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Motor winding/rewinding


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#101 havlicek

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Posted 03 December 2007 - 08:09 AM

All looks great, John.

Just need a trademark arm dye, eh.

Hey, thanks, Steve! There's enough work in these things as is. I figure that polishing the arms will be my "color". ;)
John Havlicek




#102 mdiv

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Posted 04 December 2007 - 06:57 PM

John:

You're an inspiration! :)

Now, for a picture-blessed how-to article... hehehe!

Mike DiVuolo

 

C.A.R.S. Vintage Slot Car Club

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#103 havlicek

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Posted 04 December 2007 - 07:16 PM

Thanks, Mikey... but I'm just trying to share my enthusiasm for something I think goes hand-in-hand with scratchbuilding chassis and painting bodies. I can do the picture thing, but I'm a little embarrassed to be doing something like that on a forum where some of the greats of all time are probably watching this thing with amusement. It would be better if someone like a Bob Green (I think that's his name) would do a how-to, rather than a hacker like me. I do feel pretty confident again about the whole process after all these years... kinda like riding a bike. :D

I've also started to send out a couple of these things to get some trusted opinions from people that already obviously know how to set up a motor properly. I think they're fine... now to see if others think so???
John Havlicek

#104 Hworth08

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Posted 04 December 2007 - 11:30 PM

Re-winding does fit Slotblog well but how hard can it be? The secret is properly matching an arm to a set-up that is well designed for a certain chassis, body, track, weight, driving style, and power supply, plus keeping the motor alive.

A pretty tall order.
Don Hollingsworth

#105 havlicek

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Posted 05 December 2007 - 06:11 AM

10-4 Don... and those are good reasons why winding your own arms can be such a satisfying aspect of building and running slot cars. Once set up, a person can more afford to wind a whole "quiver" of arms that suit different purposes... tracks, chassis etc. It does take a little noodling-around to get a feel for what's going on with these things and I've only scratched the surface so far myself, but it hasn't taken long to get fairly confident. I've said it before, but there's a whole heap more involved in building great a chassis like the ones you see here every day. This is easy compared to that... just that you're working on a smaller scale.

Of course, the downside is that as far as I know, these motors don't have a "home" in any organized division so they would be strictly for the fun and pride of running what you made. Sort of the slot car equivalent of a shadetree mechanic heading out to the Dairy Queen in his Nova SS that he worked on all week. :-)
John Havlicek

#106 Pablo

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Posted 05 December 2007 - 08:41 AM

I'm a little embarrassed to be doing something like that on a forum where some of the greats of all time are probably watching this thing with amusement.

I disagree. The "Greats of All Time" on Slotblog derive their amusement from seeing new people get enthused. Those who derive negative amusement from watching folks build stuff, well, they don't last long here. I've seen it. ;)
Paul Wolcott

#107 havlicek

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Posted 05 December 2007 - 09:36 AM

OK... tell you what then, Pablo. I'll do the "how to" thing (at least my method of "how-to") if you agree to chime-in and tell me when I'm doing something you think is dumb. :) Then we can have a better "how-to" that might help others. I'll be able to do another arm in a day or so and will document the whole mess with pictures. :laugh2:
John Havlicek

#108 Hworth08

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Posted 05 December 2007 - 11:30 AM

Of course, the downside is that as far as I know, these motors don't have a "home" in any organized division so they would be strictly for the fun and pride of running what you made. Sort of the slot car equivalent of a shadetree mechanic heading out to the Dairy Queen in his Nova SS that he worked on all week. :-)

Hi John!

The only home a hand-wound arm has in organized racing is in G-7 open motor racing. All other arms must be machine wound and tagged.

A "problem" with any arm under racing conditions is that they vary quite a bit, even when wound to the same specs on the same machine.

For what you're having fun doing, that doesn't matter one ounce! Most of my arm winding is Russkit 22 type motors that don't even have any brush holders. 110 turns of 34 is about the melting point, the stock Mabuchi mags are saturated at that point. Somewhat mild (to say the least) compared to your arms! Mine would be more like riding a bicycle to the Dairy Queen.

