[QuinnSjoblom]

Ordered a used draw tube on ebay. Doesn't fit in my spindle bore. My spindle bore is about 1.377, maybe few tenths over that. The drawtube varies between 1.378 and 1.379. I kind of assumed most 5c draw tubes should have the same general clearance, but apparently not. I would try another used on ebay, but not sure what's gonna fit. This one didn't have a brand name listed. Is it odd for a draw tube to be a few thou over 1 3/8? Or is it my spindle thats odd and they are usually bored more than 2 thou over 1 3/8?

[Jim Dawson]

I would expect a 1 3/8 spindle bore to be about 0.010 or more over. I would just turn down the OD of the drawtube a bit, maybe take 0.010 or so off of it. It sounds like the draw tube is made of stock size tubing which can run a bit out of round and oversize or undersize a bit.

[deadlykitten]

hello quin, even a new tube may get poligonal ( deformated ) in time, at values >0.03mm, under normal exploitation conditions

about clearence, this may be a few tens of a mm, like 0.3 - 0.5 at least ... of course, depends on spindle construction

also, considering that spindle bore is 80H7, and the drawtube is 79.5h7, this does not mean that you have 0.5 clearance ... you may have 0.5±0.15, depending on the play&orientation with the threads inside the spindle and inside the hydra-cilinder

like jim said, if it's bigger, you may machine it to make it smaller / kindly

[QuinnSjoblom]

Ok, thanks guys. Unfortunately I don't have a functional lathe to turn this down. The mill turn spindle im building would do a fine job of turning down this draw tube, but it won't be functional until it has a draw tube. It relies on 5c for all work holding. Once it has a draw tube, I can put a 3 or 4 jaw 5c chuck in it. so you can see the dilemma.
So my options are either finding someone to turn down this tube for me, or buy the dunham draw tube meant for it, or try another used one on ebay. The dunham tube will be about 250 shipped. EBay has tubes all over for MUCH cheaper, just don't know what's gonna fit. I guess what I'm asking is if most draw tubes are gonna be like this one, or if some are smaller and will fit directly in my 1.377 bore. I guess I can start sending messages to eBay sellers and ask them to put calipers on their tube.

[Jim Dawson]

If you were close to me I would turn it down for you for $20 (or lunch, I work for food. ) I'm sure there is someone near you that has a lathe in their garage, put an ad on your local Craigslist in the gigs section. I do jobs like this for local hobbyists every now & again.

[QuinnSjoblom]

If you were close to me I would turn it down for you for $20 (or lunch, I work for food. ) I'm sure there is someone near you that has a lathe in their garage, put an ad on your local Craigslist in the gigs section. I do jobs like this for local hobbyists every now & again.

Thanks, I'll give it a shot and see who I can find