21 replies to this topic

[Mad Mark]

Finally got a zapper. I read a bit already. Cheater has good info on his motor blueprinting thread. Just wondering if I can zap a bare can with just magnets and don't need a slug inside? And if I need a slug can I just use a crappy old arm or something?

Can I zap a whole motor if I just remove the brushes?

This is all for D size motors and assorted vintage stuff not worried about modern stuff. Not trying to get best results just as long as i'ts better than almost no brakes on some of my motors.

 

Any help is appreciated.

[Dave_12]

You need a steel slug and it needs to be a good fit.

[Mad Mark]

Thanks! Does a bolt or similar random piece of metal work?

[Bill Seitz]

The slugs I've seen looked like they were cut from steel or wrought iron rod of an appropriate diameter, but because no standard rod is exactly the right diameter, I'd guess they'd need to be machined to size. The idea is to provide an efficient path for the magnetic field between the magnets, air not being a great medium for magnetic field, in order to achieve maximum results. In that case, something smooth and a snug fit to minimize air in the path will work best. Iron is actually a better conductor of magnetic field than steel, so iron slugs would be ideal.

 

It doesn't seem as though maximum efficiency of the zapping is of utmost importance to you. In that case, you could try just using an old arm, bolt, or any piece of steel/iron of approximate dimension and see how that does. You're not going do anything irreversibly damaging in trying, and that might be good enough for you.

 

There's no reason zapping a whole motor can't be done, but remove brushes. Again, for what I think you're looking for, try and see.

[Wink Hackman]

A close-fitting mild steel slug is ideal, but if you can't turn something to fit you might try using a bolt (not stainless). 1/2" will be a bit small, 9/16" is just over .560" so it might just fit in a D-can with big airgap. Or try 13mm and 14mm to see what fits best, you need minimum airgap. Maybe better to use an armature - zap once, rotate the arm 180 degrees and zap again.

 

Oh, and be aware that the zapper should be able to completely invert the polarity of the magnets, so mark the position of the can in the zapper, and if after zapping the motor runs the wrong way you can re-zap with the can at 180 degrees to how you zapped it before.

[Jay Guard]

If you can accurately measure the size of the existing hole (distance between the magnets) you could then just order the appropriate plug gage from Amazon. You would want to get one a few thousandths smaller to make sure it will fit but not too loose either. Should be around $8 for most sizes. The material these are generally made from may not be ideal but should work just fine for your purpose. 

[Bent Rim]

Steel slugs are available for around $10.50 in various sizes, if you have a specific size, maybe I can help you.  Send me a DM for more info.

[Mad Mark]

Great info, thanks for the help. so I tried it this morning with just an old arm for a slug and when I checked the mags with my magnetometer the one magnet read really good in my scale. Checking the other magnet it didnt seem to change and had almost no reading. Wondering if I did something wrong or possibly the machine is messed up.

[Mad Mark]

Also the can was fixed in the zapper endbell side up.

[Wink Hackman]

Maybe worth posting a picture showing how you have oriented the setup in the zapper. When I first used my Wrightway zapper I wasn't too sure which way up was correct.

[Mad Mark]

Maybe worth posting a picture showing how you have oriented the setup in the zapper. When I first used my Wrightway zapper I wasn't too sure which way up was correct.

Tired it again with no slug and got a reading on both magnets now. also tried on another can and got and increased reading on both equally so I guess my armature slug was messing it up

[Mad Mark]

Before:


After:

[Bill from NH]

In the '70s, I had no steel plugs, so used a blown .510 arm (with the wire stripped off) in a .530 C-can hole. This worked okay with Champion Arco magnets on my Russkit zapper. I used to not like crossing the leadwires, for some reason, so I labeled my zapper poles left & right. It helped keep all my motors wired the same way.

[Mad Mark]

In the '70s, I had no steel plugs, so used a blown .510 arm (with the wire stripped off) in a .530 C-can hole. This worked okay with Champion Arco magnets on my Russkit zapper. I used to not like crossing the leadwires, for some reason, so I labeled my zapper poles left & right. It helped keep all my motors wired the same way.

Yeah I gotta say all the positive, negative, north south poles, comm advance, and rotation direction of these motors still really confuses me. Think I determined North Pole is positive and theirs a red lane sticker on my zapper on the north side so that makes it a tad less confusing.

[Dave_12]

the only way to accurately match magnets is out of the can  before building the motor .  Not only to the magnets need to be matched but  you need to find out which tips are stronger then install the tips so that the strongest tips are pushing away . 

[Bill from NH]

We use the term trailing & leading edges for the stronger tips. People have debated where the stronger needs to be.

[Mad Mark]

the only way to accurately match magnets is out of the can  before building the motor .  Not only to the magnets need to be matched but  you need to find out which tips are stronger then install the tips so that the strongest tips are pushing away .

What part of the magnet is considered the tip?

[Bill from NH]

The edges, the area where most magnets touch when placed on a flat surface face down. 

[Dave_12]

On this G15 can there is more metal on the pushing side tip  to give that tip more strength . 

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[Mark Onofri]

Thanks Dave, I've been wondering about that for a while but, I thought it was just me being eccentric.

[vfr750]

I recently bought build instructions and steel cores to build a zapper. I think it's aimed more at open frame motors. Can someone kindly post a link to where I can buy slugs for can motors please?

 

Here's a link to what I have bought https://www.ebay.co....Z0AAOSw4Xpn~StI

 

Thanks,

 

John

[Mark Onofri]

Scrolling down they list one for, I gotta say it:
"You can have this magnetizer for £100 english pounds".
Or was it a magic bus?
Somewhere under this topic I've posted some old instructions for building one