How to Install a Quick Change Tool Post on a South Bend Lathe

In this video I will be going over the installation for fitting a quick change tool post to my lathe. A big shout out to Precision Matthews for sending out this tool post, this is their AXA quick change tool post set. It includes a straight holder, straight with a V groove, boring bar holder, knurling holder, and parting bit holder. #precisionmatthews #machining #southbend
Wedge Quick Change Tool Post Set, AXA Size: www.precisionmatthews.com/sho...
To fit this attachment to my lathe, I must make a t-nut so it can fasten to the tool post slide. This kit comes supplied with a base plate that is already threaded to the center bolt, it doesn’t however need to be machined to match your lathe. Considering this is a square piece, I installed the 4 jaw chuck.
I’m centering up the threaded hole, this is needed so the t-nut fits correctly in the slot. I installed the threaded stud for the tool post and then used a dial indicator. You’ll need to work with 2 jaws at a time, the ones across from each other. Zeroing the indicator may be helpful but isn’t necessary. Take a reading at the edge jaw, whichever is facing the dial indicator. As an example. If one jaw has a reading of 0.000” and the other is 0.040”, you’ll need to divide the difference. The higher numbered jaw must move in 0.020” while the lower numbered jaw will have to move out 0.020”. It’s important to not over tighten the jaws so you’re now marring the edges of the part. It may take a bit to work between all 4 jaws, as you get more used to this it’ll become easier.
When done, I’m within 0.001” which I’m happy with.
Now we’re onto cutting the piece. The piece is 0.500” thick and will need to be cut down 0.220”, leaving the bottom portion 0.280” thick.
I got down so far until I found that the jaws would interfere with cutting the piece down any further. I switched over to the 3 jaw chuck, threaded it onto the center threaded stud and used the supplied nut to lock the base plate in place.
The raised portion around the threaded hole remains the full height, the overall thickness of the t-nut should be slightly shallower than the tool post slot on the lathe. We don’t want any interference when tightening down the tool post. If it’s too high, it can prevent this and not allow the tool post to lock into place properly.
The diameter of the raised center portion is 0.870”. I’ll provide rough drawings towards the end of the video specific to my lathe.
Here is a quick test fit to ensure it’s correct so far. I was noticing a rougher finish with my hss cutting bits, these all had a positive rack. I ground a new cutting bit, this time switching to a negative rack which made a huge improvement on my cuts.
Switching back to the 4 jaw chuck, the t-nut now needs to be cut to width. The total width of the t-nut is 1.280, the raised portion with the threaded hole will need to be centered. So the lower portion will need to be a total of 0.205” on each side. Quite a bit needs to be cut off so it can be rough cut with a band saw or cut off wheel to save a bit of time if you wish.
I am working with one side at a time so the piece is kept square on the headstock side. The piece is then deburred using a file. This will remove any sharp edges or corners. 320 emery cloth is used to go over those deburred edges.
My lantern style tool post is then removed and the new t nut can be installed. Thread in the center stud, it’ll stop threading at the shank which prevents the stud from going through fully where it risks damaging the slot’s surface. Install the quick change tool post.
Thread on the retaining nut. Install the handle, and tighten it with a wrench. Then the knob for the handle.
After that one of the attachments can be installed, this one is the straight holder which has a 1/4” to 1/2” capacity. I have a bunch of carbide cutting bits that came with my lathe, finally I’m able to use them. The bit can be centered using the tailstock dead center and the height adjustment nut is locked into place always saving the position. It’ll be fast and easy to switch between tool bits.
Welcome to my channel, Matt's Metalworking. Please don't forget to hit that LIKE button and SUBSCRIBE for future videos. My name is Matt and I produce metalworking relating videos which can include fabrication, machining, milling, turning, welding, tool tutorials, etc.

[@bradnail99]

I need to do this to the tee nut for my new QC tool post. Was thinking I had to use a milling machine (which I don’t have) but now I see I can do this on my lathe, which is wonderful news! The lathe I recently received is a Sheldon 11 by 44 from 1946, and the lantern style tool post is its chief weakness.

[@narcisoracoma6621]

Im considering a quick change tool post! I like the fact that you did all the milling on a lathe! I don't have a mill , but I do have a milling attachment for my 9" south bend, i wonder i could still do a t-nut? I do have milling bits but no collets yet.. lol

[@civedm]

Wow. Would not have thought to cut the t-nut as done in this video. Now i know how to make mine. Thanks.

[@mrskunk697]

Exactly what I needed to see thanks.

[@MattsMetalworking]

You're welcome!

[@lavonmarshal3127]

instructions unclear now my lathe is on fire.