3573 replies to this topic

[don.siegel]

Motors that move in the night? Stacks that shift with no known cause? Windings that creep?

You guys are scaring the bejeebers out of me!

But a fascinating tutorial none the less - okay, next time I wind an arm (by 2015, no later!), will it bite me?

Don

[havlicek]

okay, next time I wind an arm (by 2015, no later!), will it bite me?

Only if it's a #23 awg Don

So I got the Pro Slot endbell kits today and of course Mr. Murphy saw to it that one of them had two of the same brush hoods Lucky thing I ordered two. Anyway, I shaved and fitted the C can endbell, assembled the hoods, reamed out the end so the bearing is exposed (looks much better) and drilled the can and the endbell. Now I have a solid setup with ball bearings on both ends that should be a really nice platform to rewind the arm and install it in. This is going to be good!

-john

[Slotgeezer]

AWESOME!!!!

[havlicek]

Hi Jeff,

Thanks again for the encouragement If I get the time today, I've decided to go for it and do a #27 awg wind on this thing with a salvaged com from a Mura G20 arm (thanks Barney!). I don't know if these magnets are up to the task, but I'm not going to short-wind this thing as a little bit of insurance. I'll remove a bunch of lams from this (very) long stack to get it down to around .465" or a bit more and try and keep the arm at .3 ohm and see what happens. I'm in uncharted waters here, but I can always wind another one

-john

[HarV Wallbanger III]

Hey John when I get abck I'll send you some mags to play with for these. I hope you got the labels. The clear one are in the plastic heat sealed paks. Looks great!

[Prof. Fate]

Hi

John, in the day when we were doing 27s as the upper limit, the ceramic magnets in our 16ds weren't any better than the ones you have in the FT130 can here. And you have better endbell hardware.

Now, a 24 would be pushing it ! Grin.

Fate

[havlicek]

Hey John when I get abck I'll send you some mags to play with for these. I hope you got the labels. The clear one are in the plastic heat sealed paks. Looks great!

Hey thanks Barney. I'll give em a try for sure. I just got the labels in the mail today, and they really do look great. What I like about them (besides the sharp/clear printing) is how thin the material is. It seems no thicker than the thin foil labels Mura used...maybe thinner. The gold color looks very cool against this sorta Russkit-gold motor, so I'm going to stick one on this motor in honor of Team Cort

John, in the day when we were doing 27s as the upper limit, the ceramic magnets in our 16ds weren't any better than the ones you have in the FT130 can here. And you have better endbell hardware.

Now, a 24 would be pushing it ! Grin.

Good to know Rocky. I actually had my hand on a spool of #26 wire and then retreated at the last minute...not so much because I thought it would vaporize, but I'm hoping for a really strong (for it's size) motor that will also live a good life I'll definitely weld this com though, just to be sure...and if it seems like it has room to get a little wilder, I might try a second arm as a #26. (sometimes I just can't help myself)

-john

[havlicek]

Fresh outta the EZ Bake oven...a piping-hot #27 sgl. for my SCX monster project. Measures around .2+ ohms on my meter and draws 2.2 amps:


In it's new home with a quickie-setup:


How does it run you say? It freakin' screams like a banshee somewhere way up in G20 land or so Not bad if I do say so myself (and I do say so myself)...considering it started life as an $8 motor. The thing spins-up so fast, I think it actually could have been a #26...maybe even a #25 These SCX motors are a hoot!

-john

Note to Pablo: No fiber stack insulators were harmed in the making of this missle ...er I mean motor

[Prof. Fate]

Hi

John, you realize that it sounds like a Group 20 because a 20 IS a 27 wind?

Grin.

A local track allows zero glue, and keeps the track super clean and doesn't allow foam. But I got some time ran something interesting that would spin the tires all the way down the main 30' straight. And?

The locas said "whats the point, you cannot race it here and it wouldn't be drivable anyway". These guys just seem to be missing the fun of playing with power for its own sake!

Fate

[havlicek]

Hi

John, you realize that it sounds like a Group 20 because a 20 IS a 27 wind?

Grin.

Sure...but this one was made from an el-cheapo motor and still sounds that way. Point is...there's all kinds of possibilities out there for rewinding if a person were so inclined and these SCX motors are an excellent platform. Even with the stock endbell and com, you can get a heckuva lot out of these things. Good can, very good magnets, good arm that's EZ to rewind.

