3573 replies to this topic

[havlicek]

I did-up a minty FT36D as part of a large group of motors and was really pleased with the result. I like doing motors within the limits of the original and this one is a good example. Taking the motor apart, one pole had 116 turns, another had 106 turns and the third had 105 turns...and the arm was definitely stock. I think someone wasn't paying attention in Mr. Mabuchi's factory or something Anyway, the magnets were surprisingly not too bad in this motor, so I did 85T/#30 awg for the wind. I've used this before on FT36D motors and it's a solid upgrade from stock but really doesn't make any endbell strengthening necessary. The wind will work fine with good stock Mabuchi mganets or better with Arcos, a nice way to go. Other than that, I flattened the magnet stop tabs at the back of the can a little so I could better center the arm in the field, replaced the original splined shaft with a drill blank and used a Tradeship com (the one with a built-in 22 degree advance). Of course, I also put a bend in the end of the springs so they better contact the brushes as we always did back when these motors were...new! The motor runs strong and cool, drawing only around .6 - .7 amp and should calm down even more after a break-in. I like it!



-john

[Victor Poulin]

Looks super nice John, you counted the winds during the dewind?? How the heck did you manage that lol ?
I dewound an american 16-D arm last night, and no way could I have counted the turns even if I had tried The wire came off in hunks of wire and epoxy Man is that a bitch

Nice job on the 36-D

[havlicek]

Thanks Vic

you counted the winds during the dewind?? How the heck did you manage that lol ?

Pretty danged easy with a Mabuchi since the coils are uncoated. It also made "dewinding" easy as pie back in the day!

-john

[Robert V.]

Hi John nice work on that 36d as always, i finished winding my 26d with 22 turns of 29/28 ran very smooth lots of rpm but pulled 3.5 amps and ran very hot so i rewound it again with a 29/29 25 turns still ran very good but pulled 2.5 amps better but still to high and ran a little hot, any thoughts on this, for now i think i may ditch the doulbe wind idea and do a single as i want the motor to go in a thingy car with a custom chassis i will build myself and i want it to run for a while with out the motor cooking at that amp draws it would not last long.

[Victor Poulin]

Hi John nice work on that 36d as always, i finished winding my 26d with 22 turns of 29/28 ran very smooth lots of rpm but pulled 3.5 amps and ran very hot so i rewound it again with a 29/29 25 turns still ran very good but pulled 2.5 amps better but still to high and ran a little hot, any thoughts on this, for now i think i may ditch the doulbe wind idea and do a single as i want the motor to go in a thingy car with a custom chassis i will build myself and i want it to run for a while with out the motor cooking at that amp draws it would not last long.

Robert
Try swaping out your springs and or brushes. I just had the same problem with a custom Neo group 20 motor I built. At 5 volts it was pulling 5plus amps and running very hot. I went to different springs and brought it down to 3amps. After 20minutes or so of running, it settled in at 2.7 amps at 4volts and ran much cooler.

Vic

[havlicek]

Hi Robert,

Vic could be onto something as the springs could very well be too heavy for the motor...worth a try. In any case, I do around 30 turns of of #29 double for 26D and that's still a pretty smokin wind. Personally, without doing major modifications to them...I think #30 double winds are safer for Mabuchis. If you have Arcos in there, then #29 doubles are fine with enough wire on there. More on the springs; double winds tend to have more revs but less torque than "equivalent" single winds. Using too-light springs can result in a motor that has lots of RPMs and not much torque at all.

-john

[Robert V.]

Thanks guys, i used a NOS pair of Mabuchi springs as they are pretty weak i think it must be to few turns with wire that's to big, i have already rewound the arm with 52 turns of 28 gauge single and it spins real nice and pulls about 1.5 amps not to bad and it runs a lot cooler i am waiting for the epoxy to dry then i will heat cure it and post pics, next time i try a double i will go with the 30 turns of 29 on a 26d as John suggested.

This arm winding is a learning process that never stops, i have a 36d arm stripped now John what would you suggest as a double it will have stock Mabuchi mags but i guess i can shim them for a little extra help.

