Source of Maxon/Faulhaber 4:1 Gearheads

[Kentuckian]

Thanks for the sacrifice, Max!

[glakedylan]

thanks Max for the reply. so, it would seem i was not just confused but not realizing two separate parts
that usually will not come together and the need to find each separately.


i get it now. thanks. i appreciate the explanation which answers all my questions.


with gratitude
Gary

[mmagliaro]

A happy ending on the "sacrificial motor" story.
I was able to machine back the rest of the 1024 face, removing all the threaded nose.  I cut off the chewed-up part of the motor shaft where the pinion was, leaving me with a decent length of un-mangled 1mm output shaft.   All that curring back also cut away the entire front bearing.  But I was able to turn a little piece of Delrin rod, bored out for 1mm, to stand in as a new front bearing and press it into the can.  Amazingly, the motor tolerated all this "brutish" experimentation, and it now runs beautifully again.  Of course, there's no putting a gearhead on it ever again because the threaded front is gone, but it's a perfectly good dual-shaft 10x24 coreless motor.  Maybe I'll have a use for it one day.  At least it didn't end up in the waste basket.
--------
This made me very curious about using Delrin sleeving as a bearing in motors instead of the usual bronze bearings.  I know plastic motor bearings are used commercially, and these motor shafts have such little load on them, relatively speaking, that I bet Delrin would last forever and be an oil-free and "squeal free" part.  Notice how Kato abandoned the bronze worm bearings in their locos years ago and started using all-plastic bearing blocks.  I wonder if they came to the same conclusion.  I always thought it was a cost-saving measure, but maybe it wasn't.

To that end, I turned a Delrin front bearing for one of my experimental Rivarossi motors and it seems to work perfectly.   

[metalworkertom]

Another fun fact about these 10x24 motors I found on the bay...   they have an encoder on the back, which is not useful to us.  But if you carefully pry and cut it away from the back of the motor, you can get rid of it to save all that wasted length.  More importantly, on these particular versions, there seems to be a real bearing and a steel shaft on the back for the encoder.  In the past, I have only ever seen them with a plastic shaft and a weak bearing that cannot support any real load.  But these could be used as double-shaft motors!

I have some 1016 Faulhaber with the same steel "Rear" shaft. Will have to look about the bearing but I think it is on them too.

[Kentuckian]

Got my motor, gearhead, and encoder in the mail today.

Yes, the gear head does fit the 10x17 motor. @mmagliaro, any tips on how to remove the plastic metal piece on the shaft without ruining the gearhead? So far I have just tried pulling, and no luck. Now we just have to wait for the pinion gears to come in.



Also, how to remove the encoder from the donor motor? I twisted the cover off by hand, but can’t get “the guts” to move.



Thanks.

[mmagliaro]

That metal thing on the gearhead output shaft is held on by a metric set screw set into one side.  If you don't have an allen wrench to match, you just have to drill it out.  I even HAVE metric set screws, but I could not get that thing to budge, so I ended up just clamping that assembly on the end of the shaft in a small vise and gently drilling out the set screw with a 1/16" drill bit.  I did it under my milling machine, and if you have a drill press, with a vise you can clamp the piece in (not the motor, just the thing on the end of the shaft) that will make this much easier.  But you could still just clamp in a vise and use a hand drill if you have to.   Alternatively, I suppose you could cut right into the set screw with a Dremel cut off disk.

As for the encoder assembly on the back - you can't remove that easily.  it's all glued permanently in place.  I just gingerly slice away at it with  Dremel disk until it's all gone except the two motor terminals coming out the back of the motor.  If you accidentally slice off the motor terminals, don't panic.  Sometimes that happens.  It will still leave a "nub" in the plastic rear of the motor.  Just put some flux on the nub, tin it with solder, and then solder a nice piece of fine stranded wire to it.  It will work fine.

Here's one of the two I just received, where I did get a little too aggressive and sliced the motor terminals clean off the back.  I just tinned and soldered right to the nubs.



Also, that silver colored washer you see on the back shaft in this photo is something I added.  You will just see a red plastic one.   This is the motor that I completely machined-off the front nose and had to make a new front bearing on.  Since I destroyed the nose, there was nothing keeping the armature shaft in place, laterally, in the can, so it could pull too far forward and the little red plastic bushing on the back shaft wasn't going to stop it.  So I added a stainless 1mm washer, shown here, with some red loctite on it, to keep everything in place.  This is definitely an "experimental motor" that has already lived a very hard life, but in the name of science, it was worth it.  At least it runs!

[Kentuckian]

I thought I would have to drill in out. I never would have figured out the encoder without ruining the motor, I’m sure. Thanks for letting me benefit from your experience.

[mike_lawyer]

Max -

I have a couple of 6 volt Faulhaber 1016s with the pinion for Faulhaber gearheads.  Just so I understand, the Maxon gearheads won't be a simple screw on to the motor, but require a Maxon pinion?  Maybe I got that backward, but wanted to clarify.  Thanks!

[mmagliaro]

Max -

I have a couple of 6 volt Faulhaber 1016s with the pinion for Faulhaber gearheads.  Just so I understand, the Maxon gearheads won't be a simple screw on to the motor, but require a Maxon pinion?  Maybe I got that backward, but wanted to clarify.  Thanks!

