Source of Maxon/Faulhaber 4:1 Gearheads

[mmagliaro]

There have been some posts here by people looking for 4:1 gearheads for their Maxon or Faulhaber motors.
Well, here's a possible way to go if you cannot find one.  Hunt out Maxon 320555 or 388941 motors on eBay (or anywhere else, for that matter).
The 320555 and 388941 look like a proprietary product combination (as most surplus Maxons are marked) for a 10mm diam 24mm long motor with a 4:1 gearhead on it.  BE SURE YOU SEE A PHOTO since people mis-mark their eBay ads all the time and might say "320555" when it's not.  The motor in the picture will clearly have the number on it (388941 or 320555).   It will also be obvious that the motor has a gearhead in the photo.

You should be able to get that gearhead to fit other 10mm Maxons that have a threaded nose.  You may have to be adept at gear pulling and delicate work to do this, but it can be done.  These can also be adapted to a Faulhaber 10mm motor (our dear departed friend, Eldon Shirey, used to do this).  They will screw on the Faulhaber 10mm motors, but the pinions won't match, so you need to be able to adapt a Faulhaber pinion gear onto the Maxon shaft, which requires DRILLING OUT the Faulhaber stainless gear to a larger size, and doing it VERY precisely.
I didn't say it was easy.  It's just something you might want to try if you reall need a 4:1 gearhead and can't find them.  A number of these motors with the gearheads are floating around just now, so I thought I'd mention it to the group.

[Kentuckian]

Would the gearhead fit this motor?

[mmagliaro]

I   *think*  so... that's one of the 10 x 17 right?   Of course, the rub is that you will have to get the pinion off the other motor and put it on that one.  I have some 1024 with gearheads I've gotten off eBay, and I have some of the 1017's.  I will try it and let you know.  I'll be surprised if it doesn't fit.

[mmagliaro]

Okay, the short answer is "probably yes".  I tried some plastic and metal Maxon gearheads off of 1024 Maxon motors and yes, they do fit the 1017.  The catch is that you need the right pinion for your 1017.  I had some spare gears lying around, so I just put one on my 1017.  But getting the one off the 1024 looks tough.  It is set so close to the motor body that no gear puller I have can get behind it so I can pull it off.  I am pretty sure they are just pressed on (not spot-welded on like the Faulhaber pinions!).  And don't even think about just trying to "pry it off with a screwdriver".   I suppose if one were willing to sacrifice the whole 1024 motor, you could chop away at the motor body until you get the shaft out, and then pull the gear off with a puller.

The motors I'm seeing on eBay right now look like they have the metal Maxon gearheads (which are nicer than the plastic ones - less friction and noise - even though the plastic ones are no piece of crap).

I bought a couple of these 1024's with the gearheads... so when they arrive, I'll try all this out and let you know how it goes switching the gearhead to a 1017.

[Kentuckian]

Thanks!

[mike_lawyer]

Thanks Max for the heads up!  Very interested to see if the gearhead works with the 1017.

[metalworkertom]

Something else I need to look at when I get caught up from being on Vacation.

[mmagliaro]

Something else I need to look at when I get caught up from being on Vacation.

Yeah, Tom, one big thing to check out are the way some Maxon gearheads can fit on a Faulhaber motor.  The reverse is not true.  Faulhaber gearheads won't go on a Maxon. 

Here's why.
Some Faulhabers and Maxons share the same pinion, EXCEPT that the Faulhaber gears have a slightly lower profile.  The gear itself has the same modulus (something like 0.8, I bet) but the teeth aren't quite as tall.  The Faulhaber motor and pinion will fit into the Maxon gearhead and the mesh works quite well.  But if you try the opposite, even if the pinion teeth are the same modulus, they don't fit because the Maxon pinion teeth are too tall.

Of course, if you just put the right pinion on the motor to match the gearhead, it will always work, IF you can thread the gearhead onto the motor, from either brand.  Some of them will screw on, cross-brand, and some won't.  Eldon had done a lot of tinkering with this, keeping track of which ones fit where, but I don't have that information.

When I was playing with them tonight, I found that the Faulhaber 10/1 gearheads will fit on some 10mm Maxons, but not on others, due to different nose threads.

[mmagliaro]

The two I bought came today.  Yes, they definitely fit on the Maxon 1017.  And these are seriously good Maxon gearheads - the ones with the metal cases and stainless gears.  The ones that turn so smoothly that when you turn the output shaft in your fingers, it feels like you are turning nothing but air.  You can't even feel the gears move.