I sure don't intend to reduce the joy of re-winding but several people read these posts. I feel a bit obligated to try to define the boundaries of an arm, to make readers aware that there's a lot more to a good arm than wire size and number of turns. Perhaps the reason most active racers are glad the arms are factory-wound.
Don Hollingsworth

#109 havlicek

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Posted 05 December 2007 - 12:20 PM

Hi Don,

The only home a hand-wound arm has in organized racing is in G-7 open motor racing. All other arms must be machine wound and tagged.

A "problem" with any arm under racing conditions is that they vary quite a bit, even when wound to the same specs on the same machine.

... Yep, I kinda figured that but I would bet that if a person wanted to put in the time they could come up with a competitive wind even against those motors. I don't know anything about the "high-priced spread", but maybe coming up with the raw materials might be a problem there... but still.

For what you're having fun doing, that doesn't matter one ounce! Most of my arm winding is Russkit 22 type motors that don't even have any brush holders. 110 turns of 34 is about the melting point, the stock Mabuchi mags are saturated at that point. Somewhat mild (to say the least) compared to your arms! Mine would be more like riding a bicycle to the Dairy Queen.

... The other benefit is that for my stuff you don't need to worry about losing count past 20. I could see me getting to 75, having someone come in to say something to me and forget where I was :shok:

I sure don't intend to reduce the joy of re-winding but several people read these posts. I feel a bit obligated to try and define the boundaries of an arm, to make readers aware that there's a lot more to a good arm than wire size and number of turns. Perhaps the reason most active racers are glad the arms are factory-wound.

I wouldn't have taken your post that way at all. It may just be a matter of perception at this point... but it seems like lots more people were brewing-up hot winds in the old days (mostly out of necessity since even when you could buy custom-wound arms they were expensive). So here's this whole "retro" thing going on and what could be more "retro" than winding your own arms? Truthfully... even when the occasional "smoker" turned-up, it was all part of the fun. Now, with say a modern C-can, we have a hugely better platform to put these things in and really see what they can do. I'm thinking seriously of dropping to #23.5, #23, #22.5, or maybe even #22awg for an arm or two. What's the worst that could happen? :laugh2:
John Havlicek

#110 Prof. Fate

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Posted 05 December 2007 - 12:47 PM

Hi John

I am not sure how to relate to the people I know who only think about legal class racing. Racing is pretty low on the scale of things I am interested in. Like a lot of us on the board, I have done my stint in G7... even in the day when you DID build the arm. There is just no venue, locally, where the racing involves interesting cars. The locals run fairly stock classic.

When I travel to BP or Denver, my primary drive is associating with my friends with a little mix of slot cars in there (and model airplane flying like Lee). But in neither venue do I really worry about the competition.

I do have a lot of my OLD "serious" cars. Run them for fun, which means I still am forced to build motors to keep them running.

I admit that I sometimes play jokes. That is, I have a car with a "P" can that, ostensibly has a "Group 12" arm in it. It is sort of a test of your motor "creds". If you notice it is too SHORT for that to actually BE a G12 arm, you get a grin from me.

For me, the bench time is golden. Racing is just a sideline result of having cars.

Fate
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#111 havlicek

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Posted 05 December 2007 - 01:02 PM

Hi Rocky,

Then I guess we're birds of a feather... although I do see the benefit in proscribed forms of racing. There does after all need to be some sort of a level playing field. I also "get" just wanting to "build them and run them"!

Rick...if you see this, I got the balancer today and it's a real joy. The "extra" is a great thing as well and works like a charm. Rick made a removeable point that can be slid onto the end of the arm so that you no longer have to grind a point onto the arm itself... now that's using the old noggin!

Here's the best part, I tested three different arms I had balanced as best I could on razor blades and on every one, the R-Geo balancer consistently still picked-up a heavy side. It's noticeably more accurate than razor blades... so the arms will take a little step up in smoothness... THANKS, RICK.
John Havlicek

#112 Cheater

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Posted 05 December 2007 - 01:03 PM

What's the worst that could happen?

