This coil box came on a car i bought recently. I think the coils box is about 1916 and came with this very nice set of soybean coils. They all have early style coil points, so i think the coils probably came new with the box. Ive heard that the coils were made of soybean, asbestos and a mix of the two?
(Message edited by adminchris on November 12, 2014)
Composition Soybean paste with an asbestos binder. This was referred to by Ford as the "cast case" coil
These are usually found in late 1916, 1917 and early 1918 Model T's. The Rip Van Winkle car was originally equipped with these coils.
They were discontinued when it was discovered the materiel used to cast the case was dimensional unstable. Most likely humidity related.
You commonly find them gnawed upon by Mice....hopefully the asbestos hastened their demise?.
I will call you to discuss these coils.
Although Henry Ford was a huge proponent of soy, I thought I learned from you that these coils were actually made from wheat gluten with asbestos as a binder, not soy.
My '17 originally had those coils. Dad took them out of the box for safe keeping and now they are lost. I am interested in purchasing a set if anyone has extras.
They are really neat. Those in the photo look to be in fairly good shape. I have one that I purchased from someone here on the board just to display, but it is not nearly as nice as these. Good find!
Yes "wheat gluten with asbestos binder"
Ron the Coilman
The coils Kim has have the Ford script on two sides. I have two with the Ford script on one side only.
I discovered a composite coil in a box of coils I bought off of Ebay. The coil had been emptied so I have only the shell.
The tooling to form these cases must have been interesting, as it appears a plug was used to form the inside, then the outer molds had to have had separate plates... much like a waffle Iron, to form the outer detail. The raw "paste" must have had the consistency of paper mache or bread dough before the "cooking " process, as the fiber content would not have allowed for much flow.
I am thinking of pulling some molds from this box to to see if I can make a few new cases from fiberglass, although a dough made from Bisquick and ground asbestos may be more period correct! Yummy!
Do they have a lid that can be opened like the wood coils? (=is it possible to change their capacitors?)
Roger, they do, there is a lip or "rabbit" formed in the case to mount the lid. How it was attached I do not know, but I find no adhesive other than the tar to hold it in place. Maybe Ron has better information on this.
All my years in this hobby, I have only ever had one of these coils. The outside body material apparently had shrunk with age. The tar inside applied outward pressure, and the casing split and twisted. The removable side had popped off and was lost.
Last year, when I was rebuilding a bunch of coils, I "restored" that one. The windings tested good. I chiseled out some tar and the old capacitor (replaced with a new modern approved one). Heated and clamped the case to near straight. Then J B Weld glued the cracks.
What I did for the missing side. This did not work really well? But I think with a bit of experimentation, it could work just fine. I used a little oil on the intact side of the coil as a parting substance. Made a small wooden form, then poured hot wax over the entire side of the coil. Part of the problem I had was, that I was concerned about the heat of the wax, and tried to pour the wax a little at a time. I also had trouble with about half the wax leaking out the edges of the wooden form. I wasn't happy with the wax mold I came up with. But I elected to continue with my experiment anyway.
I troweled J B Weld onto the wax mold and let it set.
I had some trouble separating the dried J B epoxy from the wax. Who would have thought? Epoxy is not supposed to stick to wax. But I got it apart. Cleaned up the new side piece. Surprise, surprise. It didn't come out too badly after all. When I was done fixing the coil, I trimmed the piece to fit and J B Welded it into the remaining original case. A spritz of flat black spray can and the silly thing doesn't look half bad.
Meanwhile, while the J B Weld was setting on the wax? I began my next level of experiment, which I never finished. I started making a mold from the side using silicon rubber (like out of a caulking gun tube). It separate from the side of the original case just fine (I am sure the remaining oil helped). It looks like this will work much better for forming a nice side piece. But I was short on time and used the other piece which looked fine rather than continue the experiment.
Now I just need to get the coil to a friend with a HCCT.
Drive carefully, and enjoy, W2