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Ken_Shea
11-20-2007, 10:22 PM
Any suggestions on disassembling this unit.
I need to do some machining on the shafts and body.
Could be it was not designed to be serviced only replaced, for sure there are alignment pins but I see no way of separating the two halves.

Thanks
Ken

http://i187.photobucket.com/albums/x175/Ken_Shea/TM16-E.jpg

dp
11-20-2007, 10:39 PM
It looks like you just need a pin spanner to unscrew the nuts holding the two shafts in. There may be nothing in there but grease. It looks like the worm gear and worm shaft pass through the holes and mate with no further assembly needed.

Carld
11-20-2007, 10:40 PM
Ken, not enough photo's. It looks like a parting line on the input shaft side all the way around. What is in the 6 holes on the side? Is there dowel pins in the four holes in the corners? Tell us more and more photo's please. There is no way they could get the gears in through the small bearing holes in the sides. It has to split open. It may have blind hole dowel pins holding it together and you may have to use a wedge to split it open.

It has to come apart, there is some way to open it.

Ken_Shea
11-20-2007, 11:04 PM
Dp, They just look like nuts in the picm they are actually seals.

CarlD,
Yes, that is a parting line, there were two center bolts, the four outer are thru bolts for mounting and additionally securing the two halfs I would suppose.

I do not see any dowell pins, only presumed they are on the inside.

Here is the pic of the back and opposite side.

http://i187.photobucket.com/albums/x175/Ken_Shea/TM16-E-a.jpg

Ken_Shea
11-20-2007, 11:27 PM
Carld,
The wedge suggestion is working, using a small chisel and it is coming apart.

dp, you lied to me, no grease, oil spilling out :D

Thanks for the help

Ken

dp
11-20-2007, 11:40 PM
Aack! I guess that means you'll need a new gasket, then :)

Ken_Shea
11-21-2007, 12:00 AM
No gasket Dp, this is a precision piece, or was :D

Any input on necessity of maintaining gear orientation ?


http://i187.photobucket.com/albums/x175/Ken_Shea/TM16-E-b.jpg

Carld
11-21-2007, 12:01 AM
Ken, I have a Snap-On scraper that looks like a putty knife that I use for jobs like that. It has a very sharp edge, as, if your not careful it will cut you sharp. It is flatened on the back now from me beating on it.

It works real good for seperating covers glued on with RTV silicone, etc.

Just what kind of lube is in it????

Locktite makes a sealer and there are others. Some of them are hard to detect on the surfaces.

My guess is it's set up to be reversed if needed. I don't think you'll have any trouble getting the gears in right.

My guess is you'll have to make some pins to align the bolt holes the reassemble the gear box.

Ken_Shea
11-21-2007, 12:15 AM
There was some form of silicone sealer, the lube smells like differential lube but somewhat thinner.

I liked the scraper idea, though little damage was done with the small chisel.

I marked the gears best I could but I am with you on the doubtful need.

I think the the bearing races will provide all the alignment needed, what's your opinion on that?

OK, that was the easy part, not to remove the bearings to machine the shafts to a diameter I can use for attaching a motor and 4" chuck.

Thanks again

MGREEN
11-21-2007, 12:16 AM
[QUOTE=Ken_Shea]


Yes, that is a parting line, there were two center bolts,

I do not see any dowell pins, only presumed they are on the inside.

Ken,
The center bolts holes are blind holes and are threaded in the rear
half only correct?
If so, then try a piece of plate steel running from top to bottom,
mark out for a smaller hole at the center bolt, top hole,
and bottom hole.
Thread in a socket head cap screw in the center hole long enough
to fill the threads and have the head flush with the front face of
the casting.

Fit in lead expansion shields in the upper and lower holes ONLY
in the front half.

Drill a hole in the center hole mark in the steel plate just big
enough to get an allen wrench through the plate.
Drill holes for lag screws in the upper and lower holes.

Attach steel plates with lags into the lead shields, tighten down,
insert allen wrench through small center hole into the cap screws
and turn counter clockwise to try to back the cap screws out.
The cap screw threads will jack the rear half away hopefully.

Couldn't hurt to sand or grind away the hammerite paint all
around the seam line.
This seams like a softish approach to me.
Mike Green

MGREEN
11-21-2007, 12:21 AM
There was some form of silicone sealer, the lube smells like differential lube but somewhat thinner.

I liked the scraper idea, though little damage was done with the small chisel.

I marked the gears best I could but I am with you on the doubtful need.

I think the the bearing races will provide all the alignment needed, what's your opinion on that?

OK, that was the easy part, not to remove the bearings to machine the shafts to a diameter I can use for attaching a motor and 4" chuck.

Thanks again

Guess I'm too late, you already got it apart!

Ken_Shea
11-21-2007, 12:27 AM
Thanks Mike,
Yes a bit late but a useful method none the less.

Ken

Carld
11-21-2007, 11:32 AM
Ken, I think the snap rings on the brearings will align the gears correctly. You could remove the bearings with a puller or in a press if you need the clearance to turn the shaft. Just be sure to wash the bearings real good but I'm sure you know that. I have turned worm gear shafts between centers with the bearings so you'll have no problem.

What always jerked my rope was hidden or overlooked bolts when taking something apart :eek: and the damage that results.

wierdscience
11-21-2007, 08:37 PM
Be sure and refill with synthetic gear lube made for bronze gear reducers.Dinosaur puke contains large amounts of chlorine based additives that eat bronze.

Ken_Shea
11-22-2007, 08:36 PM
wierdscience, thanks for the lube tip, I would not have guessed that.