The worst? The arm could explode when you zing it up to high RPM and embed pieces of shrapnel in your hands, face, and eyes...

John, I think what Don was trying to say is that the winds you are using are pretty extreme. Motors with these arms are going to need a lot of power, if you plan to run them, and they're likely to get very, very hot.

That doesn't in any way mean you shouldn't play with them if you want to do so. I believe Don just wanted to suggest that those sort of winds would not be the best ones to use for running on a home or a smaller track. He was just sorta waving a flag to inform newbies and others unfamiliar with slot car motors that the winds you are using are fairly wild and would likely be way too much for many of the venues where they might be run.

Gregory Wells

Never forget that first place goes to the racer with the MOST laps, not the racer with the FASTEST lap


#113 Hworth08

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Posted 05 December 2007 - 01:25 PM

Truthfully... even when the occasional "smoker" turned-up, it was all part of the fun. Now, with say a modern C-can, we have a hugely better platform to put these things in and really see what they can do. I'm thinking seriously of dropping to #23.5, #23, #22.5, or maybe even #22awg for an arm or two. What's the worst that could happen? :laugh2:

Hi again John,

Well, true enough the worst that could happen is not much from a cost standpoint. But, 20 turns of 22 is getting close to G7 motors, and a fair amount less resistance than a G27 motor.

Under racing conditions they use aluminum endbells and Cobalt magnets along with strap cans to keep these hot winds together.

It's probably correct that the total magnetic field of today's C-can has improved quite a bit from the mid-'70s dot magnet era but I wonder if such "hot" arms can be supported by less that Cobalt magnets?

Some of you early '70s racers help out. How hot did the winds get before Cobalts?
Don Hollingsworth

#114 Pablo

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Posted 05 December 2007 - 03:09 PM

I tried to warn him, he is a speed demon and LOVES that household wire:

No problem frying your own work, it can be re-done. Endbells, unfortunately, often melt first. Just something to keep in mind...

:laugh2:

John, don't worry about being corrected in a "how-to". Just give a disclaimer "this is the way I did it..." :)

I have a special way I like to do mine; the comm always gets in my way, so I wind a pole, tag the end of the wire with a piece of masking tape "p1", a tiny spot of Krazy glue to hold it to the other windings, tag a new piece of wire "p2", leave some standing end and wind away, etc. until I have all the windings on, and marked. THEN I install the comm. That's just the way I like to do it. Others have their methods, too. It's all good. :ok:
Paul Wolcott

#115 havlicek

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Posted 05 December 2007 - 04:09 PM

OK then, Pablo... I'll get something together in the next couple of days. Your method sounds like too much work to me though! :D
John Havlicek

#116 Hworth08

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Posted 05 December 2007 - 04:57 PM

HERE'S is a thread from OWH that might be helpful for choosing winds. A thread that a person should strive to understand if their goal is to become a complete racer.

The thread is four pages and I feel it's not nice to link too much from a site that might be considered a "competitor". Excellent info though from a couple of slot racing masters.
Don Hollingsworth

#117 Cheater

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Posted 05 December 2007 - 06:02 PM

Don, we have no problem with links to other sites, as long as they're not porn sites...

Gregory Wells

Never forget that first place goes to the racer with the MOST laps, not the racer with the FASTEST lap


#118 The Bugman

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Posted 05 December 2007 - 07:23 PM

And whats wrong with PORN SITES?? :laugh2:
Oscar Morales
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#119 Cheater

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Posted 05 December 2007 - 07:49 PM

Not gonna answer, except to say not linked from Slotblog... :D

Gregory Wells

Never forget that first place goes to the racer with the MOST laps, not the racer with the FASTEST lap


#120 Hworth08

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Posted 05 December 2007 - 08:01 PM

And whats wrong with PORN SITES?? :laugh2:

Well, after watching Victoria's Secret show last night I believe the majority here might prefer just looking at arms? :) It was pretty exciting though, sorta made me wish I was 23 again! After an hour I was glad I'm 53. After another ten minutes of the Andy Griffin show I was back to normal. :unsure:

The re-winders might want to look HERE for info on modern arms to make comparisions.
Don Hollingsworth

#121 havlicek

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Posted 06 December 2007 - 07:05 AM

The worst? The arm could explode when you zing it up to high RPM and embed pieces of shrapnel in your hands, face, and eyes...