The trick will be to get yourself a pinion for the 1017 that matches.  I happened to have one.  The one that is mounted on the motor that you'll get would work, of course, IF you can get it off the other motor without destroying it.  I'll try that tomorrow.  There is a "melty" metal mass on the end of it that looks like it make been somehow welded.  I'll see how it goes with a gear puller.

[Kentuckian]

Thanks for the experiments, Max. I have one on the way. I’m curious to see how to remove the pinion.

[mmagliaro]

I looked at this today.  I do not see any way of prying that pinion off there without destroying the 1024 motor that comes with it.  It is far too close to the housing to get any kind of gear puller behind it, and it really on there firmly.  You won't be able to just pull it off with your fingers.  I had another Maxon 10mm gearhead that I cannibalized years ago, and saved some of the little planetary gears out of it.  Those work perfectly as a pinion for this, so that's what I put on my 1017 to test it.

So unless you've got another gearhead or pinion lying around, this won't be easy.  I hate the idea of destroying a whole motor just to get the pinion off, but that might be necessary.  What I'm thinking is that I could tear the motor apart, get the shaft/basket assembly out and then I'd have plenty of room to put it in a gear puller, or even just hang it in a strong V plate between the jaws of a vise and gently punch the shaft out of the gear.

I'll play with it some more tonight and see if I can figure out how to get that pinion off.

This is one of those sad, poignant times when I think to myself, "I wish Eldon were still with us.  He would know how to do this."

[glakedylan]

i will note this under a heading of "i probably do not know what i am doing"


everytime i search for Maxon or Faulhaber motors, i never find any that
(1) will fit in N Scale locomotive
(2) have a gear head with anything close to 4:1 nor a separate gear head to add to a motor and have it still fit
(3) motors that are rated at 12V (rather than 3v or 6v)


my understanding is that if you want really slow operations and slow starts the motor gear head match
is what is noted in this thread. (thanks Max...your info is always helpful and appreciated).


i do not know if i am not using the correct terminology in search
or that they are so scarce they are really difficult to find


the one i keep returning to in eBay search is so long i doubt it would fit (in length) most applications
or this that for just using the motor and finding a much shorter gear head to fit?


confused, as is normal for me.


sincerely
Gary

[mmagliaro]

i will note this under a heading of "i probably do not know what i am doing"


everytime i search for Maxon or Faulhaber motors, i never find any that
(1) will fit in N Scale locomotive
(2) have a gear head with anything close to 4:1 nor a separate gear head to add to a motor and have it still fit
(3) motors that are rated at 12V (rather than 3v or 6v)


my understanding is that if you want really slow operations and slow starts the motor gear head match
is what is noted in this thread. (thanks Max...your info is always helpful and appreciated).


i do not know if i am not using the correct terminology in search
or that they are so scarce they are really difficult to find


the one i keep returning to in eBay search is so long i doubt it would fit (in length) most applications
or this that for just using the motor and finding a much shorter gear head to fit?


confused, as is normal for me.


sincerely
Gary

Gary,
It's because the ideal combination we want in N Scale is an 8mm or 10mm diameter motor with a 4:1 gearhead and those almost NEVER come up ready-made on ebay.  So your options are:
a) give up
b) find the 8 or 10mm motor, no matter what gearhead it has on it, or even if it has none at all, and then start hunting
for the 4:1 gearhead on something else that you can make work.

... OR
Use the 10mm (or 13mm if you have room) motor all by itself with no gearhead.  It won't have the "miraculous" slow-speed
running that I'm always after, but it will still be the most powerful motor you can possibly find in that size.  You can usually sleeve the output shafts to make them work with a 1.5mm bore worm, or use the NWSL U-joint adapters in cases where you have to join the motor to a worm that rides in its own independent bearings. 

As for size... there are always plenty of 10mm, 8mm, and 13mm Maxon or Faulhaber motors floating around.
And no, you don't have to obsess over them being "12v" motors.  A 6v Maxon or Faulhaber can tolerate being driver up to at least
10 volts under heavy load without damage and this gives you a much broader speed range than a conventional motor has.  It's not the voltage that kills motors - it's the current and the heat.  If the motor if wound such that under heavy load it still doesn't draw too much current to destroy itself at well over its "rated" voltage, it does just fine.  Personally, I prefer the 6v motors when I use the 4:1 gearheads because that gives me ultra-slow speed and ALSO decent top speed.

[mmagliaro]

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.

[mmagliaro]

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!