3573 replies to this topic

[gascarnut]

What can I say, but:

MINE!!!

Thanks John, it's gorgeous and I will try to do it justice.

[havlicek]

Hi Vic and if I've got some ideas cookin' for you, I'm stoked!

But I'm not sure how you cut down the endbells and keep everything even? Is it just a matter of scribing it to the can?

Without a lathe and general "precision tooling", it's a little fidgety but can be done with sufficient accuracy. What I do is use the inside to outside measurements (thickness) of the endbell material and nibble away at the outer edge removing equal amounts from both sides until the endbell is a "snap fit". It sounds crude as heck, but it definitely works and after the first one or two, it becomes pretty straight forward. I think it takes me about 20 minutes now to cut an endbell to fit a mini motor and the cutter bits make all the difference. I use a straight carbide drywall cutout bit for the larger first pases. These have a rough cutting surface on the sides and the end, but you don't want the bit to cut on the end. I ground the end down flat with a diamond wheel in the Dremel so that the bit won't cut on the end. That way, I can let the flat end surface ride against the small lip of the endbell that stops it against the can. Then it's a matter of letting the bit ride gently on that lip and taking off material in straight/flat passes, making sure I'm not tapering the endbell. Cut a little and measure, cut some more and measure. When I start to get close, I switch to a straight spiral carbide cutter that cuts less aggressively until I get there. I sometimes finish up with sandpaper or a file, but that's usually not necessary. It sounds stupid, but it works...the thing is picking an endbell that will work since the amount you can trim on some endbells without either weakening the endbell or exposing the sides of the screws holding the hardware is sometimes not enough. Current Muras work well and I have one of those I just finished. I've also used ProSlot endbells and they work fine too, but I think I like the Muras a little better.

And once you cut it down how do you mount it, because I'm assuming you loose the mount tabs?

Easy, I drill the can and endbell for screws just as slot racers have been doing since they started fighting those silly Mabuchi endbell retaining tabs back in the Jurassic Period.

Here's the one I did today with the new Mura endbell. I also polished up the can after cutting it down because (again) shiny stuff goes faster!




These things make really neat little motors and they normally (I assume) get tossed. If you want to do rewinding, these things can take pretty hot arms and a stack length of around .330" or so with a non cut down com will fit comfortably in there.

-john

[Afterburner Boyz]

Hi John,
What do you use to remove old solder and other crud from the cans and make them so shiny? I use mounted rubber points in my Dremel tool and it works fine for removing light solder, but your cans (motor cans that is) are like mirrors!
-Andrew

[havlicek]

Hi John,
What do you use to remove old solder and other crud from the cans and make them so shiny? I use mounted rubber points in my Dremel tool and it works fine for removing light solder, but your cans (motor cans that is) are like mirrors!
-Andrew

Hi Andrew and thanks for the carbon brazing rod. Your cousin brought it here last night and it's about the same diameter as the one I've been using so it should be great. I can also get a bunch of them out of that one rod since it's so long. To remove the old solder, I use a fine scotchbrite pad in the Dremel. The I use Dico chromium polish and a hard felt wheel in the Dremel to shine up the can atterwards. If I'm going for REALLY SHINY, I'll sand the can with some wet/dry 600 before polishing and you can get an almost "chrome" like finish. Since these things will get soldered on and otherwise abused, I don't do that unless someone wants that for some reason.

-john

[Robert V.]

Hi John
I am glad you explained how you cut down those end bells as you can never have to much information, as always that can looks awsome.

[havlicek]

What can I say, but:

MINE!!!

Thanks John, it's gorgeous and I will try to do it justice.

Hi Dennis...I'm thrilled that you're going to be doing this thing up in one of your wonderful cars!

-john

[Victor Poulin]

John,
Thanks for the info. Like I said, you've given me some great ideas. I've got quite a few older F-7s in a box that one of our members sent me a while back that I,ve been waiting to find a good use for. I may have just found that good use lol. I've got a few older kelly endbells that I can experiment with, may even have a mura or two.

