I was able to do some on-site checking of several RR supply foundries in 1986. In general they had major pattern cleanouts in the 50's. This does not mean that there aren't patterns out there, but it would take a lot of detective work to find them. I was surprised at the number of small foundries in Ohio, these are state of the art facilities and are quite able to produce the smaller stuff. There is also plasma arc deposition technology out there used to deposit iron on large castings to build them back to original thickness. There is nothing magic about any of this stuff, it's just a case of throwing enough money in the right direction.


lamontdc@adelphia.net

In making thermic-syphon patches for Pere Marquette 1225 we learned a little about the current state of patternmaking. There's a lot of fascinating capabilities out there. One system "slices" a CAD drawing of a casting into layers, and then uses a laser on a flat-bed plotter to cut the slices out of cardboard of appropriate thickness. These are then glued together to make a pattern usable for short runs of castings, as for prototypes or museum spares.

Our tool for making Nicholson thermic syphons was cast in steel in a small foundry in Michigan's thumb from a plastic pattern made in the experimental shop of one of Michigan's auto makers (which shall go nameless here because the pattern went out the door in a lunchbox late in the night shift, after the drawing came in on a disc. The same shop made similar patterns for model hulls for an America's Cup racing yacht, and crowed about it, but we were unable to interest the P.R. department in using a 2-8-4 firebox in their advertising.) This pattern was made untouched by human hands, from a CAD drawing of the space inside the syphon, by redrawing the old Nicholson blueprints supplied to Lima Locomotive Works for the Berkshires. As noted above, the laborious part is making the CAD drawing - the patterns are made automatically.

Aarne Frobom
The Steam Railroading Institute
P. O. Box 665
Owosso, MI 48867-0665

froboma@mdot.state.mi.us

Some 6 years ago, I got a job doing welding for a wellknown locomotive builder here, outside in a 40 foot scrap bin were 100's of wooden patterns.
Most dated from the 50's for items like;Radiator header tanks, Bogies,Brackets, Transoms, etc. After work each day I loaded patterns into my van and trailor. The biggest would have been about 800lbs weight and 6 foot long, no body helped at the time, but they were happy to stand and laugh at me.The price I was told was to be one dollar, thinking that it was one dollar each I realised I had a bargain.However they charged one dollar for all the firewood each day I took. Many more patterns were lost to landfill before I got there, but at least I saved about 5 to 6 tons of them. No steam stuff in this lot. Lesson is, take everthing you see now, tommorrow will be too late.
Happy hunting. regards jeff.



dalyw@bigpond.com.au