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- Feb 26, 2014
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- 258
I have a Tripan 211 model and can confirm mine does hold .001" or less.
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QCTP repeatability
- Thread starter martik777
- Start date
I have a Tripan 211 model and can confirm mine does hold .001" or less.
- Joined
- Jan 31, 2016
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No in a nutshell .
I make a lot of small parts where I swap the cut off tool, RH tool & diamond over and over again. I use the dial indicator for position on cross slide and get about .001 repeatability. I set the compound at 6 degrees and measure the part and use the compound to get within a couple of tenths.
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- Jul 29, 2014
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Aloris literature claims repeatability of half a tenth, 0.00005. I have an Aloris CXA tool post, with an assortment of various tool holders, Aloris included. There are numerous Youtubers showing tests, so maybe there is some data to review, but I just know I have never seen repeatability errors detectable in actual use. Not that I would notice a 50 microinch error.
I do notice that my tool post causes the holder to rise about 0.002” as the wedge is tightening. This makes me question their spec, as the torque could be a bit of a variable for each closing.
I do notice that my tool post causes the holder to rise about 0.002” as the wedge is tightening. This makes me question their spec, as the torque could be a bit of a variable for each closing.
Are you saying that you use the dial indicator to check position after each tool change? Import tool post? wedge or piston?
- Joined
- Apr 23, 2013
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- 1,014
I don’t think it makes sense to worry about how many tens of a thousand the tool repeats in a home shop. Even when I was doing close work on a CNC when I changed to a new fresh insert edge I would offset the dia make a cut , then adjust the offset dia too correct size.
I had guys say I only use TPG inserts because they are made more precise than TPU inserts. I thought why not take a test cut then adjust too size needed. And use the same grade insert that was less costly.
Old school guys never worried about how close they set the tools when they put a tool in a lantern toolpost.
I had guys say I only use TPG inserts because they are made more precise than TPU inserts. I thought why not take a test cut then adjust too size needed. And use the same grade insert that was less costly.
Old school guys never worried about how close they set the tools when they put a tool in a lantern toolpost.
I have a self made quick change toolpost. I have measured the repeatabilty on the small lathe. I get (3S) 0.02 mm in turning diameter (outer turning). That means that in 99% of the tool changes, the turned diameter is withing 0.02 mm, a bit less than 0.001".
To achieve that, the 4 way tool post is locked. It can't be rotated any more. All tools are shimmed at the bottom to set the tool heigt, at the back to position them under the bolts and on the top so I only have to losen the 2 locking bolt half a turn. At the back of the tool there is a small stop to position (stickout) the tool always the same way. After a few months I replaced the the 2 bolts by a single handle locking system.
How can a locked 4 way post be quick change? Photos?
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- Oct 11, 2016
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I have an Aloris BXA wedge. Vertical repeatability is +/- .001 Horizontal is about the same.
My piston offshore AXA with offshore holders repeats +/- .002 horizontal and +/- .001 vertical.
You can see it here:
My piston offshore AXA with offshore holders repeats +/- .002 horizontal and +/- .001 vertical.
Dorian makes an Aloris - type tool post with 4 holding positions, so it is both 4-way *and* quick change.
You can see it here: