# Grizzly G8689 Mini-Mill



## MattM (Nov 10, 2012)

I broke both the nylon transmission gears in my mini-mill.

Problem is I can't figure out how to remove the spindle assembly so I can replace the gears.  I have removed everything down to the two large bearings and am now at a standstill.  I have the schematic but still can't figure it out.  The only thing I can think is the whole assembly is a press fit.  However I hesitate to start pounding on the spindle without knowing for sure.

Help.


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## OakRidgeGuy (Nov 10, 2012)

While you have that machine apart, may i suggest you give it this lil upgrade.

http://www.littlemachineshop.com/products/product_view.php?ProductID=2560&category=


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## hq308 (Nov 10, 2012)

The spindle should come out fairly easily, from memory I don't think it's a press fit. Oakridgeguy is on the money, forget about the gears and buy or build yourself a belt conversion. Your mill will be MUCH quieter and considerably smoother and you won't have to worry about breaking any more gears. 

I broke 2 sets of plastic gears and then made the mistake of replacing them with metal gears which are even louder :yikes:

The belt drive conversion is the best thing I ever did.


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## MattM (Nov 10, 2012)

Thanks to all.  I ordered the belt drive kit.

  Do I have to disassemble the head to get the wrecked gears out or can I just leave them?


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## hq308 (Nov 11, 2012)

You can leave the gears in, put the high low selector 1/2 way between high and low, then remove the handle. That's what I've done with mine. The only small annoying issue is occasionally it will vibrate into gear and the gear train gets a little noisy but a quick tweak of the selector sorts that out.

Edit. Because the gears are broken it's probably better to remove the head and take out the gear that moves on the selector . You can leave the gear on the spindle, just remove any broken pieces.


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## MattM (Nov 11, 2012)

I removed the shaft that the selector gear was on.  How about if I just leave it out?  The spindle turns freely and noiselessly without it.  I can see parts of the broken gear in the box.

At the end of this exercise I will have a shaft with a keyway, a key, and two sealed bearings to use in some other project.


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## hq308 (Nov 12, 2012)

You might get away with it but I'd be concerned about broken bits of gear getting caught in the remains of the spindle gear. Being plastic gears I guess it can't really do any real damage. Probably the worst it could do is jam up the spindle although I thinks even that's unlikely.:thinking:


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