QCTP holder

Follow up question. Wedge type or piston type? Pros and cons?
 
The action of the Wedge QCTP's Locks the Tool Holder both against the height adjuster (downward pressure) and against the dove tails (outward pressure). IMO Better.

The Piston Style applies only outward pressure against the dove tails, and you have to trust the tool holder is seated against it height adjuster.

Both styles use the same holders, so the only savings is with the initial purchase of the tool post.
 
If you want to save some money, look at the sets for sale at CDCO and at All Industrial Tools. Compare the delivered prices there with the ones on eBay, and go for it. Import tool posts and holders are not necessarily of consistent quality, but the low pricing makes it worth the gamble. Return for exchange or refund anything you do not like.
 
I find the BXA fits my 12 inch lathe perfectly, but to be safe you really need to measure. Ilke that the BXA is bigger, therefore stronger more rigid. I've not tried the piston type, but it does appear that they would not be as good as the wedge type.

I bought a genuine Aloris with a few tool holders, plus some non genuine holders, but I've not yet had the opportunity to compare them. The non genuine are softer in a file test, and the finish is a bit rougher, especially the threads, but then they are cheaper, so time will tell.
 
I ordered the BXA last night from CDCO plus the indexable turning tool set. Looking forward to trying it on my first turns with this lathe. Thanks to jbolt for his very helpful research and everyone who responded here for helping me make the decision.
 
It is of course now too late to back out as you've bought a BXA, but in my opinion you would have been better off buying a better quality AXA rather than the BXA that you bought. You are going to find in the future that virtually all tooling is going to be more expensive for little or no performance improvement.

On the subject of wedge versus piston, piston type performance varies directly with the size of the piston and with the piston shape where it contacts the holder. The Chinese-built units that I have seen photos of all use a smaller circular contact shape. The first foreign QCTP competitor to Aloris was, I think, Yuasa in Japan. I bought their full AXA set when I bought my 3996 38 years ago (and as I recall, paid more numerically than you just paid for the CDCO). And both are still working fine. The piston contact shape is rectangular and significantly larger than the circular Chinese ones. However, today the price difference between Chinese made piston and wedge sets is negligible, and still cheaper than the few used Yuasa's that I have seen on eBay. So the wedge type is the better choice.

On another subject that is independent of all of the above, you should as soon as you can afford them buy several more #1 (201) and/or #2 (202) holders. All of the sets that I have ever seen only come with one of each. With only one, the only advantage that a QCTP has over the 4-way Turret is that the vertical adjustment is more convenient. The first job that you run that requires two or more cutters that have to be mounted in the #1 holder, you are going to be back to having to get out the Allen wrenches and then adjusting the height every time that you need to change cutters. I currently have about a dozen #101's (201's for you), most with a cutter already mounted and adjusted.
 
I ordered the BXA last night from CDCO plus the indexable turning tool set. Looking forward to trying it on my first turns with this lathe. Thanks to jbolt for his very helpful research and everyone who responded here for helping me make the decision.

First of all did you get the wedge type? It just works better than the piston ones. Second the tool holder set you purchased is the T style or the CCMT style? I prefer the C style of inserts because with one holder you can face and turn without changing holders. Also the inserts fit the corresponding boring bars that saves you inventory of inserts to have on hand


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wa5cab, at first I did order the AXA but I decided to change that for a couple reasons. First, I wanted to be able to adjust the height of the holder as little as possible to get the cutter centered with the chuck. The BXA will hold stronger 1/2" shank cutters so I will only have to adjust height about 1/8" up. Second, the person I took lathe and mill classes from stressed setting up for the least amount of deflection. I thought the BXA did both of these things slightly better than the AXA for a very small cost difference.

jdedmon91, I got the wedge type. For the cutters, they use the triangular T style inserts. In my lathe class the cutter used T style I think and we faced and turned with the same setup.
 
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In my experience there is no difference between piston and wedge toolposts, at the level of precision anybody reading this should be worried about.
 
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