QTCP debate

I started production machining in 1953 . That is 69 years ago. My NEW Logan 11 inch turret lathe had a 4 way tool post and a production cross slide with a tool post on the rear. There was no digital read outs in those days. There were 6 stations on the turret. Many times all 6 stations had tools loaded and the 4 way and rear tools were used. It was hard to keep track of all the grease marks on the
lathe dial. What mark went to what tool.
When guick change tool posts became common I was in heaven. I think I have used most styles of qctp and don’t prefer one over the other.
 
Chances are I'll just have one tool block and just replace tools in it often, except QTCP don't make this easy so you really are forced into having to have one tool block for every tool..
I don't see why you think changing tools in QTCP tool block/holder is harder than changing them in a 4-way. I keep the appropriate size hex key on my lathe to loosen three set screws and drop in a new tool, then adjust the height. About the same amount of work without having to keep a stack of shims handy. Of course unless you have more than 4 tool holders/blocks, there isn't much advantage over the 4-way.
 
This is one advantage to a QCTP. Reach over and grab the tool you want and be cutting in 30 seconds. This collection has taken many years but it is a very small cost in the big picture.
I would guess the average cost is about $13 each. Just not very long ago you could purchase these BXA holders for $40 for 4 of them. They are about doubled now.
Joe
 

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Chances are I'll just have one tool block and just replace tools in it often, except QTCP don't make this easy so you really are forced into having to have one tool block for every tool... it just seems to get expensive.
The entire point of a QCTP is to have each tool mounted in it’s own tool block. If you are not going to do that, then you should stay with what you have.

I would get the best quality tool post you could afford, but tool blocks are easy enough to make if buying them is too expensive. You could use a longer piece of material to make the dovetail for multiple blocks in one shot, then cut to length and finish each block. Or you could order extra blocks from China, that is not something that really needs to be a name brand. I have a no name tool post set, but plan on getting a Dorian tool post for my lathe at some point, but will continue using my existing Chinese tool blocks since they should still fit.
 
I also can't figure out why you think it's easier to change a tool in a 4-way versus a QCTP. You can have as many (or as few) toolholders as you want, but just having your common tools in their own toolholders, and then a spare toolholder or two for swapping tools you don't regularly use is a very workable solution. I have 52 tool holders (just counted 'em yesterday) - that's pretty much one for everything - and I consider it a great investment. But, as I said before, if a 4-way works well for you, there's no point in spending more money.

GsT
 
From what you're saying, I don't have any doubt that you'd enjoy a quick change tool post of any description. If height adjustment is your biggest headache, I'd say the same thing I did when you were asking a similar question this summer. I think you should look into a DIY Norman style tool post. They are kind of their own thing, not a quick change, not a lantern/rocker, not a four way without significant effort (although you could more than likely make a very nice three way post out of it, reserving the fourth side for the locking bolt). I think that would do what you are looking for. There's any number of examples of them posted here, and all over the internet. You need not use an existing design, you can make it as you wish. Crude but effective (as mine is), all the way up to very fancy and refined. The first holder you make will take forever while you figure it out, after that they're really not too difficult. You'd (probably) have to buy in the bolt and set screws, but the entire thing, start to finish, can be made with very simple tools. You'd need an end mill, two taps and tap wrench, a hack saw, a drill, and a few drill bits, and your lathe. The lathe will do the bulk of the work. It's daunting when you first look at it, but each step is pretty simple.

If you do decide to buy in a quick change tool post, The Aloris style will be the easiest (or equal) to get mounted and set up, and offer you all of the adjustability that you are looking for. The Multifix will be somewhat more involved to set up (probably, not necessarily), it won't offer you any more positions or positionability. What the multifix offers is more "preset" positions available without rotating the tool post. In practice, the difference between moving the tool holder to a new position, or rotating the tool post is only where you put your hand when you loosen it. If I was going to go that route (I'm not at this time, but if I was going to), I'd probably pony up for the wedge style, not the plunger style on the post it's self, at which point the tool holders can be bought in as needed, they're fairly easy to make IF you have a mill, or dirt cheap to buy, they come in all kinds of configurations for different tools. I just don't have enough predictable work to make any tangible time or effort gains from the fixed angular adjustments of the Multifix types. That takes production line work before you'll ever get ahead for having that feature.

You said you found packs of shims just for this purpose- You said you don't mind swapping tools in the four way tool post you currently have- Would it solve the issue for you if you just super glued the correct amount of shims under your current tool bits, so that each tool bit was already correctly shimmed, every time?
 
The QCTP, wedge type, that came on my Chinese PM lathe has been fine for hobby work. @ about $15 for tool holders, BAX, I keep a row of them with tools mounted and on center. A typical turning project requires several tool changes in quick succession. Each tool change takes maybe 15 seconds. My time is sort of valuable, I'm running out of it.
 
When I make a part I often use a tool for a long turn, then another for turning to a shoulder. When I cut off I cut part way thru then switch to a chamfer tool to do the end of the part and also chamfer into the cut off groove so the part will be chamfered on both ends. Then back to cutoff to finish the cut. Shimming tools would drive me crazy (er)!
 
Given the variety of tooling I have and use, I would absolutely go NUTS without a QCTP. I'll second the notion of investing in a quality Aloris or Dorian QC tool post, and buy individual import tool holders at $15 each.

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The adjustability of the Multifix tools post is only a functional benefit if you are replacing the compound with a solid tool post plinth and giving up the ability to rotate the QCTP. The benefits of increased rigidity far outweigh the the disadvantages of having a fixed QCTP position. I have not found the fixed position QCTP an issue with the solid tool post plinth and only switch over to the compound when turing tapers.

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Given the variety of tooling I have and use, I would absolutely go NUTS without a QCTP. I'll second the notion of investing in a quality Aloris or Dorian QC tool post, and buy individual import tool holders at $15 each.

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The adjustability of the Multifix tools post is only a functional benefit if you are replacing the compound with a solid tool post plinth and giving up the ability to rotate the QCTP. The benefits of increased rigidity far outweigh the the disadvantages of having a fixed QCTP position. I have not found the fixed position QCTP an issue with the solid tool post plinth and only switch over to the compound when turing tapers.

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Well, if I win the lottery then I'll spring for a quick change tool post. I simply don't have the money now... or rather I got rent, electricity, etc. to pay before I can have leftover for this. I doubt I'll ever buy some American made tool post. Logistics make this impossible, not to mention shipping would cost about 3x the cost of the tool post itself. I think I'll take my chances with chinese copies.
 
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