I have used a 4 way for years, but changed to QCTP. – I now rarely use the 4 way. The QCTP is more expensive and when you buy it, you need to buy some extra holders as its a devil to get holders that fit the QCTP several years down the line.

If a supplier says T37, order that on the proviso that if it doesn't fit, you can return / exchange for a different one / money back.

Bob

I have a myford size Dickson on my WM250 and it's just the right size.

If I was starting from scratch, I would go with the wedge type, mainly because it's easier to build tools(like a powered spindle, slotting tool etc) that fit directly onto the post.

A Myford size is ok for a Boxford 4 1/2 in lathe (9in swing) if you pack up the block 3/16" but for a 10" lathe I would suggest a Boxford sized one despite all the holders then being more expensive, And as suggested above the wedge type rather than piston or Dickson is the current best option.

+1 for nothing wrong with a good old 4 way, you can even have interchangeable 4way blocks.

Edited By Bazyle on 09/08/2022 18:49:56

Thing to be sure of is the size of the QCTP allows it to be fitted to the saddle and then that any tool put in it can be adjusted to centre height. In other words don't fit a giant tool-post to a tiny lathe or vice versa! Journeyman's website may be helpful.

I don't recommend option 4! Swapping the whole tool-post would be pretty clumsy I think. It's easier to pre-shim tools to height and swap them as needed. I've thought of super-gluing the correct shims to all my carbide insert holders but decided it's not worth the effort. A QCTP advantage is HSS tools can be resharpened and reset to height in the cartridge very quickly : tools in a 4-way have to be removed and then re-shimmed because sharpening can move the tip. ,

Depends on what the lathe is used for, but I decided against a QCTP, partly because I mostly use carbide inserts, where the tip position doesn't move when an insert is changed. Tool changing on a 4-way doesn't take long enough to annoy me and QCTPs cost a fair whack of money that I preferred to spend on other toys. Putting a DRO on the lathe for example. Or buying metal quickly before the prices go up again!

I rarely put more than two tools in my 4-way because sticky-out tools in all positions often get in the way or create a medieval weapon system for spiking unwary hands. However, I find the 4-way a good compromise and it has the advantage of being stiffer than a QCTP, not that QCTP owners admit to having floppy tools. Perhaps they're too embarrassed!

Dave

A QCTP is good for HSS, otherwise a matched set of insert holders give only one shim to make for all three in the existing 4 way. The speed advantage is therefore irrelevant and the height adjustment for HSS is the only thing left worth having.

don't like my QCTP. tool holder tends to work loose in heavy cuts and the whole thing moves around the center fixing post . only use it for light work now and drilled a hole opposite the tool fixing positions to fit a locating pin [ drops into the tee slot the tool post fixes to ]

They have their uses, particularly for users of hss tooling, as there should not be any bother with shimming after every sharpening to get on centre height. We have avoided QCTP's at the museum, all our tooling is indexable, holders are milled down to centre height, or boxed with custom made shims for smaller boring bars. Having a choice of over 50 tools would be rather expensive and space consuming if QCTP's were used.