-john

[HarV Wallbanger III]

This looks great John and when I return I'll send ya a care pak and some silver labels as well to have another color.

[havlicek]

Hi Barney and thanks! These motors are very interesting, I suppose the vintage folks may see all this as heresy but I bet that the open fame/padlock people may have reacted to the Mabuchi can in much the same way. There's only so many nice old Muras, Mabuchis and Champions out there (and the parts to rebuild them), there's probably thousands...if not tens of thousands of these little guys and priced within reach of starving slot racers

-john

Oh and...I always look forward to those care packages of yours so thanks for that also!

[don.siegel]

All too true, John. I remember the old-line columnists referring disdainfully to the "tin cans" when they first came out, and you could just sense that they stayed attached to the solid Pittmans, probably a little longer than they should have (of course, a Pittman DC196-65X is not such a shabby beast...).

I was totally caught up in this whole attitude, even at 12 years old, and my first "real" purchase was an RP66 for 5 bucks, probably in 1964 (World's Fair in NY) instead of a whole kit for 6 bucks! That motor sat on my desk for a long time before I could afford the rest of the car...

Don

[havlicek]

...bingo Don BTW, all my brothers and sister worked at the Fair and I used my NYC bus pass as a kid to make many "unauthorized" visits there

-john

[don.siegel]

... .and that's where I tasted Saki for the first time, at the Japanese pavillion - kept me away from alcohol for the next 10 years! (but now I like the stuff - funny how tastes evolve from when you're 12...)

Don

[havlicek]

I just finished the last couple of details on the SCX RX42B motor. I trued-up the ends of the arm with an arm tool I just got. Unfortunately, the tool doesn't have much abrasive close to the shaft hole right where you really need it, so doing the tail-spacer didn't work very well. Even doing a tiny bit on the com end showed that it took off almost all the material around the edge of the com and very little tight to the shaft. Still after some effort I got it pretty good. I also tightened-up the endplay adding a fiber washer at the com and a really thin brass washer at the tail. After that I tried some different springs and the Camen regulars seemed to work best, adding some apparent RPMs and only increasing amp-draw very slightly. After a short break-in, the motor runs even better...a little smoother and seems considerably beyond even where it was at before (!?). The thing also seems to have a good amount of torque...spinning both up and down very quickly and with a noticeable "twist" in your hand as it does either (my unscientific measurement of torque). If you want to try or retry rewinding for little money and without risking a vintage motor, these SCX thingamabobs seem about as good as it gets, and you can take them as far as you want...really!



-john

[havlicek]

Along with refurbing some nice old motors for Maximo, I got one "special" project to do for him. He's calling this his "No-Holds-Barred" motor...I call it the "NHB" motor for short. This is to be a Mabuchi FT16D can/Champion endbell and it's my favorite kind of project because it's basically (within reason) one where whatever needs to be done to make this thing sing AND look purdy...will be done. It will be a soup-to-nuts job also involving a spffy "H" wound arm. here we go:

First order of business after laying out all the parts sent to me is to get the can stripped and to break off the endbell retainer tabs as well as the magnet stop tabs that also form the can-end ventilation holes. Here's the raw can ready for the next step:


Of course, any NHB motor worth it's salt is gonna have to have quality bearings on both ends, so while I'm at it, it's time to remove the caged bushing and ream-out the brass bushing boss for the 2mm x 6mm bearing to be installed. I've sorta perfected my system for installing these and have got it to the point where it's both easier to get a nice clean job, as well as a no-brainer that the bearing will be centered and lined-up well with the bore of the motor. Here's an exterior look with the brass carrier rough-polished as well:


...and here's a look inside where you can see how well the 6mm flanged bearing fills the space after soldering it in:


Next order of business is to flatten the magnet tabs and fill them in with solder (oldstyle body and fender work) After sanding down the solder, the next order of business is to do a thin/light "Bondo" job (new-style body and fender work) using some JB Weld to get some of the remaining imperfections out of that side of the can. After sanding it , working up to #220, eet looksa like-a dees (as my Italian Grandfather used to say):