John, I think what Don was trying to say is that the winds you are using are pretty extreme. Motors with these arms are going to need a lot of power, if you plan to run them, and they're likely to get very, very hot.

Hi Cheater,

Well, when I asked the question it was sorta tongue in cheek. ;) I mean if asked the same question about using a torch to build a chassis... the worst that could happen is a gas explosion :shok: ... or getting acid flux in your eye. Playing with hot winds is MUCH safer than handling compressed butane and acid... or spinning cutting tools (a chunk of a cutoff wheel thrown from a Dremel turning at 25,000 RPM makes a pretty significant projectile!). Point taken though. :) Since I've been going through a "pushing the limits" thing here to see what's what, it doesn't serve any purpose to wind puppy-dog motors just to see if they spin. I think a valid way of getting to a consistent level of performance is to try and get close to the edge and then back away some. People do need to use common sense with all this stuff and I think that should be a given!
John Havlicek

#122 JimR

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Posted 06 December 2007 - 07:35 AM

Just as an aside -

Where does one find this R-Geo balancer that's been mentioned?
Is there a website to go to?
Jim Regan

#123 havlicek

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Posted 06 December 2007 - 07:59 AM

They're made by Rick right here... just PM him. He makes all kinds of parts and tools (I also got the winder from him) that are priced right and work! In the case of the balancer, there are a few things that make it attractive:

1) It's extremely simple yet works.
2) There are no razor blades to mess with... that alone is a plus.
3) Instead of referencing the sides of the armature shaft (where even an imperceptible amount of runout could affect what you're seeing)... the magnetic balancer is actually referencing the end of the shaft (a single contact point).
4) There's no need to have the two razor blades exactly level to avoid the armature running off them. With a single contact point at one end of the armature... you could balance the arm with it upside down (if you chose to do that for some reason).

After playing some with the balancer, it does appear that the point needs to be pretty accurately concentric with the arm shaft to get the best results. It's not super-critical, but it does matter somewhat. Static balancing (on either razor blades or with the magnetic balancer) can be sufficiently accurate to get an arm spinning smooth. It's not as accurate as dynamic balancing... but it's easily doable right at home and can produce good results.
John Havlicek

#124 havlicek

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Posted 06 December 2007 - 01:05 PM

wind_1A.jpg

OK... so here's a little run-down on how I do this stuff. Please note that this is only "my method"... and not necessarily the "correct method"... or the "best method". :) I fully expect Pablo and others here who are doing their own winds to chime-in and tell me where I'm being dumb-sloppy-lazy... whatever. I'll be illustrating what I do using a blank Mura C-can arm. These are really nice arms for a bunch of reasons, but you can do this with any blank... or by rewinding a factory arm after removing the wire and cleaning things up.

As you can see, the arm comes with a factory powder coat. This will prevent rust as well as provide some short protection where the wire is wrapped over the sharp edges of the end stack plates. I also add a couple of coats of nail polish right where the wire will wrap the stack but not out towards the ends where the spoxy will need to bond the wire to the stack. Also... you can see some overspray on the comm end of the stack. Some of this can be removed by carefully sanding or scraping it off, but I purposely leave a bit on there. It helps the comm to fit snugly until you want to fix it permanently. That way you can adjust both the overall length of the comm and the stack combined... as well as the timing of the comm and not have either moving around. Once both are set... a tiny drop of crazy glue will hold things together while working on it.

