Rotor Winding Tooling

t-Butyl Perbenzoate (another name it goes by is t-Butyl Peroxybenzoate) is usually stored refridgerated because it contains a temperature sensitive peroxide group. One use of this is to cure unsaturated polyesters resins (UPR) i.e. the type of resins used in fibre glass applications. Can also be used to polymerize acrylic monomers to make acrylic resins. When heated the peroxide group is cleaved to form free radicals which then initiates the free radical polymerisation of unsaturated materials like the fibre glass resins. By itself this chemical will have not much value for use on stators, will be used inconjunction with an unsaturated resin. 15 years now since I worked for the big European UPR manufactures including TOTAL, Cray Valley, CCP(USA) and Arkema.
 
WOW!!! Add Chemical Engineers to the list of technical wizards :bow::bow2: on this forum! What's next? Rocket scientists? Wait, isn't there an aerospace engineer on here too? Just goes to show you the diversity and wealth of knowledge we have here. I'm humbled, standing in the shadows of such intellectual giants! :umm:
Seriously.
 
If I may be allowed to digress a moment, I bought that very expensive neodymium ring magnet off of Amazon and put it in my Ricks replacement rotor. As you can see, the resultant magnetic force was very strong.



Unfortunately, when I put the second half of the rotor on, all the magnetic field disappears, and I just have a paperweight. I assume I am just creating a rather intricate magnet keeper once it is all together. Does anyone have an idea as to how I could rectify this? If I could get this to work, it would be the beginning of a cheap home brew PMA using the stock rotor, slip ring plate and trigger magnet.

EDIT: Honestly, this is by far the worst forum I have ever used for attaching photos..
 

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Image inserted. Many times as it turned out, had to cull about 8 identical images.

The biggest worry here is the low Curie temperature of the neo magnet, 80C, or about 180F. I would think some ventilation ports would be advisable.

The ID of the magnet is a bit big, so it would need a collar to center it, and it is much thinner than the gap between the rotor halves, so a cushion disc of some sort would be required to keep it equidistant between both rotor faces. This sucker has some pull, believe me! I had to put two sockets behind the magnet edge between opposite claw gaps and close up the vise to push it out of the rotor cage. I want to keep installations to a minimum due to the brittle nature of the magnet. It wants to mate up with the iron rotor RIGHT NOW!
 
MacMcMacmac, I have been giving your ring magnet some thought??? I believe the answer is the rotor is functioning as a handy carrying container. The ring magnet already has its own core and the field is confined to it. When you have a coil in place the current induces a magnetic field in the rotor body which functions as the iron core. You could imagine unfolding the rotor to give a cylindrical core with pointy bits at each. If you want to magnetize this bar you could cut it in two and insert a strong circular magnet. This circular magnet would be the same diameter as the inside rotor diameter i.e. the diameter of the hole in the middle of your current ring magnet.

I have seen in the past where people add permanent magnets to a rotor, they drill and insert their magnets into those outer triangular faces. This way when the rotor is spinning the magnets' faces are whipping past the iron cores of the stator windings. The magnets would be in the alternating sequence NSNSNS.... around the outside faces. Adding these magnets is effectively the same as inserting a big round magnet in the center of the rotor's iron core as mentioned earlier. In fact if you imagine folding the rotor's iron core you would have a cylindrical bar with pointy bits at each end, at one end would be all the North magnet faces pointing out and at the other end all the South magnet faces pointing out.

It is easier to just press the rotor halves together and drill each triangular face and insert a couple of magnets in each, would be difficult/impossible to insert 1 large magnet in the core and be able to press the halves together then thread it all on to the crankshaft.

That's my thinking done for today.
 
Guess I should update this thread for those of you not following my restoration. The rotor's installed and looks to work normally. It's putting out 14.1V at about 2500-3000 rpm. Now it just becomes a question of longevity....

 
Low 14's might be the average or best these later Specials do what with all the rear light bulbs that come on with the key. Earlier models had just one bulb back there, these have 4 (2 tail, 2 license plate). Temporarily pull those 4 bulbs and re-test, and you might see a few tenths of a volt higher output.
 
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