3573 replies to this topic

[havlicek]

I have gotten some questions about the crank shown in the above pictures. I keep two cranks with a couple of different clamps for each. One is a RGEO that I do 26D and 36D arms with using a Rick clamp I modified to fit 36D and a LaGanke clamp made for 26D. That crank works great, but after working with it, I wanted some slight changes and built those into a separate crank. The second crank has a shorter crank arm, but more importantly, the shaft is threaded all the way from the clamp to the crank arm. This allows me to dial-in some "drag" so the arm doesn't flop if I have to let go. It also makes it easier to manage tension while winding. The brass clamps were given to me by a Blogger (I think it was Dave Reed a long time ago...thanks again Dave if it was you!). They're perfectly machined and I have two of the brass clamps. One I slightly modified so I can clamp from all the way down to around .475" diameter arms, and the other will clamp arms up to maybe as much as .520" or so.

-john

[Kim Lander]

John,
Russ Crites is a buddy of mine here in Ga. we used to run slots together then he dropped out for a while then got back in it big , especialy the drag racing, he is a genious at machine work so he will be a good student at rewinding.He is always hungry for knowledge, by the way, the winds are still looking better every time...seeya ...Kim

[Dave Reed]

I have gotten some questions about the crank shown in the above pictures. I keep two cranks with a couple of different clamps for each. One is a RGEO that I do 26D and 36D arms with using a Rick clamp I modified to fit 36D and a LaGanke clamp made for 26D. That crank works great, but after working with it, I wanted some slight changes and built those into a separate crank. The second crank has a shorter crank arm, but more importantly, the shaft is threaded all the way from the clamp to the crank arm. This allows me to dial-in some "drag" so the arm doesn't flop if I have to let go. It also makes it easier to manage tension while winding. The brass clamps were given to me by a Blogger (I think it was Dave Reed a long time ago...thanks again Dave if it was you!). They're perfectly machined and I have two of the brass clamps. One I slightly modified so I can clamp from all the way down to around .475" diameter arms, and the other will clamp arms up to maybe as much as .520" or so.

-john

Yes John it was Me.. Very glad you have been able to use them so much..Its great that you have set others out on this rewinding trend..

[John Miller]

By the way, that the motor manufacturers charge what they do for either machine or hand wound arms never ceases to amaze me. Even setting up for production runs to keep costs low, the time, materials, R&D, tooling and effort involved to make slot car motors is significant to say the least. Without knowing the economics of it all, I feel confident that none of them are getting rich doing this stuff. People walk into a track and pick an arm or a motor off the shelf, and I wonder if they understand what a bargain they're getting. It's one thing to do this as a hobby...very interesting, challenging and fun, but to make a profit off this as a business must be torture! Hat's off to all the manufacturers...big and small!

-john

I believe that a lot of folks over look this in our hobby. The same goes for the track owners too.

[havlicek]

John,
Russ Crites is a buddy of mine here in Ga. we used to run slots together then he dropped out for a while then got back in it big , especialy the drag racing, he is a genious at machine work so he will be a good student at rewinding.He is always hungry for knowledge, by the way, the winds are still looking better every time...seeya ...Kim

Thanks Kim

Yes John it was Me.. Very glad you have been able to use them so much..Its great that you have set others out on this rewinding trend..

Whew...glad I got that right Dave Those two clamps have been a real joy. Whoever machined them got it perfect and brass is an excellent choice because it has a natural "slipperiness" that makes it easy to insert and remove the arms from such a tight fit clamp. Thanks again VERY much Dave...I use them every day for 90% of the arms I do.

I believe that a lot of folks over look this in our hobby. The same goes for the track owners too.

Absolutely John!

-john

[havlicek]

I haven't done a D motor arm for a while, so I figured I'd post up an arm I finished for my buddy Brian McPherson. This one was on a Bugenis stack and com with a drill blank shaft. The stack cleaned-up at just about .560" diameter leaving about .010" per side (.580" hole...Parma D motor). Brian left it up to me as to the wind, so I did him a #28 "hemi". After screwing around with the number of turns and patterns for a while, I came up with this:



I went a little heavier on the epoxy than I normally do, just because the coils seemed like they could use a little more support...especially up by the com. I spoke to Brian about maybe sending it out for dynamic balancing if the static job I did didn't seem close enough. This one was a "one hole" balance job on my RGEO balancer and it seems to run pretty smooth...so I think it's fine as-is. No doubt a good dynamic balance job would be even better, but he's good to go

-john

[Gary Lum]

John, that is a work of art, Sir! Man, I'm drooling over here! Thank you for posting and shraing your work!

[havlicek]

Well heck...thanks Gary. The big ol' D motors are a great value, and with a little persuasion can be faster and funner. There's a lot of potential in these motors to have a good boost in performance without getting crazy. This one sounds really strong, but is no flame-thrower. It draws a little over an amp (no load/5.5V) and after 5 minutes "quickie-break-in" was still pretty much cold. I guess that changing those weird stock springs for something stouter would up the amp draw (and performance), but it should still be fine. I worry a little about the hemis because the wire often winds up a little away from the com, but I tried to take some extra precautions to keep it all together.