wind_2A.jpg

Next, I want to set up the arm to a known good size for my application. In this case the arm is going into a Mura can... so I match the overall length to that of a Mura arm. I usually use 1.100" as my max... the Mura being 1.098". That leaves me just enough for a washer at either end of the arm and maybe a second at one end. If you messed-up here by having the arm too long... you could always carefully trim some of the end spacer attached to the arm. As a matter of convenience (and since I don't have a timing protractor), I set the comm tab for a particular pole to be even with the following pole's leading edge. I do this step by eye, but you could also use a small straight edge or even build some sort of a simple jig that would lay against the comm tab and the pole piece's edge. They tell me this is roughly "high timing"... works for me. :)

wind_3A.jpg

The last thing I do to prepare the arm for winding (and actually... I do this before I mount the comm to avoid damaging it), is to polish it down to get rid of the powder coat on the outside. I take some #320, #400, #500, and #600 wet dry paper and lay it on my work-surface glass. I chuck the arm in the Dremel tool and start off with the heaviest... working to the #600 by running the arm across the paper at a slow speed with light to medium pressure. The dark color of the wet/dry paper makes it easy to see if you're applying even pressure across the whole arm so as not to slightly "lopside" the thing. There's a little "feel" involved here, but for such a low-tech method I haven't had any bad results. The #600 I use in my hand with the arm spinning and working with the paper on the rotation side where it won't get "grabbed" by the spinning arm... just lightly and carefully touching the arm until it shines. After all this, very little actual material has been removed from the arm. I finish-up by polishing the arm with a chromium-based polishing compound (made by Dico) since softer compounds pretty much don't do anything to steel.

... next up: the winding.

wind_4A.jpg
John Havlicek

#125 havlicek

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Posted 06 December 2007 - 01:45 PM

wind_5A.jpg

Here's all the stuff to ruin a perfectly good armature: :shok:

1) Of course... the R-Geo winder from Rick.
2) Magnet wire... here it's #24 awg and of a type where the insulation is good for higher temps.
3) An X-Acto knife for scraping the insulation from the wire where it crosses the comm tabs.
4) A bit of silver solder for soldering the wire to the tabs and a small soldering iron off camera.
5) A plastic electronics probe for pushing the wire around on the arm without damaging it (a dull pencil works great, too).
6) A "precision file" set and holder for carefully notching the solder on the com tabs so the Kevlar won't slip off when tying it up

wind_6A.jpg

... And it's off to the races. First pole is wound... trying to be as neat as possible. Note the blue (for clarity) nail polish on the top (and bottom) of the arm to add a bit of short-circuit protection where the wire passes over the sharp edges of the arms end laminations/plates. You can also more clearly see the position of the comm tab relative to the arm's pole piece. Also, when working off a spool of magnet wire, it's best to lay the spool on the work surface rather than have it standing on end. It's a little bit of a pain because the spool will roll-around as you pull wire off it... but the wire won't kink as it would standing up and coming off the spool in coils.
John Havlicek

#126 havlicek

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Posted 06 December 2007 - 01:51 PM

... So here's the whole mess all wound and carefully soldered (yes... the wire is rather stout!) and ready to be tied.

wind_7A.jpg

Then I tied up the comm and the magnet wire coming off the stacks as neat as I could with Kevlar. This stuff is great, amazingly strong so you can really yank on it when tying things up and heat resistant (a very good thing because this arm will get hot).

wind_8A.jpg

... Next epoxy and balancing/finishing touches and a little surprise at the end.
John Havlicek

#127 havlicek

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Posted 06 December 2007 - 02:55 PM

Some epoxy in a small cup, a wooden coffee stirrer to mix it with, and a toothpick to apply it. Even with non-fast-setting epoxy, the stuff starts to polymerize after a pretty short time (it starts to get a tiny bit "stringy") after mixing. I try and go slow... carefully applying the epoxy, working from the comm tabs down, but you should try and work smoothly and rapidly. I'm also applying less of the stuff now than when I started doing this again... you really only need as much as it takes to cover the windings and the Kevlar. I then put the arm in the oven, standing with the comm up and the oven set to 250 degrees at first. Even though the curing process is greatly speeded-up with heat, at first the epoxy goes through a short period where it's viscosity decreases (it becomes more "runny") so it can soak into the windings and the spaces at the comm... a good thing. You don't want the epoxy just sitting on the arm... you want it to flow sort of how you want solder to flow into a joint.