You have it backwards.  The Maxon 10mm gearheads DO fit on the Faulhaber 1016.  I just tried this with the metal-gear Maxon gearheads we are talking about (that I just got off eBay) on a Faulhaber 1016.    The Faulhaber pinions fit because they are just slightly smaller profile teeth than the Maxon.  I detect a bit more noise, but I don't think you'll care.  And yes, they screw right on.
I also tried this with the plastic-geared Maxon gearheads.  They also work, but not as well.  There is more gear noise and the motor won't start up at sub-1-volt levels like these usually can.  You'd have to judge if it's good enough for you.  I don't think it is damaging the teeth.  There is just a bit of mismatch between the plastic gear profile and the metal one.

Here's the recent Maxon metal gearhead on my 1016.  Works like a charm.  Starts up at around 0.6 volt.

[mike_lawyer]

Thanks Max for the clarification, much appreciated!  I have two Faulhaber 1016s with the pinion on them, waiting for gearheads, so it is nice to know this is an option.  I do have some 10/1 gearheads at higher gear reduction ratios (like 64:1), but I need to summon the courage to try and cut them down.

[mmagliaro]

Here's the follow-up on the pinion gears, as promised.  The brass pinions I got from eBay came today.

They fit the Maxon shaft perfectly and mate into the gearhead perfectly.  The motor runs smooth as silk - better than with the plastic pinion I was using.  All I had to do was run some sandpaper against the running motor shaft for a minute or so to take it down just a hair, so that I could slip-fit the pinion on.  You can't "press" the pinions on these motors, because the fit is kind of tight, and I didn't feel at all safe putting pressure on it.   If you have a 1mm drill bit, you could use that.  I did ream it out with a #61 bit, which is close, but it still wasn't quite enough.  I test-drilled a #60 hole in some metal, but that's a little too big and might be sloppy for a gear fit.   It would have to be a 1mm drill.

So if you don't have a 1mm drill bit, just buzz the motor shaft with sandpaper, slip the gear on with a drop of Loctite.

You can still find these on pinions eBay, searching for "0.2m 12T gear", but they have really dried up since I ordered mine.  There are still a few on there.  Otherwise, just be patient and check around the web periodically.  Little brass pinions in mod 0.2 come up all the time.  Just make sure you get mod 0.2 and 12 teeth with a 1.0mm bore.

Back to removing the pinion on that 1024 motor...
I'm afraid it's a lost cause.  Ain't no way it comes off without destroying the gear.  That thing seems to be fully welded to the shaft.  I machined back the case so I could get a gear pulled behind it, and no way will that thing budge.  Then, chewing away at it with a Dremel (I decided that this motor and gear would be a sacrificial lamb), I found that the gear NEVER releases from the shaft.  It is fused to it all the way through and all the way down.

But all is not lost!  As it turns out, these pinions are not the tiny mod 0.8 or other crazy size that I've seen on some Faulhabers.  I measured it.  It is a 12 tooth, mod 0.2 with a 1mm bore.  That is not too hard to find.  Start digging on eBay or at surplus places on line
for "mod 0.2 gear" and see if you can find one.  That's what I'm going to do.  The other option is to get the custom made ones I order from that place in Poland, but before we resort to that, I want to see if there is just a bunch of cheapies on eBay.

UPDATE... that was easier than I thought.  Just search for  "0.2m 12T gear"
I have a batch coming from China as we speak.  It will be a couple of weeks or more before they show up here, but I will see if they work as Maxon pinions.

[woodone]

Max, have you tried a reamer- that will make a much cleaner ID on bore. Drills tend to be hard to control because of the twist lead.
Also on removing the gear. Are you trying to save the gear? Or just remove it so you can use a different gear.
For removal I would try to grind the face of the gear until the weld can’t be seen by your eye- then heat up the gear to expand -if luckily the gear should just slide off. Maybe I am not following the need here.

[Kentuckian]

I’m glad to hear everything went well!

My pinions arrived last week. I’m three weeks into a rotator cuff shoulder surgery recovery and still have my right (dominate) arm in a sling. So I am going to wait a few more weeks before I try to put the motor, pinion, and gear case together.

Still have to decide which loco will be the recipient . . .

[mmagliaro]

Max, have you tried a reamer- that will make a much cleaner ID on bore. Drills tend to be hard to control because of the twist lead.
Also on removing the gear. Are you trying to save the gear? Or just remove it so you can use a different gear.
For removal I would try to grind the face of the gear until the weld can’t be seen by your eye- then heat up the gear to expand -if luckily the gear should just slide off. Maybe I am not following the need here.

I don't have a straight "chucking" reamer the correct size.  I have a 1.5mm, but not a 1.0mm, otherwise I would have used it.
I have some jeweler's reamers, but they are tapered, so no good there.

Yes, if you happen to have a 1.0mm chucking reamer, or any type that isn't tapered, that would be ideal compared to a drill bit.  I just didn't assume anybody would have one.

As for the weld, on Faulhabers, what you described works perfectly.  You can buzz off the face, until you hit the weld and then the gear slips right off.  But on that Maxon, that never happened.  I ground it down and ground it down and it was still tight.  I think they must have used a locking compound, but I didn't try applying heat, since it would probably destroy the motor.

[woodone]

For heating up the gear I was not thinking of a flame to heat. I was thinking of using a soldering tool to apply the heat to the gear only.
A large tipped high watt one so I could get a lot of heat on the gear quickly.
There are some readers on E-Bay for a fair price.
When I started doing motor replacements I got two or three of the readers from 1MM to 4MM to make bushings and such.
But I am tool poor. LOL