Being a "one-off-no-tag" arm, this obviously isn't destined to be raced, but I hope Brian has a bunch of fun with it.

-john

[One_Track_Mind]

Hi John,
That is really a humdinger of an arm!
Really Nice!
Thank You!

[havlicek]

You're most welcome Brian I'll send it out to you tomorrow.

-john

[Russ Crites]

Hi John,

I did as you suggested, I read through the first 50 pages of posts, but found nothing that helped me as much as your postings on this page this week, as well as, the cutting of one of my armatures apart. Thanks again, and by the way the armatures do look great.

Russ

[havlicek]

Hi Russ. Glad you've been able to get some of the info you need!

-john

[Alchemist]

"The next few posts will be a condensed "step-by-step" of rewinding."

Even though I read and re-read the information in this thread - I am just excited to see more pictures and info!

Thanks for your time John! Hope all is well buddy!

Ernie

[havlicek]

Right back at you Ernie!

-john

[havlicek]

So I've been on something of a quest for a few weeks to do a motor using the solid neos for Chris Walker with some parameters that made it a little difficult.

*Do a motor that makes good use of the very strong field these magnets generate. It's really easy to do a mild wind like a #31 and have the motor not run too hot, but a wind like that doesn't do anything with the potential of these magnets. In other words, the motor is working too hard just to turn over and you could do a much hotter wind with modern ceramics as thin as these are, and still have the motor live a happy life without self-destructing from heat.

*Do a motor that could be at least fairly practical in a road type car as opposed to a drag car. We've seen some pretty hairy setups with solid neos configured so they put out a lot more field than even these...but those motors wouldn't last very long doing laps.

*Do a motor that could easily be installed in any number of chassis without having to solder it in. These magnets have a lower heat tolerance than ceramics, so doing a no-solder install is a good thing.

*Get rid of the heat as best as possible. Stronger magnets mean more heat.

Keeping all of the above in mind. I've experimented with various arms and setups. I've probably built a half dozen motors and more arms than that trying to do a motor that made good use of what these magnets can do...but for more than drag racing. It's a tough nut to crack without either just doing a very mild wind...or...just opening up the airgap which would be a waste since you could just use ceramics and run a typically tight hole. This is what I ended up with:



The arm is a Bugenis .560" cut down to a .350" length with a Bugenis com . That leaves somewhere around .010" per side between the arm and the magnets. The wind is 42/28 with a mild advance of around 15°. The end bell is a Pro Slot I guess from one of their smaller motors (I think they're called the euro something-or-other), and it's a really nice piece. It has taller spring towers which is important to allow for better springs, and the bushing carrier part of the endbell does a better job of firmly holding the bushing than say the Hawk endbell. So the end bell is similar to the Hawk, but has a couple of nice improvements that give it an edge...I think.

The can was originally from a TSRF motor. Like all these type motors, it's one-piece (no seams or welds), surprisingly well-formed, and the steel is both thick enough AND strong enough to be fairly sturdy when hacked to pieces like this one has been. I cut the length of the can down to .750", removed the top and bottom for the "strap" like design to allow for the best airflow and cooling I could get. These magnets are plenty strong enough with no can at all. I finished it up by installing a new oilite after reaming the bushing hole out. The standard hole pattern should make installing this motor without having to solder it in a snap. You "could" solder it in after using screws to install it if you were really careful and didn't linger on the can for long, b ut it should be OK as-is. Magnets are of course epoxied-in with JB Weld Marine Formula that says it's good enough for something like 400°F. I did score up the back of the magnets a little to give the epoxy something better to hold on to, but it was fiddly as heck to get these things installed semi-accurately. I just hope enough epoxy strayed on the back after sliding them around several times to get them lined-up and locked in while the epoxy cured. They seem fine and I did do some banging on my glass work surface to "test" out the bond.

After a break-in of about 20 minutes, it probably averages somewhere around 2 amps current draw (no load @ 5.5 indicated volts) and stays cool enough to hold with my fingers without any problems...but it does get warm. It spins up and down like turning on a light switch and wants to jump when doing so and has loads of RPMs as well. The stack length seems right for the size of the magnets, and I'm not at all convinced that a few more lams would make things better. The result is a compact little powerhouse built on the cheap out of easily obtainable parts.