wind_9A.jpg

After a short time, I turn off the oven so as not to overheat the arm and flip the arm so the comm is down and the epoxy will run the other way. You don't have much time as the heat will rapidly "set" the epoxy. Then I flip the arm again and put it back in the oven which is now cooler... maybe a hundred degrees or so (?) and let it stay in there while the oven cools down to room temp again. Resins speed-cured this way will often be somewhat harder... but more brittle than if cured at room temp, but when applying as little as possible and having that sink-into the windings it's probably a good thing. When it comes out of the oven it looks like this:

wind_10A.jpg

... Just some balancing and finishing touches to go now.
John Havlicek

#128 havlicek

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Posted 06 December 2007 - 04:37 PM

So the idea here with static balancing is to find out which side(s) of the arm are heavy because when spinning, those heavy sides will cause vibration... bad for RPM and the life of the motor.

Here's the deal with the R-Geo balancer... the magnetic field is carrying the arm on a single point so it can rotate with little resistance. This can also be done by balancing the arm on a couple of razor blades to see how it rolls across them. When the heavy side is apparent... I mark the center of it by the top (comm) first and drill a little material away to make it lighter. You have to go slow here as the bit can slip off the side of the arm easily. What I do is rest the spinning flutes of the (small) drill bit against my thumb while just applying a bit of pressure. The bit won't cut into your thumb... but this is definitely not a safe way to do this. I don't own a small (or a big) drill press though so I improvise. The process is to try the arm... drill a bit... try it again and repeat until it has no apparent heavy side, marking and drilling as you go.

You have to be really careful not to drill too deep and you must use a narrow drill bit. The narrow bit will remove less material at a time so you don't remove too much and it will be easier to start a hole with. If you go too deep, you can weaken the arm because you'll be into the thin part that gets wrapped with wire. You could also hit the copper windings and the arm is toast. If you wanted to be safe... you could rig a drill press jig to hold the arm and set depth stops. If you still needed to remove more material after going as deep as you safely can... then switch to a bigger bit and your first hole will act as a pilot.

wind_11A.jpg

When it's all done, I rechuck the bit in the Dremel and hold a piece of #600 wet/dry paper against it to get rid of the burrs caused by drilling it as well as by engraving the wind and my initials in it, and it's ready to go into a motor. Total time about an hour and a half... I suppose I could go a little faster, but I worry about not doing a good job as I can. Besides... why rush?

wind_12A.jpg
John Havlicek

#129 havlicek

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Posted 06 December 2007 - 05:27 PM

... I don't know if this will work but here's a link to...

THE RESULT.

:)
John Havlicek

#130 Pablo

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Posted 06 December 2007 - 06:37 PM

Awesome! :good:

Questions:

- Why is only one end of the shaft tapered?
- How do you crimp the comm tabs closed without ruining it?
Paul Wolcott

#131 havlicek

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Posted 06 December 2007 - 07:00 PM

Thanks a heap, Pablo.

With the magnetic balancer... only one end of the arm needs to touch the magnet' the other floats in mid air. With this arm, I also tried trimming the shaft on the comm end to only what was necessary for the endbell bearing (plus a little) to see if that makes a difference... it doesn't. :-) On this arm, I tried both the magnetic and razor blade methods... and here they both gave the same results. Maybe I just was more careful because I was working "in front of an audience". ;)

I crimp the comm tabs closed by folding-up a paper napkin into a tight roll and placing that on the far side of the comm. I then use the needle nose pliers to squeeze the tab and the napkin... no marks and no problems. :) As you can hear from the link... it runs nice and smooth and if there were any problems at all with the comm it wouldn't.

Still... after all the work, you never know if it all worked out until you spin them up. :blink:
John Havlicek

#132 Rick

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Posted 06 December 2007 - 07:07 PM

John,

Let me look around, I can probably rustle up some old 12 arms that are good. You could unwind and wind to your heart's content. :) 12s have a .350" stack so watch the turns, it will take a few more or smaller wire or watch out! 12s are 50 turns of 29 wire. Something like a 40t/27 would be a start or some double winds...