[havlicek]

Hi Robert,

When you try the doublewind 26D again, 30T of #29 double should be the minimum. The limiting factor on the 26D is the shortness of the stack so things tend to pile up on the top and bottom. I do pretty much the same wind with the smaller FT16D as well. On the 36D with stock magnets, I don't think anything more than a mild wind (single or double) is advisable. The one I just did was 85 turns of #30 single, and it was a nice upgrade from stock, but still safe. Unless the motor will be for a drag car, I wouldn't do anything hotter than a #30double or a #31 double...and either of those would probably need post protectors at least to keep the springs from melting through the posts. An FT36D with stock magnets and endbell might be able to live with 45-50 turns of #30 double...but that's going to be somewhere near a #27 single wind and that's right on the edge of what the motor can take.

-john

[Robert V.]

Thanks John on the 36d i think i have 2 small rolls of 31 gauge silver wire i will try that maybe 55/60 turns if not a double 30 with 50 or more may work, i will keep you posted.

[havlicek]

Part of another large group of motors was this Mura B motor. This is one of the several kinds of "B" motors I've seen, and this is the type with the clearance milled into the inside of the can for the arm. Needess to say, these are short/squat/tight setups and with the very limited cooling provided by the can and endbell, it's easy to see why they had a reputation for getting "warm" In any case, I really like these old Muras (also the Mabuchi-looking one before this one...not sure if they called that the "A" motor or if that tag was added later on or what). Anyway, the can had been painted right over some heavy rust and pitting, so I had to take it pretty far down to get to semi-clean metal, and then shot the can yellow. The endbell was super clean and the owner supplied me with some non-correct hardware that he wanted on there (an attempt to head-off the period-correct police ). Since they're a direct retrofit, I added a pair of the bottom heatsinks figuring they couldn't hurt with the "B". A nice new/tight can bushing completed the setup.

For an arm, I used one of my last thin-lam vintage arms and I don't know what make it was originally, but I hadn't seen this one before. It's not a Mura, even though the com looks like it is, and even though it has a similar thick web, the crown of the poles is back-radiused to allow for a bit more winding room. The insulating coating on the arm is brown, if that's any clue for the literati out there what or where this arm came from. Anyway, the shaft was shot to heck so I replaced that with a new drill blank and off I went. For a wind, I figured I'd do a relatively "safe" #28, again keeping in mind the "B" motor's reputation and I kept the advance moderate. After a final polishing, the arm came in at around .510" diameter and boy are the clearances in the setup tight! After a short break-in, the motor draws about 1.5 amps, runs super-duper smooth and has lots of revs and torque. The wire doesn't have to be really fat for a pretty impressive result and this motor sure proves that. Anyway like I said, I dig the "B" and the motor came out awfully nice...even if it isn't 100% correct:



-john

[Robert V.]

Hi John

Cool Mura B i haven't seen one of those in a long time didn't realize they were that short.

Time for a few rewinds of my own first up a Champion 26d 52 turns of 28 gauge pulls 1.2 amps and runs pretty cool it's also one of the smoothest running motors i have rewound and it's not even balanced guess i got lucky gave it the full rebuild new end bell, cement, tied, epoxy, heat cured should make a good runner, next up a Dynamic 16d rewind 70 turns of 30 gauge gave the arm the full rebuild same as the 26d except i replaced the gimble bearing with a Parma 16 bearing and a brand new end bell as the old one was in very bad shape, i know 70 turns of #30 is not a high performance rewind but i built this one for 2 reasons one to give it that period style rebuild and the second reason for next years dynamic thingie challenge and it will have to last a long time with out going up in smoke the motor pulls .9 amps and runs nice and cool but what i don't understand is it really spins a lot better than i would have thought maybe it's those Dynamic magnets which seam to be a lot stronger than standard Mabuchis mags, i also left the ugly green dirty paint and the dynamic sticker on to give that well used look.

[havlicek]

Hey nice motors Robert! They should both be strong runners, and I particularly like the Dynamic as I think I've only done a couple of those and don't get to see them often. You're on a roll, keep 'em coming!

-john

[Robert V.]

Thanks john i know you like those old 16d's and i though that Dynamic would make an interesting build, next up i think i have a few more of those old 16d chrome can Mura's the one's with the really strong magnets, or maybe a 36 ddouble wind i have to check the stash.

[havlicek]

Yeah Robert...those 16D Muras are pretty cool motors, and with much better endbells!...but I like 'em all!

-john

[Victor Poulin]

Nice job once again Robert! !

Vic

[havlicek]

Something that comes up from time to time is that people will often PM me asking for advice about a motor setup question, gearing...or a wind for a specific track etc. Really, I take my cues from the racers and it seems to me that's really how it should be. I'm not out there racing and don't have the experience the racers do regarding all the variables. Mostly, I either get an idea from what people tell me...or do a specific wind or setup on their direction. Without the racers, I wouldn't have a clue!

