Lathe solid tool post mount thoughts

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dml66

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I'd like to try a solid tool post mount on my 7x10 instead of having the tool post mounted on the compound.

My first problem is I don't own a mill so I'd have no way to square up a mount, nor accurately make it's height the same as the compound.

I've searched the internet to see if anyone sells such a beast, haven't found anything yet.

Then I got to thinking, what if I bought a compound bottom and top, then bolted them together into a monolithic assembly. There'd really be no need for a gib, nor gib screws, just a few holes drilled and tapped in the bottom, and corresponding holes drilled in the top, less than $100 in parts.

Thoughts?
 
What tool post are you putting on it? Does it have to be square?

I did mine a little different, I made a Norman tool post for my compound, and a similar, larger one for use directly on the cross slide. Essentially a plinth that takes tool holders directly, instead of adding a tool post on top of a "block". Round works just fine for me.

If it'd work for you, if your tool post could bolt to it, round is easy. If you've got a four jaw chuck, you could certainly face a square block to length. The only critical dimensions are the height and the parallelism of the top and the bottom.
 
Jake M said:
What tool post are you putting on it? Does it have to be square?

I did mine a little different, I made a Norman tool post for my compound, and a similar, larger one for use directly on the cross slide. Essentially a plinth that takes tool holders directly, instead of adding a tool post on top of a "block". Round works just fine for me.

If it'd work for you, if your tool post could bolt to it, round is easy. If you've got a four jaw chuck, you could certainly face a square block to length. The only critical dimensions are the height and the parallelism of the top and the bottom.
Click to expand...

I'm used to QCTP, probably keep it that way for the time being.

I thought about a round solid mount, the only problem I see is getting the two flat sides parallel. The QCTP inscribes a roughly 2.5" diameter circle which is manageable for turning and facing on a 7x10, however, once the faced part is removed from the chuck, rotated and re-chucked to face the other end, all bets are off for parallelism. Maybe if I turn the part and face it using the 4-jaw independent, then flip it and indicate the 4-jaw near the about-to-be-faced end, that'll be good enough for parallelism. I have to confess I've never tried that.
 
I also made a norman style QCTP for my lathe. Easy but time consuming to make the holders. The only truly critical dimension is that the ID of the hole in the tool holders has to be within a .001 or two of the OD of the post to be easy to clamp the holder to the post. The top of the post does not have to be parallel to the bottom. The post probably doesn't even have to be perpendicular to the base. But that is easy to do on the lathe.

When I made mine I made the post about 2" longer then it needed to be. Parted off the extra and use it to test fit the hole.

www.hobby-machinist.com

Norman Style QCTP

I have been using my Norman style QCTP and have sorted out the problems that came up through use. Instead of placing my findings at the end of the very long thread on making it I thought that it would be better to put everything in one place. First off you have to measure the distance from the...
www.hobby-machinist.com www.hobby-machinist.com
 
You have a 4-jaw so you can make square-ish blocks by facing- piece of cake
One of the many benefits of 4-jaw chucks
What kind of dimensions are you looking at?
 
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What’s wrong with buying a rectangular block of metal?
 
This is one I made up recently. It's a copy of Mikes, but I just extended the base to be longer. I added very basic indexing with a spring plunger
 

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Jimsehr said:
What’s wrong with buying a rectangular block of metal?
Click to expand...
The problem is finding a piece of metal with the correct dimensions. The height of the block in particular measures 1.583", that's impossible to find. The width and depth are less critical; 2" square should do it. I have thought about using a piece of 2"x1.5" rectangular bar, while it would be nice to have 1.583", the 0.083" height difference could be accounted for with the QCTP.
 
I'll give the 4-jaw with square stock a shot, I'll try it on some scrap to see how it goes.
 
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