# 3 1/2' Heavy 10 Lead Screw length?



## Don T (Jun 15, 2020)

Okay I am trying to put my heavy 10 back together. Now from my research I have an odd ball QCGB that is shorter than others. So my heavy 10 has a 3 1/2' bed. Would anyone here know the total length that the lead screw is supposed to be? Mine is about 37 1/4". I am basically trying to find out all the things I need to get this working again. I also need the gear and nut that attaches to the end of the lead screw. The person that had it before me was trying something weird and had the lead screw attached directly to the shaft that comes out through the banjo gear mount. He used a threaded spacer to attache the lead screw to it and the gear that should be on it is gone and he was trying to drive it with a sprocket! Any help would be great. Thanks


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## Cooter Brown (Jun 15, 2020)

That gear box is missing way to much to rebuild it.....


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## Don T (Jun 15, 2020)

Cooter Brown said:


> That gear box is missing way to much to rebuild it.....


Yes I know that is why I am asking about lead screw length. I want to buy another QCGB but mine is an add ball short one not seen on but a few lathes. So I am trying to find out if I need a lead screw also.


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## Cooter Brown (Jun 15, 2020)

the screw looks right... just make sure its 3/4" 8 threads per inch.....


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## Don T (Jun 16, 2020)

Cooter Brown said:


> the screw looks right... just make sure its 3/4" 8 threads per inch.....


The screw is the one that came with mine so yes it is correct for what I have. But Like I said mine has a shorter than normal QCGB and I can't find a replacement like it. So I am looking at buying one of the longer QCGB's. So I really need to know how long the lead screw is on other peoples 3 1/2' SB's so I can make sure I don't need to buy a lead screw as well.


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## Cooter Brown (Jun 16, 2020)

I made a print for my lead screw when I thought I was going to make a new one for my H10 with a 3 1/2' bed..... about 39.25"oal..... This is for the big gearbox.


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## Don T (Jun 16, 2020)

Cooter Brown said:


> I made a print for my lead screw when I thought I was going to make a new one for my H10 with a 3 1/2' bed..... about 39.25"oal..... This is for the big gearbox.
> View attachment 327807


Wow that is not what I was expecting! I was thinking that mine would be longer than others because my gearbox is actually shorter. Mine is definitely 37 1/4" long. so now I am a bit baffled? What year is yours? Thanks


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## Cooter Brown (Jun 16, 2020)

Don T said:


> Wow that is not what I was expecting! I was thinking that mine would be longer than others because my gearbox is actually shorter. Mine is definitely 37 1/4" long. so now I am a bit baffled? What year is yours? Thanks



My machine is a 1938 heavy 9 with a 3ft bed and I cut down a leadscrew I got on ebay to fit my machine..... But when I made the print I added 7.5" because I was going to make one for a friend.... I had to cut down the length about 7.5 inches for my 3ft bed......


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