If I had only kept all the burnt-up arms in my past, you would need a pick-up to haul them all away. Who'd have ever thunk that old arms would have any value in the future...
Rick Bennardo
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#133 Pablo

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Posted 06 December 2007 - 07:15 PM

I read somewhere the late, great Bill Steube used to file the stack thicknesses to allow more wire. B)
Paul Wolcott

#134 Horsepower

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Posted 06 December 2007 - 07:30 PM

... I don't know if this will work but here's a link to...

THE RESULT.

I don't think it works. I couldn't hear anything. :frown:

Where do you get Kevlar thread? :help:
Gary Stelter

#135 havlicek

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Posted 06 December 2007 - 08:03 PM

I don't think it works. I couldn't hear anything.

Where do you get Kevlar thread?

Hmmm... maybe try downloading the file (it's very small) and then playing it. It's just an MP3 so your computer's player should open it. Here's the LINK.
It works fine over here and was a bit of a hassle to record, convert, and post it. I'd hate it if nobody else ever heard it "sing". Just right click and "save target as" should work, then simply click on it and your computer should just play the file.

Switchblade,

I did a google for Kevlar thread and got a neat hit on Amazon for cheap HERE.

... The stuff came in a couple of days and one 50 yard spool will do a LOT of arms. Still... for a couple of bucks I bought two. :-)
John Havlicek

#136 havlicek

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Posted 06 December 2007 - 08:24 PM

Rick,

That sounds pretty cool. I don't know how easy they'll be to take apart... but I'd definitely give them a try!
John Havlicek

#137 Pablo

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Posted 06 December 2007 - 08:29 PM

Hi Gary,

Call me, I'll let you listen to it for $1.99 for the first minute... :laugh2:

It sounds like a G12.
Paul Wolcott

#138 Bill from NH

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Posted 06 December 2007 - 10:25 PM

Works okay with AOL Media Player. :)

Bill Fernald
 

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#139 havlicek

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Posted 07 December 2007 - 06:11 AM

Thanks, Bill... :)

So again, there's not that much involved here and the materials are fairly affordable. The worst part expense-wise is the blank arms and I just ordered some more from Mura and it's like $15 a pop for them (but they are excellent and the result is a better arm). The rest doesn't amount to much... maybe another buck or two per arm for epoxy, sandpaper, Kevlar, and magnet wire. Even the wire was only like $15 or so (I forget) for a one pound spool and that's a LOT of wire.

For double winds (like the #26 dbl pictured earlier in this thread)... you simply unroll enough wire onto a second spool and then feed both as you're winding. It's a little more difficult to keep things straight and neat... but not too bad. You can come up with your own signature winds... mark the arm by engraving it or epoxy-on a tag and really have a blast. For the whole retro thing, this all seems like such a natural... this was after all the way things were done before these arms became commercially available.

Finally... when you get consistent results doing this, treat these arms right and set up the motors properly. I just keep a C and D can motor handy for trying these things out and those cans are sloppy (loads of play, loose tolerances, used brushes, and beat springs), but really set-up well... these things would no doubt perform significantly better. I hope all of this helps the one or two (sigh...) folks who may be interested in trying their hand at a really "retro" aspect of slot car building, especially since it took me all day to take the pictures of the process (I'm a miserable photographer). :laugh2:

BTW... thanks a heap to Cheater for making the photos brighter and clearer so people could see the whole deal better!
John Havlicek

#140 idare2bdul

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Posted 07 December 2007 - 02:02 PM

For the whole retro thing, this all seems like such a natural... this was after all the way things were done before these arms became commercially available.

The powers that be in Retro Racing cringe at the thought of anybody having to learn about motors. :shok: It's OK to be a good chassis builder and to derive an advantage from that, but D3's RetroPro and Big Dog classes are the only retro classes that allow an individual to even blueprint their own motor.

