Tangential tool holder for QCTP

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Shawn

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I have wanted to try one of these tool holders for awhile now but only finally got around to building one. Definitely worth the effort to build, cuts great and you can turn and face without changing tools or angles.

image.jpg

Shawn
 
Looks great. Any plans or drawings available ?
 
Thanks guys but sorry no plans for the holder. I just built it to fit the AXA tool holder, the tool bit slot is cut with a 12 degree forward and 12 degree right angle. The grind on the tool is 30 degrees, in the photo its much steeper than 30 degrees as I was playing around with angles. A 30 degree grind seems to be optimum. Here's a short video showing a cut in 6061 aluminium, its does as great job in 1018 steel as well.

[ame]http://www.youtube.com/watch?v=563MByTYAfY&feature=share&list=UUj2oz2mbTQ_G4h_uC8KPmkQ[/ame]
 
Can this tool be set-up in a QCTP with the shank perpendicular to the lathe axis yet present the cutting tool so it can both turn and face without a change in position? I have an original but it requires a rotation of the tool post for the separate operations. Am I missing something or would that be possible?
 
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You bet, both turning and facing cuts are possible without changing the angle of the tool.
 
Can this tool be set-up in a QCTP with the shank perpendicular to the lathe axis yet present the cutting tool so it can both turn and face without a change in position? I have an original but it requires a rotation of the tool post for the separate operations. Am I missing something or would that be possible?

with a square tool you would need to be careful with setup but it is possible to do both without moving the tool. the rake is at a compound angle so it works in both directions and tilting the tool at even angles in both directions would give you just enough lead angle and releif in both directions to make it work.
 
With the tool held at an angle the cutting surface is more diamond shaped so there is a good bit of relief angle on both surfaces. The trick is the angle of the tool shank. My older commercially made tool doesn't have that angle correct so I have to rotate it a few degrees to change from turning to facing. Sounds like Shawn got that angle right.
 
The only issue I have with this tool holder is the long thin chip it creates, if you let it pile up too deep it can be hazardous to your health when it gets caught up in the chuck. I was running the lathe one handed so the feeds are a bit awkward to watch.

[ame="http://youtu.be/NIRSmK4Ethw"]http://youtu.be/NIRSmK4Ethw[/ame]

Shawn
 
That's a down-side, I have 9 stitches in a finger caused by removing a long stainless steel serrated razor blade produced by mine. Thought I was clear but the end caught on something. But, that can happen with almost any tool. I suppose It's possible to grind a chip-breaker without too much trouble.
On another note, the new "diamond" tool holders are angled differently now and can be set in a QCTP for both turning & facing without being re-positioned.
 
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