MTFCA Forum

Because it worked and was painted, I always assumed that the mag ring in my 1915 runabout had been rebuilt.

But recently it fell on the floor and suffered this boo-boo, revealing that under the paint was brittle old insulation. Maybe I could patch it up and use it and it would be fine, but I'm not delighted with the idea of relying on that 105-year-old insulation. With Total Re-coil gone, is there a go-to source for a fresh ring?

I was thinking that the business was taken over. I’m thinking I read that on the forum but not sure.

R V Anderson did mine. At the time there was a $20 core charge and he told me I could either send him my core, which would cost about $25 or pay the core charge. I didn't have to think about it too long.
Ralph

Bill Lucius is the gu6 around here. Supplies a whole bunch of them. I’ll share his email if anyone drops me a line tmorsher@icloud.com

I got mine from RV Anderson. it was cheaper to pay the core charge than to pay shipping to send a core to him. He had one all ready to go, so i didn't
have to wait.

Steve,
there is a guy here in Denmark that make them, but.....

I’d never put any old field coil in that was coated with anything.

You know how clean you have to prepare a surface when you do body work? It’s impossible to get a used field coil that clean...

I rewound 3 coil rings following the instructions in the book, "electrical system". I installed 2 of them in 2 of my cars and the work very well. The third one was donated to the club and auctioned off. I don't remember who bought it, but haven't heard any complaints.
Norm

Thirty to sixty years ago, that is what passed for "rebuilt". All they did was soak most (never gets all) the dirt and oil out, or some people burned the outer insulation off (hoping the inner insulation wouldn't be badly damaged!), then coated with the "red stuff". In actuality, it usually worked okay. Burning provided a better surface for the red stuff to stick to, but if not carefully done could do enough damage to the inner layers of insulation to result in failure fairly soon after installing (they could be tested to know they worked okay after being "finished" but no test could guarantee against soon future failure). Soaking the oil and crud out was less likely to result in insulation problems after coating, however, it often resulted in bits and chunks of the red stuff and old insulation falling off and getting thrown around the inside of the motor (often resulting in abrasive dirt in the oil in bad places).
Generally speaking, not a highly recommendable method. All new winding and insulation properly coated with modern thermal and oil resistant coatings is much better.

R V Anderson did mine. Very well done. But I will suggest to send your Mag instead because that wil save you time to put it back with the same shime and adjustment. You will save alot time of adjustment. My 2 cents.

Steve,

I could do your coil ring but it will be too expensive to send it to Belgium and back to you,I think.

Andre
Belgium

Steve, I have one rewound, surface ground, double oval stack on hand ready to go. Email me at rvmodeltATnetsyncDOTnet

No time to be cheap as a stem winder needs a hot mag!! Bud.

All the supplies you need to do your own field coil probably will cost about what RV sells one for.

If you really want to do your own, I would suggest using a single stack coil. It’s about half the work & supplies. Your ‘15 should have 3/4” magnets and if so, a single stack coil will work fine.

Steve,
I will try to answer your questions.

1 From what I've read of Kapton™ tape it appears to be an ideal insulator to wind in the coils. Has anybody here used it, and if not what have you used?
Kapton Tape will work good but is hard to find here. I take M3 masking tape that resist detegent and oil. After having cleand and straighten the cupper wire I fix them on a straight piece of wood that takes all the lenght of the string.Set the insulating tape on one side of the string.
You will need to make 32 strings to make 32 coils .

2 On a double-coil ring I expect there should be insulation between the upper and lower coils. Correct?
Each double -coil is made out of two coils attached together in a way that the direction of the windings are the same. The two coils of each double coil need to be insulated very well from each other. I use gasket paper to do this.

3 One suggestion I read was to anneal the copper before unwinding by putting the ring in an unspecified "heater" or perhaps on a charcoal grill. Any comments on this?
I never done this but it is maybe an easy way to get the grease and dirt off. I clean mine with disolvent and elbow grease. At the same time I straigh them up.

4 What should be wrapped around the coils?
3/8 cotton tape 130cm is needed for each coil.

5 Should the strips between coils be wrapped, or is the final overall coating sufficient?
The final coating will do the job just put a lot of it on them to fill up the place where the string come out of the coil.

6 What is the best coating?
I use polyester coating It is done in 4 layers. First a primer to give the polyester coating a better fix to the cotton and steel, Two coats of polyester resin, to finish I use clear coat.

I will try to set a few photos on the forum. It will take a few threads.

Good luck
Andre
Belgium

next photos.

And a few more.

just forgot to tell.
Price for all the needs is less than $20,-
Time spend is about 20 hours. That makes the price for a rebuild one.
A single stack will take me about 10 hours to rebuild.

Andre
Belgium

All the supplies you need to do your own field coil probably will cost about what RV sells one for.

With shipping that's over $300. Which supplies are expensive enough to make the cost that high? I figured that most of the cost was in labor.

Bill Lucius is not set up for the double stacks, they can do them but prefer not to. If you do your own be careful on soldiering the doubles together so you do not pull a short. All the supplies are easily found and most of the time is in the labor.

A quick easy way to clean the copper is Drano, let it set in a bucket over night then scotch brite the copper and good to go.

The last coil ring I did was a double round with demontable cores for a 1912 engine.
As you said Steve the most of the price is set by labor.
For the double round coil I asked €240.- about $260.-.
The raison why I started to rebuild magneto coil rings was first the price but also the shipping price. To belgium it is easy $80.- that twice. I need to send the core before they send me a rebuild one.
The price I am asking do not cover my labor but I only work for friends so... .

André
Belgium

Mine had that problem too, but on more places than yours (and because of the problems that led to me taking the damned thing out, I had to fix it too), I just mixed up some potting epoxy and applied liberal coats to the exposed coils. Then then painted them with that spray-on red electric varnish you get from vendors like Lang's.

Works pretty good, haven't had any problems so far.

Here's a jig I made to wind the coils. I have more pictures and info. I got some of my supplies from the local electric motor rewinding facility who also varnished and baked the finnished ring. I made the handle for this jig out of a long 1/2 inch bolt.

Here bellow the one RV Anderson made for me in April this year. I'm very please with his job.

Steve: I've done one single stack, probably won't do another, the vendors do it better and faster.

I would never roast or cook a core to clean it, too much risk of warping the frame. The original shellac was a bigger challenge than the oil, I washed off most of the oil with kerosene, let it dry and then soaked in denatured alcohol softening the shellac until I could remove the coils without damaging them, since I re-used the copper. (I think all rewound single stack are done these days with new copper strip, I think double stack still re-use the copper) Various solvents, scotch pads and even course steel wool worked for me to clean up the strips. I made sure there were no dings in the strip that might work thru the insulation. Before I rewound the copper I stretched each strip about 4" (~4" in 12' = ~3% strain) which made it straight and flat.

I used McM-Carr p/n 7574A11 fiberglass tape for the between layers and overwrap insulation. That tape silicone insulation is rated up to 500F and is 0.007" thick, comparable to original paper insulation thickness. I split the 1/2" wide tape for application to the strip and used full 1/2" for overwrap. The original Ford overwrap was cotton twill according to one source I talked to.

For the insulating washers between the coil and frame I used 0.020" thick fishpaper, available in sheets from McM, thinner might work better for between coil insulators on double stack.

For final topcoat insulation, clear Glyptal 1202 electrical varnish. I first 'glued' the fishpaper discs and individual coils to the ring with the 1202, waited a day, made and verified the electrical connections and then saturated the entire assembly with liberal brush coat of the varnish. (Apply liberally, don't just give a hairspray coating from a spray can like some videos show). Let it cure a day or two and then bake at 200F for an hour to finish cure. The 200F and one hour bake is from the Glyptal manufacturer, and there is very little smell from the oven.

Andre shows how it all goes together and his work is excellent. RV has excellent products, and very fair prices.

Have fun, jb

Steve,
I just send you a PM.

Andre
Belgium

Steve, Adam D. is entirely correct; if you're looking to save some $$$ then install a rewound single stack. Any of the flywheels with 3/4" magnets will work with one. I have one in my '14, along with a starter flywheel, so, if it ain't unregular and irrelijious to seggest it (apologies to Mark Twain) I could install a starter without having to pull the engine.