-john

[Coal Train]

Very well done John,
I feel your pain towards instaling the magnets and something I've learnt when making a key-way is it's better to remove all of the nickle and copper
as if the mags are going to come loose it will be the copper coming away from the actual mag material .
You say 42/28 , whats that in ten year old kid terms so I can understand the turns and gauge.
Now only thing to do is find one of those TSRF motors to destroy , looks like you've found a way cheaper way of building a motor that can quite posibly
be able to beat my motors and it's screw in , once again very nice job and I think I'm going to have a lot of fridge magnets.
Your motor even looks very similar

[havlicek]

Oh I doubt the motor would in any way beat your motor Robert since it was built for a different purpose. It seems like it would be very quick off the line and have good top end, but it's certainly not a drag motor I'd porbably have gone with a #24 or even a #23 wind for that purpose and cast all doubts to the wind, tightening the airgap even more. Still, the motor does seem (at least for now) like it could live in a road-race type car.

Now only thing to do is find one of those TSRF motors to destroy

Since motors of this type are disposable, there should be plenty around that would normally get tossed into the trash. They have some neat things to fool around with. The stock magnets for example are the polymer/matrix type neos and they fall somewhere in strength between good ceramics and the solid neos. Some of the really early ones ("Falcons") had some very nice ceramics that were quite strong for their size and thickness. Those in particular make for some very good Mabuchi 13UO rebuilds. Even the arms can be easily used for winding for some types of motors as they have a very durable coating on them.

You say 42/28 , whats that in ten year old kid terms so I can understand the turns and gauge.

That would be 42 turns of #28 gauge wire, which is a couple of turns off a pretty standard #28 wind...but in this case on a short stack. As I'm sure you know from the work you've done with these magnets, armatures you thought you knew behave very differently behind this much magnet. Very nice work on the motors BTW...they look like VERY serious business!

-john

[Coal Train]

Yeah like I said , if I was going up against your motor even though youve built it for roundys I sure would still be concerned
It looks angry.

[Gary Lum]

John, funny that you mention mild winds with serious magnets.... I was talking with Jeff Easterly this weekend about different winds and how they would run with neos.... Of course, it would be drag related, but we were tossing around some old double and triple winds from back in the 70's and 80's.... Ok, I wasn't really old or hip enough to know about the double and triples other than what my cousin told me that he used to run during those times.... I really enjoy sitting around and talking with Jeff as he always gives me a different perspective on winds and motor building. Sometimes, when you are locked into a certain way of thinking and someone has a different perspective, well magic can happen!

Keep posting those awesome builds! I really appreciate all that you are sharing!

[havlicek]

Yeah like I said , if I was going up against your motor even though youve built it for roundys I sure would still be concerned
It looks angry.

I like the way you say that Robert...from one motor guy to another, I admire your "balls-to-the-wall" approach

Keep posting those awesome builds! I really appreciate all that you are sharing!

Thanks Gary I'll post stuff every once in a while when it seems like it's something a little different from the same old stuff I've posted many times before. I'm not so sure about double and triple winds with these magnets, especially for drags. After all, the whole point of the multiples is the softer torque characateristic along with the high revs. I think that all-out big wire arms would be the ticket for that application. For road cars, these magnets are very difficult and a single mid-wind like a #28 - #29 seems about right, and even that is "on the edge". This sort of underscores to me that the polymer matrix type neos used in the "Falcon" and similar motors was an excellent choice for the purpose. I would almost bet that choice was made not to make a cheaper motor, but because the solid neos are just too much magnet for the application, and because the matrix type neos are still a step up from ceramics.

-john

[Marty N]

Low timed (22*) 65 turn 30's ran very well in Emovendo magnet set ups. Basic Hawk wind. 55-60 K rpm limit and around 110 watts peak power. John you built several of those for me that ran really sweet in light cars.

[havlicek]

Low timed (22*) 65 turn 30's ran very well in Emovendo magnet set ups. Basic Hawk wind. 55-60 K rpm limit and around 110 watts peak power. John you built several of those for me that ran really sweet in light cars.

Hi Marty,

Interesting that we both seem to keep landing around the same place on these setups...even though they're for different purposes. I could easily see a 65/30 being an excellent wind and putting out much more than the same wind in a ceramic setup. I have some more of these magnets and was planning on going to milder winds as I think the #28 (maybe a #27) is about as hot as would make "sense" (as if there were such a thing for this stuff ). The only thjing I haven't played with are doubles, and at some point I plan on doing a double #31. With the high revs/lighter brakes common to the doublewinds, the solid neos might just be a very good compliment. A double #31 being "somewhere around a #28 sgl", makes it seem like it should be do-able on paper...but we know these magnets have a way of changing things

-john

[havlicek]

After some quick and dirty testing with as single setup and multiple arms all wound and built the same except for the lams, I have a new favorite lam...and it isn't .007" thick either! It's one of Bill Bugenis' .014" lams, and you could have knocked me over with a feather. There...I just wanted to say that

-john

[Coal Train]

You kinda sound excited for some reason

[havlicek]

You kinda sound excited for some reason

Well I am .007" lams/arm blanks are hard to come by. I'm not even going to try anymore since these seem so close for the majority of arms I do for people there's no reason to look anymore. I would guess that there are applications where the .007" lams have a slight edge, but these work great!

-john