DC motor rewind help ?

[Andrew B]

Seems like Catch 22 , I need to unpick the top couple of windings to learn/discover the winding pattern regarding the connections to the commutator. I have already figured out that each winding covers 7 slots, i have discovered the end/beginning tails but with the whole thing stuck together, I can't get a winding off.

The "auction" site sellers mentioned are mentioning their product containing DCM with cautions are merely using such cautions to "big up" their product (and the price)

[Andrew B]

From a Newnes technical book on "Rewinding small motors"

Rewinding Small Motors describes the technique of rewinding various types of motors, such as split phase, capacitor-start, repulsion, repulsion-induction, repulsion-start, shaded pole, three-phase induction, universal, and d.c. The book describes in detail the rewinding process. The technician should start by determining the following: (1) coil connection; (2) number of turns per coil; (3) number of coils per pole; (4) the gauge of the wire; and (5) the space occupied by the winding. The book notes the importance of the varieties of wind and the various techniques adopted to obtain the optimum wind for any particular type of armature. Varnishing and finishing forms part of the whole operation; this adds insulation between turns, secures the whole winding against the action of centrifugal force, and also seals the part from moisture or dust. A motor-driven winding machine should have speed control, a lead-screw reverser, and a wire guide. The book points out that a coil cannot be wound anyhow as the coil voltage governs the technique of winding that is to be used. The book is suitable for fitters, engineers, apprentices, technicians, and students of mechanical or electrical engineering.

[Andrew B]

I found a bottle of stripper / remover in a dark corner of the garage where the BIG spider lives, lets see if this stuff does the trick

[merlinmaxwell]

Or pop it in the oven at 150C for a day or so...

[crackle]

Originally Posted by merlinmaxwell

Or pop it in the oven at 150C for a day or so...

It might make the roast chicken for Sunday lunch taste funny with the smell of burnt enamel.

Mike

[merlinmaxwell]

OK put it in a tin first, I was serious about heating it up for a few hours to degrade the enamel.

[Andrew B]

I tried that at 190, it softened the epoxy which I was able to pick off easily, the cheapo paint stripper finished off the cardboard covering the armature slots, now I am left with the wire enamel stuck together, yesterday I gave it a good brushing with the methylene dichloride stripper and have wrapped the assembly in clingfilm for a couple of day.

[emeritus]

E.M.A. Model Supplies sell dichloromethane for use as plastic solvent: £6 for a 500ml can, also available in 57ml glass bottles.

https://www.ema-models.co.uk/index.p...ent-500ml.html