# G4003g / Shopfox M1112g Qcgb Lubrication



## Superburban (Oct 29, 2016)

I put this here, because the G4003G lathes may have the same issue.

My Shopfox M1112G (built and used since 2011), has been getting noisier lately. Today I got a chance to dig into it. I opened up the QCGB, and found it completely dry. There is nothing getting oil inside the QCGB. I should have taken pics, but did not have my phone with me.

On the right side, I found there is a cover that has the two oil ports, the top on leads to a port on the QCGB, and then drips straight down to the two output gears, it looked to be working, but only affected the two gears.

The lower port should have led to another port on the QCGB, but the cover was not cut flat, so the inside of the port, did not touch the side of the QCGB, so the oil just went straight down the outside of the QCGB. Nothing was making it to the inside of the QCGB. It took a bit on the belt sander to get the inside of the cover flat.

The right side cover is easy to remove, to see if yours has the same condition.

My poor diagrams, attempt to show the way the oil should go (red line), but with the inside not being flat, the oil just dripped down the inside (Blue lines)





Besides taking a look at the right cover, I would suggest removing the front cover, to examine the gears.


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## Superburban (Oct 29, 2016)

The Left side, I found the oil port goes to the gear shaft, but since there is a rib (Not sure if thats the right name), the oil is only going to the left side of the shaft, and again, nothing is going into the QCGB. Where I indicated in red (I covered up the rib/ridge built into the shaft), the right side of the shaft was dry, and of course has noticeable play in the shaft. I can also feel slop in the two gears, (2318 & 2320).

Also, the two selector shafts and the gears inside were all fairly dry, with noticeable play in the gears on the selector shafts.


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## Superburban (Oct 29, 2016)

I'm going to order all the bearings, and bushings, then take the QCGB apart, and see what can be done. Likely make oversize shafts for the gears. I also want to rig up a better way to ensure the assembly gets oil, sort of a one shot lube system.

I recommend anyone with any lathe with a similar QCGB, either use a mirror, or remove the front cover, and take a look.


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## Superburban (Oct 29, 2016)

I also found the two sealed bearings inside the step gear (86 & 91 tooth gear), were spinning inside the gear. One just fell out, the other took a light push. The inside of the gear, and outside of the bearings showed lots of wear. I'm also getting new bearings, and will locktite them, and hope that holds.


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## mmcmdl (Oct 30, 2016)

I now have a Woodstock International , Shop Fox M1112 12 x 36 gunsmithing lathe residing in my garage . I swapped my 17 x 60 lathe for it . Could any body use it as I don't need it .


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## rgray (Oct 30, 2016)

I never trusted those oil holes. The top one will take all the oil you can put to it and the bottom takes one squirt and will take no more. I also removed that right cover to see it the lower was blocked.
I got in the habit of spraying chain lube on them (hillbilly one shot system).


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## Superburban (Oct 30, 2016)

Here is the inside of the cover, the boss in the center is where the lower hole is. On mine, it was about 1/8" lower then the edge, leaving a gap and preventing the oil from migrating into the inside of the QCGB. The second pic shows the side of the QCGB and the two oil holes.


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## Superburban (Oct 30, 2016)

rgray said:


> I never trusted those oil holes. The top one will take all the oil you can put to it and the bottom takes one squirt and will take no more. I also removed that right cover to see it the lower was blocked.
> I got in the habit of spraying chain lube on them (hillbilly one shot system).



The top one seems to go into a chamber above the QCGB, I looked, but can't find where it goes from there, I guess it will have to wait until I pull the gear box. With the side cover off, filling the oil hole, just leaks out the two top bolt holes.

The lower hole goes to one of the shafts, so two drops a day should be plenty for it, but thats all it oils.

I like the chain lube idea, but have to wonder if it would be too thick to work its way into the shafts.


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## Superburban (Oct 30, 2016)

Here is the left side, you can see the input shaft, and the thrust ring built into it. The second pic is the cover, you can see the oil hole is on the outboard side of the ring, and no oil makes its way to the inside. I think the key here is to oil the heck out of it, while pulling on the gear, and hope oil makes its way inside. This shaft is where I have lots of play.


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## mksj (Oct 30, 2016)

I had issue with my Norton gearbox not getting oil to all the gears/holes, it didn't seem to matter how much oil you put in on one end, it  didn't make it to the other end and all the oil drip holes. I would initially would spray oil up into the gears from underneath. A number of us have added pump oilers with a manifold to distribute the oil, this can either be done with small oil tubes from a distribution block or drilling a manifold block with oil passage ways to drip the oil in the appropriate spots. I still periodically oil the outer bearings, but the pump oiler system gets all the gears and shafts wet with two pumps. 
http://www.hobby-machinist.com/threads/pm1340gt-gearbox-pump-oiler-system.37284/


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## Superburban (Oct 31, 2016)

Thats the same thing I have been thinking of. Thanks for the posting & pics.


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## civdiv99 (Nov 21, 2016)

rgray said:


> I never trusted those oil holes. The top one will take all the oil you can put to it and the bottom takes one squirt and will take no more. I also removed that right cover to see it the lower was blocked.
> I got in the habit of spraying chain lube on them (hillbilly one shot system).


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