-john

[Bill from NH]

Tell them to use a small tooth pinion(6-8T) then go track test their car. For a 36D, 12-14 teeth on the pinion would be considered small.

[Victor Poulin]

Hey guys,
I just finished building up another Falcon 7/ group 20 drag motor.

I started with a Falcon 7, striped it out and opened up the can a bit for cooling. I installed a new set of XMOD neos. I used a Proslot endbell that I trimmed down to fit the falcon can. I went with new Mura hardware and Slick 7 ball bearings.

On this one I used a Proslot 45deg group 20 arm. I thought it would make a great drag motor, and it sure sounds like it's going to !!
It pulls around 3amps @ 5volts and just screams.

I hope you dont mind that I posted it over here John, but most all the people who are into this type of build are here on the winding thread lol.

[havlicek]

That sure looks like a potent little sonofagun Vic! Those Xmod neos are ridiculously strong and it's almost frightening how the behave in a setup. With a wide air gap (wider than seems "right"!) they just pull like crazy. Tightening up the air gap to what would be "normal" makes it hard to spin the arm by hand. Really nice motor

I hope you dont mind that I posted it over here John, but most all the people who are into this type of build are here on the winding thread lol.

Not at all! There isn't much more I can show here that I haven't shown many many times before, so it starts to get boring. I thank you for keeping things interesting!




-john

[havlicek]

Tell them to use a small tooth pinion(6-8T) then go track test their car. For a 36D, 12-14 teeth on the pinion would be considered small.

That's really about all I could say with confidence Bill. The guys who have real motor programs going have tested all the variables on the car...tires, lead wires, shunts, brush types, spring types and weights, magnets, air gap, can type etc....against all the track variables...power, lane length, straight length, track surface etc. and with their controller(s). It seems more "right" that they'd be telling me what to do! Like I said, I wouldn't have a clue without them.

-john

[Don Weaver]

......so it starts to get boring.

Not for me, John. Look forward to seeing your handiwork. I've noticed that the two chassis' (Dynamic Challenge and the Puzzle Pan) you've posted pictures of are right up there with your motor skills.

Don Weaver

[havlicek]

Not for me, John. Look forward to seeing your handiwork. I've noticed that the two chassis' (Dynamic Challenge and the Puzzle Pan) you've posted pictures of are right up there with your motor skills.

Thanks Don, I wouldn't want to categorize my "skills" at either motor or chassis building, but I can get things done anyway For chassis builds, there are a whole bunch of guys here who's skills I really admire and would love to be able to emulate. I'm not really setup for building serious chassis and don't even own a jig...just a big old piece of glass, a Dremel and some pliers.

On the motors, it just seems to me that posting the same builds gets repetitive and I'm not really informing so much as just using bandwidth. For example, here's a large batch of vintage motors (*except for the two D motors...and even those are older examples) I just finished off to be sent to europe. None of them are anything that I haven't posted here many times before. This batch is a particularly nice one, and all the motors have NOS and very clean restored parts, but these builds alone would account for another 10+ pages in the "Arm-Winding" thread. That's why I don't post a lot of the stuff I do. I do like to share the builds, but never want to wear out my welcome here at SlotBlog!



-john

[Prof. Fate]

Hi

John, the other day Charlie Nelson and I were at dinner with his wife and a couple locals. She was BAFFLED by the conversation which mostly revolved around discussing a new motor of mine that I have. It wasn't FOR a project, it was just something that I had to have for it's beauty. She didn't get it!

But in fact, for some of us, the idea of "same old..." isn't the issue. I like looking at your motor work as a form of art if nothing else. So, don't go to that place, just let us enjoy.

Fate

[don.siegel]

Amen Rocky!

John, if you have any more "motor porn" pictures like that we want to see them: just put on a raincoat and sell them under the counter - hmm, how's that for a mixed metaphor?

I'm with Rocky, I like looking at your work on these old motors, and believe me, wives aren't the only ones who don't get it... I always remember a couple years ago, when I got an old slot car from England and brought it in to my office, proudly showing it to my younger Australian colleague, who cried out, "You paid 40 quid for that????" And if I had just showed him a motor, he wouldn't even have known enough to be surprised...

Don

[havlicek]

Thanks Don and Rocky. I'll keep posting builds here and there, just try and keep it interesting and not so repetitive.

-john