4 way tool holder

[Millwright1009]

With qctp being so expensive I had a short piece of 5” stock. Decided to make a general 4 way post. The lantern style with This is missing the bottom washer. It’s a pain to use, plus it’s not very rigid. Great way to get some practice anyways. I’ll post the finished product.

When I’m done it should be around 3.25” square. This is a 12” lathe with 1.5 “ to centre, I have .625 left on the bottom with ability to hold a 7/8 tool. Which is one of the bigger homemade ones I have.

I’m justifying this project, I had the stock there, plus the experience for me with this machine wouldn’t hurt.

The biggest problem I have is parting. I have tried a few different approaches. Best I’ve found is a rounded tip, and cutting atleast 2x wider. Diving in about a 16th before it chatters then doing the same next to the first cut. Chips are rolling away, and look good. But it will eventually chatter.

 

[Millwright1009]

 

[phaxtris]

Thats a long ways to stick out that skinny parting blade, I imagine that's part of your chatter problem

If you haven't already parted it off entirely have you thought about parting only a half inch or so and hacking the rest off with a band saw and then just facing off the mess

 

[Millwright1009]

I didn’t have it out this far the whole time. Even out 1/4” is giving almost the same results. Checking centre height after each adjustment. Slightly over centre seems to be best. I drilled 1” or so out, parted most of the way and cut the rest off with a chop saw. Im in need of a band saw lol.

 

[Millwright1009]

Thats a long ways to stick out that skinny parting blade, I imagine that's part of your chatter problem

If you haven't already parted it off entirely have you thought about parting only a half inch or so and hacking the rest off with a band saw and then just facing off the mess

lol, spoiled when working. All the tools needed are there, when I’m home I have nothing to work with it seems like.

 

[phaxtris]

Ha wow that's a long ways to cut with a chop saw, fighting the blade glazing up the whole time I can imagine, but you made it !

I'm not a parting expert, I don't really like doing it, probabaly because I'm somewhat impatient and parting feels like it takes forever l. That being said I never had much luck parting with a lantern tool post, it would not always but quite often chatter as well, if everything is locked down that could also be part of the problem

 

[Millwright1009]

Do you mean like using a carriage stop?

 

[phaxtris]

Do you mean like using a carriage stop?

You should be able to lock the carriage down, there should be a bolt (probabaly a square headed bolt on for you) that will tighten a clamp onto the bottom of the ways locking the carriage on place, and if you can tighten up the compound or at least put it at a 90 to the cross slide and just use the cross slide that should reduce the amount of deflection in you setup as best as you can and that's all you can do with a lantern post

 

[Millwright1009]

You should be able to lock the carriage down, there should be a bolt (probabaly a square headed bolt on for you) that will tighten a clamp onto the bottom of the ways locking the carriage on place, and if you can tighten up the compound or at least put it at a 90 to the cross slide and just use the cross slide that should reduce the amount of deflection in you setup as best as you can and that's all you can do with a lantern post

The compound is at 90°, this is an old Harrison lathe, the carriage lock is apparently an extra, which isn’t on it. Something else I’ve been meaning to do. In saying that I have a dial installed on the back of the carriage to measure movement. I’m sure the lock would help tho that’s for sure

 

[phaxtris]

If you can figure out some way to lock the carriage it will definitely make a difference

 

[whydontu]

can you engage the half nut but disengage the saddle feed? So the saddle is connected to the lead screw but the screw isn’t turning?

 

[Millwright1009]

can you engage the half nut but disengage the saddle feed? So the saddle is connected to the lead screw but the screw isn’t turning?

I tried that last time I was parting and it didn’t stop the chatter. Never thought about it last night tho

 

[phaxtris]

I tried that last time I was parting and it didn’t stop the chatter. Never thought about it last night tho

I believe that's because locking the half nut will help with side to side, but the carriage can still *rock* perpendicular to the ways....rock is kind of a dramatic term, but you get the meaning

 

[Millwright1009]

I believe that's because locking the half nut will help with side to side, but the carriage can still *rock* perpendicular to the ways....rock is kind of a dramatic term, but you get the meaning

Yes I see what you mean. After this is done I’m going to fab up the rest of the taper attachment. It has the right lead screw and the rotating block on the back. All is missing is the parallel on the back to lock the taper and the bracket that holds it. Somebody must have taken it off and never stayed with the lathe

 

[phaxtris]

Yes I see what you mean. After this is done I’m going to fab up the rest of the taper attachment. It has the right lead screw and the rotating block on the back. All is missing is the parallel on the back to lock the taper and the bracket that holds it. Somebody must have taken it off and never stayed with the lathe

Crazy that it had a taper attachment but not a caridge lock, but sweet either way, easier to make a caridge lock than find a lead screw/block

 

[Millwright1009]

Crazy that it had a taper attachment but not a caridge lock, but sweet either way, easier to make a caridge lock than find a lead screw/block

Cross slide and carriage stops are separate from what I can tell in the old diagrams.
As for the taper attachment I only have half of it. But the hard part to make I already have which would be the proper cross slide assembly.

 

[phaxtris]

What I meant was that the original owner sprang for the taper attachment but not the strangely optional but definitely cheaper carriage lock, that's like ordering a car with power windows but manual locks

 

[Millwright1009]

I wouldn’t doubt this was decked out with all the options. It came from an Ontario school I believe. But I bought it out of a guys basement. Not sure how long he had it. Somebody must have took part of the taper attachment or when it was sold it was taken off and was never kept with the lathe. Same with change gears. I’m sure it came with more for doing metric threads but the guy never had any. They’re a 14 pitch gear so they’re hard to find.

 

[Dabbler]

You can buy 14 pitch gears online, but surprisingly made-to-order gears seem to be cheaper somehow. About 8 years ago we went down this road with a friend, and got his gears reasonably. I'm sure there are more options now.

on the parting I didn't see what your spindle speed was, forgive me if I skipped over it somehow. one half of the equation is making everything more rigid. the other half is reduce pressure by lowering RPM and using the sharpest possible cutter.

One trick that made parting FAR easier was to move the blade slightly below the centre line. On my 12" lathe for 1" cutoffs, was .002 - .003 below centre.

 

[Millwright1009]

You can buy 14 pitch gears online, but surprisingly made-to-order gears seem to be cheaper somehow. About 8 years ago we went down this road with a friend, and got his gears reasonably. I'm sure there are more options now.

on the parting I didn't see what your spindle speed was, forgive me if I skipped over it somehow. one half of the equation is making everything more rigid. the other half is reduce pressure by lowering RPM and using the sharpest possible cutter.

One trick that made parting FAR easier was to move the blade slightly below the centre line. On my 12" lathe for 1" cutoffs, was .002 - .003 below centre.

100 rpm was my speed according to the chart at the top. But the actual rpm isn’t known. I can’t tell the motor rpm because there is no badge. But one speed up at 150 seemed fast and I think 64 was the next down which seemed to slow.