Vic

[havlicek]

Definitely go for it Vic. These kinds of projects are a whole lot of fun and the resulting motors are capable of some pretty great rpm's. Take your time on the first couple and you'll see that it goes way easier afterwards. I'm not sure if I mentioned it or not, but I cut the cans down so that there's enough room to insert the endbell without hitting on the magnets...somewhere around .775"...er ...give or take The old style Mura endbells have a little more room for the com and you can use a little longer arm. That's probably a good thing for heat dissipation. I think the people that ran the so-called frankenmotor thing used x-12 arms.

-john

[gascarnut]

I think the people that ran the so-called frankenmotor thing used x-12 arms.

We HAD to use X12 arms - it was part of the rules for the event.

[havlicek]

We HAD to use X12 arms - it was part of the rules for the event.

geez Dennis... these rules-makers are always stifling creativity

-john

[Victor Poulin]

Well, I at least got started this afternoon lol. I dug out a TSR motor that I had kicking around that still looked pretty good. I tried to remove the stock endbell but didn't have much luck. After a lot of screwing around, I decided to take my cut off wheel and cut the rear of the can off. It worked out pretty well. I pulled the arm, cleaned up the insides, and test fitted a ProSlot X-12 514dia short stack arm in it just to see how much room I had to play with if any. It seemed to have plenty of room, so tomorrow I'll start working on an endbell for it. I test fitted a ProSlot C-can endbell to it, and it's not off by a whole lot, so I may play around with that to see what I can do with it. I only have 1 old Mura endbell and It's like new, so I kinda hate to hack it up lol.
I know" I know" I'm cheep but I think I can make this work with a little patience and time. I,ll get back to it tomorrow afternoon and hopefully get the endbell fitted .
I,ll keep you posted.

Oh, BTW John, I also decided to try and strip down a Parma 16-D take out arm today. Let me just say that I gave up What's the secret to getting all that wire off? It kept breaking on me and after 30mins or so I got pissed and gave up lol.

Vic

[havlicek]

I tried to remove the stock endbell but didn't have much luck.

There are four tiny tabs that retain the 'endbell" Vic. Just grind them flat with a cutoff wheel (takes a second or so for each one), then tap the shaft on something and the arm will force the endbell out easily.

After a lot of screwing around, I decided to take my cut off wheel and cut the rear of the can off. It worked out pretty well.

If you scribe an accurate line (use either a carbide scribe made for marking metal or even an X-Acto blade, a fine line is best) on the flat sides of the can and then cut just proud of the line. You can then cut the curved sides safely away from where they will need to be just "by eye". Then switch to a cutoff blade that is bigger than the end of the can and start holding it's flat against the ends of the can and flip the can after a few seconds. Keep doing that until you see you've reached the line on both flat sides and you can see that the swirl marks of the cutoff wheel are even across the whole can end and you should have a nice square end.

I know" I know" I'm cheep but I think I can make this work with a little patience and time. I,ll get back to it tomorrow afternoon and hopefully get the endbell fitted .
I,ll keep you posted.

No...you're not cheap, you're doing something crafty. It's easy to buy motors and then toss them when they're toast, what you're doing is much harder!

Oh, BTW John, I also decided to try and strip down a Parma 16-D take out arm today. Let me just say that I gave up What's the secret to getting all that wire off? It kept breaking on me and after 30mins or so I got pissed and gave up lol.

Sometimes I'll let the arm sit in methylene chloride for a while, rinse it off in water, dewind as much as I can and then soak again. Major pain in the butt, so I usually cut the wire off and pull it out in chunks with a needle nose plier. I have other ways of doing it too, but they're kind of dangerous so I don't share those

-john

[gascarnut]

geez Dennis... these rules-makers are always stifling creativity

-john

Well, at least they did not specify WHICH X12 armature you had to use, so I ended up with one of the new big diameter ProSlot arms. It took some work to get it into the little ProSlot can, but I did it. It wasn't much better than anyone else's motor though!

[havlicek]

Well that's something anyway!

-john

[Victor Poulin]

There are four tiny tabs that retain the 'endbell" Vic. Just grind them flat with a cutoff wheel (takes a second or so for each one), then tap the shaft on something and the arm will force the endbell out easily.

-john

DUH !!! I don't know why I didn't think of that I was trying to pry the tabs back with a small screw driver and mallet with no success at all lol. I,ll remember to try that on the next one

Vic

[havlicek]

I finished-off the arm for the last hot rod I set up, another in my "mixed-nuts" series. Again, it's a #26 awg and smokin' hot, but runs really smoooooooth. This time with a new Mura endbell cut to fit the mini motor's shortened can.




