Model electric motor

[petek]

I have a battery operated model electric motor from my youth c.1960's. It's an SEL ref: 3/1262. From t'internet searches I understand SEL were part of Mamod, the famous model steam engine manufacturers.

It used to give me lots of fun when "I were no'but a lad" and helped me to understand how electric motors worked. Recently my grandson came across it in the back of a cupboard, and I want to show him how it works but one of t he copper contact strips which rub on the commutator is broken and bent so I want to make a new one.

I need a small piece of flat copper, approx 0.1mm thick from which I can cu t out a shape approx 7mm x 22mm. Don't know where I could buy such a small piece (I've looked at Hobby's Ltd catalogue but no joy) or what other appli ance/machine I could cannibalise.

Any ideas Thanks Pete

[Jim K]

's an SEL ref: 3/1262. From t'internet searches I understand SEL were part of Mamod, the famous model steam engine manufacturers.

o understand how electric motors worked. Recently my grandson came across i t in the back of a cupboard, and I want to show him how it works but one of the copper contact strips which rub on the commutator is broken and bent s o I want to make a new one.

cut out a shape approx 7mm x 22mm. Don't know where I could buy such a smal l piece (I've looked at Hobby's Ltd catalogue but no joy) or what other app liance/machine I could cannibalise.

torch innards?

Jim K

[F Murtz]

Copper pipe cut and flattened.

[Graham.]

I'm not sure why the brushes would need to to copper. Tinplate cut steel drinks can?

[harryagain]

It used to give me lots of fun when "I were no'but a lad" and helped me to understand how electric motors worked. Recently my grandson came across it in the back of a cupboard, and I want to show him how it works but one of the copper contact strips which rub on the commutator is broken and bent so I want to make a new one.

I need a small piece of flat copper, approx 0.1mm thick from which I can cut out a shape approx 7mm x 22mm. Don't know where I could buy such a small piece (I've looked at Hobby's Ltd catalogue but no joy) or what other appliance/machine I could cannibalise.

Cut up some copper water pipe.

[Nightjar]

I suspect that you want phosphor bronze. That is springy and will hold itself against the commutator far better than copper. I used to buy it cut to width from Smiths Metal Centres, but in rather larger amounts than you need.

Colin Bignell

[Jim K]

0.1mm thick!?

Jim K

[The Other Mike]

No he's far thicker

[John Williamson]

+1

Copper brushes on a copper commutator are not a good idea.

Google say this lot:-

Sell phosphor bronze shim, but you may fall foul of a minimum order value.

Depending on the size, Triang X04 (Or other similar) motor brushes are made of phosphor bronze with a copper-carbon block bonded to the end, and may give better performance.

[Ian Jackson]

I've got some old phosphor-bronze draught-proofing strip that I took off one of my doors. It's about 1" wide, flexible and springy, and I think it's ideal for what you want. If you want, I can chop a bit off and pop it in the post. [I just knew it would come in useful one day.]

[The Natural Philosopher]

Peted, I have any amount of electric motors for models lying around doing sod all.

if yu can tell me what te dimesnions of it are, if possible [ost a picture, and what batteryu voltage it is suppsed to run on, I'll put something in the post to you.

Ive probably got a scrap one with good brushses but blown bearings anyway.

see if it resembles any of these

[newshound]

+1. eBay for Phosphor Bronze Strip. This is more than you want

but I suspect you will find something suitable especially if you try some of the shops.

[John Williamson]

I'd say it's one of these:-

[The Natural Philosopher]

Oh? sweet! a real 'educational' motor then..

yerss..might have something that would repair that..i'll have a look

this is a 'speed 400' end bell with two phosphor springs that actually have proper carbon brushes on them.

about 20mm diameter

yours if its any use.

[Dave Liquorice]

Damn good stuff, inherited a roll of it from my father, who may have inherited from my grandfather...

Yep I agree springy and thin (cut and hammered copper pipe, WTF!).

I was goig to offer as well but I don't know where it is ... I know I haven't slung it out, far too useful.

[Ian Jackson]

Of course, a similar product is available in plastic - but I doubt if would work very well in this application!

I know exactly where mine is (I went out and checked that it was where I thought it was - in the garden shed). If the OP wants a bit, just email to my corrected address.

[F Murtz]

Seems to be an echo in here.

[F Murtz]

Copper is malleable,a hammer will fix it.

[F Murtz]

He was just asking for a source not advisability.

[harryagain]

They aren't but I remember a motor I had back in the sixties with this arrangement. They were crap. He'd be better to get a modern one, far more power and longer lasting.

Or get one out of a car, windscreen wiper, window lift or wing mirror for tiny ones