apparently he has spoken to Peter Esser who does not wish to continue as secretary so we need a volunteer for that position. (Bruce has also warned that anyone not at the next meeting could be appointed in their absence!!)
Neil handed over the attendance book and gavel to Bruce ready for the next meeting (and Presidency.)
Show and Tell
Tony Koolen brought some wheels that have been cast in resin (mentioned earlier.)
He also had the reversing lever and throttle lever he has made for his Case traction engine. (He seems to be one of the few people able to get anything done during the summer.)
On the de-magnetizer theme; Kasey Schuilenberg brought along his heavy duty mains powered device.
Our visitor Martin Beales brought along his Odds’n Ends Hit’n miss engine.
This is a Philip Duclos design and is fabricated mainly from pieces of steel plate (hence the name.) Apparently it uses a Viton "O" ring instead of a conventional piston ring. I was always sceptical about using this method of sealing in an internal combustion engine because of the high temperatures, but apparently it seems to be OK. (Someone had a Wyvern engine at the last Cabin Fever Exhibition with this arrangement.)
Using Resin (Polymeric) Materials in Model Engineering
Tony’s mention of his brother’s work with casting resins set me thinking about using them in our hobby. I have spent most of my working life in the area of plastics and rubber and so I have some background on the subject. Tony handed out a leaflet on the materials his brother is using and I followed up by finding some more information on the web. Here is the link:
http://www.smooth-on.com/Urethane-Plastic-a/c5_1120_1209/index.html
"Plastics" came into widespread use mainly because of their ease of forming into almost any shape imaginable. Thermoplastics are heated up to soften them and either extruded or injection moulded. They then harden on cooling. Other materials come in their (liquid) monomeric form and when mixed with a hardener, polymerize to form the solid polymer. If they are sufficiently fluid to start with they can be moulded, as is the case with the materials Tony’s brother is using. Epoxy resins are in the same category and come in a variety of viscosities depending on the intended use.
As a mechanical engineer my main interest is in the mechanical properties of a material and whether it is OK for the intended use. The other issue of course is resistance to whatever the material is exposed to: Polymers do not rust or corrode like metals but they can be affected by oils, solvents and other chemicals. Also, many polymers are affected by exposure to the UV in sunlight. Another "watch out" is that most polymers lose their strength rapidly as temperatures rise.
I started to put together a table giving typical tensile strengths and moduli of various materials for comparison purposes but published data is very variable and I have run out time. However, according to the literature, the "Smooth Cast" resins have a tensile strength of ~ 3000 psi which is only about a 1/10 that of mild steel and some aluminum alloys. Other plastics are similar. I will try to get some better data assembled ready for the next newsletter.