-john

[Victor Poulin]

I finished-off the arm for the last hot rod I set up, another in my "mixed-nuts" series. Again, it's a #26 awg and smokin' hot, but runs really smoooooooth. This time with a new Mura endbell cut to fit the mini motor's shortened can.




-john

NICEEEEE John !!

[Victor Poulin]

Ok John here,s mine !! I got it all finished up this afternoon. It's not quite as pretty as yours, but I think I,ll get better as I go along here. I used a ProSlot 514Dia Contender arm with 38deg timing, cut down ProSlot C-can endbell, with ProSlot brushes and Champion light springs. This thing is scary !!! It is unbelievable how much power and tork this has !! At 4 volts it's drawing 2.6 amps and is screaming. I,ll be building many more of these that's for sure !!

[havlicek]

Hi Vic...that looks aces! Yes, the Contender arm is a whole different animal when you feed it to some stronger magnets. It looks to me like you did a fine job and they DO get easier as well as even a little better as you do more of them. Congrats!

-john

[Robert V.]

Nice work Vic i am glad to see you have joined the rewinding club we need as many memebers as we can get, keep up the good work.

[Victor Poulin]

Hi Vic...that looks aces! Yes, the Contender arm is a whole different animal when you feed it to some stronger magnets. It looks to me like you did a fine job and they DO get easier as well as even a little better as you do more of them. Congrats!

-john

Hey, I owe it all to you John,your the one who came up with the idea I just followed your lead. The hardest part was trimming down the endbell and making sure I didn't take to much off at one time, so there was a lot of trim fit, trim and fitting going on lol. I,ll tell you what, this thing will make one heck of a drag motor! I,ve still got to weigh it, and I,ll do that today and let you know what it is, but I know it's not much.

Vic

[Victor Poulin]

Nice work Vic i am glad to see you have joined the rewinding club we need as many memebers as we can get, keep up the good work.

Thanks Robert, I still have to tackle my first rewind though. I'm waiting for some supplies to get hear that I ordered. Heck, I'm still working on dewinding a Parma 16-D arm lol. What a pain in the butt that is!!

Vic

[havlicek]

Hey, I owe it all to you John,your the one who came up with the idea

NOOOOOOOO Vic. Lots of other people have been cutting down and improvising various combinations of parts to make one-off motors probably since day one, so this was in no way my idea. I had done mostly C-can cut-downs and a few weirder motors, but hadn't used the mini motors until not long ago. The neos in these motors make some very small, light and powerful combinations possible. The only downside I see is that neos don't do so well with heat and the less strong ceramics tolerate the heat OK. Then there's the cobalts ...

Anyway, you did a fine job there, nice work!


-john

[Victor Poulin]

Thank you very much John, coming from you, that means alot to me!! Your a good teacher and devote a great deal of time to showing people like myself how to do these projects. Years ago, people like yourself would very seldom devote the time you have to teaching people like me who want to learn, and I thank you for that. I'm also sure that this thread gives a huge boost to scratch builders who like me, may otherwise not have the balls to go for it and give it a try. Like I said before, I DO owe it to you, and I look forward to doing much more with your teaching.


Vic

[havlicek]

No thanks necessary Vic. I got a little chuckle out of your comment about how few would share this stuff years ago. My experience was that people would hold onto information like it was some sort of state secret and that if they told you anyhing, they'd have to kill you afterwards! Funny that when I started noodling around with this stuff again a few years ago, I was using Mura G20 motors and as nice as they are..."something" was missing. Then I started looking at winding again and, despite the endless "advice" (ad nauseum) that it was pretty much a waste of time as factory arms were the way to go, I've gotten a lot of enjoyment...and even a little success out of doing rewinding again. I have zero problem sharing this stuff, in fact I get the biggest kick of all from seeing others tear apart motors and have at it. So I'm really stoked if I may have helped even a little to get people to look at motors again as something to dig into...instead of just toss when they're blown. Having said that, I'm always looking for used TSRF/S7/F7 whatever else they're called mini motors. If anyone else is looking and has some, PM me.

-john