My understanding is that may be changing in 2008 NorCal with the adoption of the 4002C as their motor and rumours of a possible anglewinder class East of the Mississippi river have come to my attention.
The light at the end of the tunnel is almost always a train.
Mike Boemker

#141 Rick

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Posted 07 December 2007 - 03:28 PM

The audio works, I was waiting for a VIDEO! (I had sound turned way down) LOL. It sounds good, turn the volume up and BTW it opens up Quicktime Player on my 'puter to run it?...
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#142 havlicek

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Posted 07 December 2007 - 03:32 PM

Rick,

The video wouldn't be a pleasant experience if my mug was on it. :shok: Better to leave it just as an audio file. :D The file will open with whatever player is designated as your computer's default audio player. It could be Quicktime, Realplayer, Windows Media Player, etc.
John Havlicek

#143 Horsepower

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Posted 07 December 2007 - 06:36 PM

Thanks for the link to the Kevlar thread! My favorite money pit - Amazon! I should have stock in them. I still couldn't get the audio. Must be somethin' with this computer. :blink:
Gary Stelter

#144 havlicek

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Posted 08 December 2007 - 07:22 AM

... No worries, Switchblade, the clip is less than 10 seconds long and it's not exactly off the Deep Purple "Machinehead" album. :D The people selling the Kevlar were cool... got the stuff cheap and fast. What are you winding? I've gotten some inquiries about doing some of these arms for people and the #24 seems to be the one so far.
John Havlicek

#145 One_Track_Mind

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Posted 08 December 2007 - 07:27 AM

Hi John,

Very nice indeed! :good:

I'm with Gary on not hearing this arm sing... but I'm sure it does very well. I get the little pop-up window and it goes for 7 seconds but I hear nothing?... Yes, I have the volume turned up.

Keep on winding and having fun! Good to see threads like this come about.

For your efforts, If you're ever in the need for a few vintage Kirkwood comms, PM me your address and I'll send some right over. No questions asked, nothing asked in return.

Slots-4-Ever
Brian McPherson

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"We didn't realize we were making memories, we just knew we were having FUN!"


#146 havlicek

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Posted 08 December 2007 - 07:33 AM

... I'm PMing you right after this. :D

Attached File  Soprano_.mp3   170.72KB   138 downloads
PS: I just discovered that the attachment system here allows audio files as long as they're under the limit so I put the "theme song" above. Maybe???
John Havlicek

#147 Cheater

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Posted 08 December 2007 - 11:01 AM

John,

No problem playing the audio file here on my old Mac.

Yes, non-image files can be attached to posts, so long as you observed the 2,000k size limit.

Gregory Wells

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#148 Horsepower

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Posted 08 December 2007 - 12:02 PM

That link did it, John! :shok: That reminds me, I have to make a dental appointment! :laugh2:
Gary Stelter

#149 havlicek

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Posted 09 December 2007 - 08:53 AM

That link did it, John! :shok: That reminds me, I have to make a dental appointment! :laugh2:


:-)...don't remind me!

Igor and I did some more experimenting in the la-bor-a-tory and did a "fuller" #24 wind (20 turns), just so people don't get the idea that I'm only interested in developing WMD over here :) . The result is really encouraging...another one that really "sings" as well. I think I'm pretty much "there" at this point and may try some heavier winds like 23awg or maybe heavier(???). The #26 double I did is really nice so I don't see the point (at least right now) in going any lighter.

I hope some of you take a stab at all this because it's great fun, not terribly difficult once you get the hang of it and really satisfying. Thanks to the ideas, requests and info I've gotten from some here, I'm also considering testing the waters doing these things as a sideline. Anyone interested can just PM me and we'll see where that goes.

-john
John Havlicek

#150 havlicek

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Posted 11 December 2007 - 08:08 AM

I'm sending out the last of my "prototype" arms today as the last part of seeing people's reaction to these things. I've sent out (from what I recall):

*a S24 15T
*a S24 17T
*a S24 20T
*a D26 13T

...just for grins some D Can rewinds with some of those.

...as a representation of various degrees of spice :-) While some of these were done while I was still gathering technique, and bits and pieces (some were tied with fiberglass for example before I got the kevlar...some weren't tied at all, and I later started using less epoxy), I think they should all run well. Hopefully, as I get some feedback on how they perform and in what setups, track conditons, chassis, and track power...I may refine them some more.

-john
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