OK, with only some grinding of where the endbell retainer tabs used to be and drilling the setup for screws before it gets painted, I can put aside the can for now and pay some attention to the endbell. We're using a lovely Champion 16D endbell for this project because, as nice as the Tradeship endbells are, the Champion is a couple of notches better. For one, it comes drilled already for better cooling and for two it has generous openings on the sides for the brush tubes...which we're going to need here Step one is to get a quality ball bearing installed on this end of the motor as well and, while I've detailed the steps involved in another post somewhere, I've also refined the sleeving process for this after seeing what works and what works better over time. The Champion endbell has a .25" bearing/bushing pocket and the 6mm bearing sorta fits inside .25" OD brass tubing after reaming it out a little. When tapping the bearing into the brass tubing, the tubing will swell or mushroom so it has to be ground back down to .25" afterwards to fit the endbell. If it's done carefully, the bearing and sleeve will be a nice tight "press-fit". Not so tight as to crack the endbell...but definitely tight-enough to not work it's way loose. Here it is installed:


...and here's an interior shot where you can see the brass sleeve around the bearing:


Now I just have to do a bit to the can and the new "H" arm will have a solid high-zoot setup to live in. The NHB motor is on the way

-john

[dc-65x]

Looking good John .

[Maximo]

Ditto! As Freddy Prinze would say "Loooking Goood!"

-Max

[Slotgeezer]

As usual, another Havicek masterpiece!

Now... will this get a Mabuchi-style blank, w/ the "thick" laminations? ... Or, an update to the new milenium & .007" lams?

I figure it'll get a Mura comm, eh?

Great work, as always, John... I dug thru the pile, & will get that "care package" in the postal shortly...

In the mean-time... ONWARD!!!!


Jeff Easterly

[havlicek]

Thanks for the looks guys. I just finished the paint and the can is in the Easy Bake^TM oven as we speak.

Jeff...I think I'm going to use a .007" arm for this one. I've gotta see what fits and, if need be whether I can push the shaft on one because most of my .007" arm blanks are set for can drive.

-john

[havlicek]

Can is done-dee-done-done I sprayed it with white appliance epoxy paint and baked it for 30 minutes (15 minutes/rest/15 minutes). The stuff is supposed to be a bit harder, moe durable and glossier and it seems to be. I really like the white on this motor with the white endbell...it looks retro and slick at the same time...I think ...kinda French Now that I have a setup, I can finish-off the endbell and then start messing with magnets and setting the arm length.



-john

[Pablo]

Very slick.. I love the new H stickers !

[Slotgeezer]

This is gonna be one NICE "French" motor!


Great job, John.... Enjoying this project a bunch!


Jeff Easterly

[havlicek]

Thanks Jeff Like I said, it's gonna be a "NHB" build so I'm giving it my best effort. I got the endbell pretty much built now. Installed 36D brush tubes/heatsinks with FT16D pentroof carriers. The whole setup pretty much drops right in to the the Champion endbell with only a slight amount of fiddling. Keeping the heatsinks to the outside to allow clearance for the fatter com has them sitting slightly tilted down towards the com end. What I do here sounds more dangerous than it really is as the Champion endbell material seems more heat-resistant than the Mabuchi auto-melt stuff I tin the inside of the carriers and the top of the brush tubes and then assemble them all slightly loosely (maybe a half-turn of the hardware screws or less). I then install an alignment tool with an arm shaft in the setup to be sure everything is sitting true and perpendicular to the motor bore. While holding the whole mess I simply reheat the hoods just until I see the solder re-flow and then "get out of Dodge" quickly. This slightly softens the endbell where the heatsinks touch it and besides getting the hoods soldered to the heatsinks, leaves everything "custom-fitted" to the endbell recesses. Soldering the hoods does at least two things I can think of.

1)It provides a solid current path in the event the motor needs one. Even with shunts installed, I'm guessing that a higher-current-draw motor may need more capacity than a pair of skinny shunts might provide. Maybe...maybe not, but at least that current path is there. I've seen older motors where they won't even run without the shunts making me believe that there's corrosion buildup over time between the hoods and brush tubes.

2)Should the endbell start to soften as the hardware heats-up under running conditions, the brush tubes won't start doing their imitation of "The China Syndrome"...melting their way down into the endbell towards the center of the earth If the solder joints fail, then there are bigger problems than can easily be addressed. Some sort of "super-proofer" setup is maybe a step even further towards bulletproofing, but the endbell starts looking more and more like a modern one with that kind of mod. Besides...I don't have one

Here's the endbell jigged and just soldered. I'll have to take it all apart and clean everything up before final assembly, but you can see how it all lines-up nicely with no additional machining of the parts.



-john