Removing a metal worm gear off a marklin 3-pole armature?

[VonRyan]

Hi all, on Thursday a much anticipated package came in from the UK containing some all-important parts for about 1 1/5 Z scale loco(s) the brunt of which is a second version chassis to a marklin v60. All that it is made up of is the metal frame, three geared axles with wheels and the side rods attached to the outer two wheels/axles, plus the highly important worm gear, but one problem... the worm gear is attached to the useless three-pole armature and i need the gear to put on new motor shaft that i can use to link with a piece of flexible tubing that'll link the worm gear to a 12v 6mm X 12mm motor. Now what makes this problem worse is that the worm gear was put on after the motor armature was put through its hole in the metal chassis, thus linking the three, leaving only ~1.5mm of gear exposed.

As is i plan to modify the frame so as to make it into the basis of an Nn3 0-4-0 with a Welsh design. The modifications i plan to make however, require the armature being out of the way, and the modifications will not enable the gear-armature combo to be removed.

I've tried to pull the worm gear off the armature with my finger nails, but no budging what-so-ever. I cannot damage the gear any little bit or i risk ruining the all important fine-mesh between the worm gear and the axle gear.

If anyone has any suggestions, comments, ideas, etc., i'd much appreciate it if you could share them.

Also, if anyone can offer any sources, ideas, suggestions of what and how and where to get small diameter, flexible tubing to make the 90-degree link between the to-be horizontally mounted motor to link the vertical shaft for the worm gear.

When all is said and done this should enable me to have a motor in the boiler of the locomotive and the motor/worm-gear-shaft linkage in the firebox, thus creating a fully open cab to allow for some aesthetic additions, i.e. brake, regulator, fireman, driver, and the all important coal. (which i'm still working on finding a proper source)

Thanks all!

-Cody F.

[Chris333]

If that chassis was in my hands I would simply break all of the motor armature off the shaft. Once the shaft is bare it will fall out the bottom of the chassis. Once out you can mount it on a plate or loose in a vise and tap the shaft out with a old drill bit smaller than 1mm.

Also there is a bushing in the frame above the worm. The other bushing is at the top of the motor. If you link the motor shaft and the worm shaft with tubing it will leave the worm to flop around a bit. I would mount the worm right to the new motor shaft.

[Chris333]

Just re-read.  Yeah there is no way you are going to bend 90 degrees like that. If you want the motor in the boiler you will need to do something like this:

http://www.exact-messebau.de/minilok/detail89/Dsc00507.jpg
http://www.exact-messebau.de/minilok/V20_Bilder/Faulhaber1.jpg

It involves using another gear.

[VonRyan]

Hmm, that may or may not work since there is limited space in the planned fire-box. plus it looks like their motors are mounted way too high for what i'm planning on doing.
The boiler is planned to be only about 8mm wide and not much longer than the motor perhaps 22mm at the very most, thus space is going to be at a premium.

To eliminate the possible wobble, i intend to use the planned new-shaft for the worm gear to go through the worm gear and into a hole in a styrene pre-cover plate that'll have the actual brass cover-plate over it.

I've seen the tubing method used before for right angle applications, but only in pictures and once in person. Only problem is that i don't know what, where, who, and how to get it.

-Cody F.

[DKS]

I wonder if the worm is not so tight that you couldn't mount the motor firmly in a vice and, using a broken drill bit, drive the shaft through the worm and the motor armature with some very light tapping. (The motor will be ruined but so what.) Another thought would be to destroy the motor utterly by using a Dremel cutoff disc to slice right through the side of the motor just below the armature. From there you may be able to free the shaft and simply pull the worm and shaft out the bottom. (I confess that, without photos, this may all be quite useless.)

[VonRyan]

I wonder if the worm is not so tight that you couldn't mount the motor firmly in a vice and, using a broken drill bit, drive the shaft through the worm and the motor armature with some very light tapping. (The motor will be ruined but so what.) Another thought would be to destroy the motor utterly by using a Dremel cutoff disc to slice right through the side of the motor just below the armature. From there you may be able to free the shaft and simply pull the worm and shaft out the bottom. (I confess that, without photos, this may all be quite useless.)

Some of that might work, i'll have to see if i've a broken drill bit around that is small enough since i don't own a "small" drill-bit set, probably anything i have is over 1mm in diameter, but i might have some steel wire that might be small enough.

-Cody F.

[Chris333]

Half way down the page:
http://www.zscale.org/articles/fivepole.html

[VonRyan]

Half way down the page:
http://www.zscale.org/articles/fivepole.html

Is there a cheaper option in terms of gear pullers, perhaps one that is no more than $6? (literally all that i have left)
I like the fact that it has fingers to hold the gear/chassis.

-Cody F.

[Philip H]

You might check Harbor Freight Tools, but it there's not one close then shipping could put you over.

[Chris333]

I don't have that gear puller. I have a small one, but it won't fit on this chassis. Like I said if it was mine I would just remove the motor by breaking up the armature. Crush it with pliars and keep going till it all falls off. Maybe some of it would need to be ground away, but in the end you have the worm and a long shaft. You can trim the shaft to what you need and never even have to pull the worm.


Sorry, but I still don't thing your tubing will work. I've never seen it done any way other than straight. You could try 2 bevel gears:
http://www.gizmoszone.com/shopping/agora.cgi?product=Other_gear;ppinc=1a

If you order from them you may be interested in some 1mm shafts:
http://www.gizmoszone.com/shopping/agora.cgi?product=Axles;ppinc=1a

If you replaced the chassis bushing with a short piece of brass or copper tube that would support the worm shaft. Like this, but shorter:
https://picasaweb.google.com/ErieChris333/Nn3#5598960134071287954
https://picasaweb.google.com/ErieChris333/Nn3#5599815433321977746

[VonRyan]

I don't have that gear puller. I have a small one, but it won't fit on this chassis. Like I said if it was mine I would just remove the motor by breaking up the armature. Crush it with pliars and keep going till it all falls off. Maybe some of it would need to be ground away, but in the end you have the worm and a long shaft. You can trim the shaft to what you need and never even have to pull the worm.


Sorry, but I still don't thing your tubing will work. I've never seen it done any way other than straight. You could try 2 bevel gears:
http://www.gizmoszone.com/shopping/agora.cgi?product=Other_gear;ppinc=1a

If you order from them you may be interested in some 1mm shafts:
http://www.gizmoszone.com/shopping/agora.cgi?product=Axles;ppinc=1a

If you replaced the chassis bushing with a short piece of brass or copper tube that would support the worm shaft. Like this, but shorter:
https://picasaweb.google.com/ErieChris333/Nn3#5598960134071287954
https://picasaweb.google.com/ErieChris333/Nn3#5599815433321977746

Those bevel gears look quite enticing. I'd have to fit some brass tubing in them to have a smaller bore for the 1mm shaft and the .7mm shaft on the motor. Those might actually be a better option that using flexible silicon surgical-tubing.

I just went ahead and bought one of their 1mm axles and a pair of the bevel gears.

-Cody F.