Boring bar holder ineffective

[mksj]

If the split ring does not clamp fully then probably wrong size boring bar and/or spot ring does not have a wide enough split. I did add two screws to the top of my boring bar holder that go through the split ring and push directly on the boring bar flat. This was so it always maintains the same rotational position when moving it in/out. On smaller boring bars I use #2 tool post holders that have a groove on the bottom for boring bars.

 

[OTmachine]

If the split ring does not clamp fully then probably wrong size boring bar and/or spot ring does not have a wide enough split. I did add two screws to the top of my boring bar holder that go through the split ring and push directly on the boring bar flat. This was so it always maintains the same rotational position when moving it in/out. On smaller boring bars I use #2 tool post holders that have a groove on the bottom for boring bars.
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Good idea! Most all of our W&S turret and bar machines had holes in the bushings to facilitate set screws locating on the machined top flat of boring bars. Guarantees proper orientation of boring bar. Probably not a bad idea to do away with the clamp type bushing and make new sleeves for the holders with the added holes to use added top set screws as you have done.

 

[Danzo187]

I have an AXA boring bar holder that uses two bushings to hold a 1/2" boring bar. But the bar almost spins like a top... the grip is not strong at all. I have disassembled to check for defects or issues. Perhaps the issue is the user. Any suggestions?
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DanK

if the split on bushing is not straight up or down (vertical) the screws will put the force on the slot therefore not enough force to close bushing.
but looking at you're bushing it should tighten in any position, just run a slitting saw through it, even a small end mill or a hacksaw, a grinder, whatever you have

 

[Batmanacw]

My efforts from today. Don't mind the drag marks on the 1/2" bushing...lol. Brain fart.


3/8"




1/2"

 

[David2011]

Batman, those look really solid. Good job.

 

[verbotenwhisky]

My efforts from today. Don't mind the drag marks on the 1/2" bushing...lol. Brain fart.


3/8"
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1/2"

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I have my small bar like that is a standard tool holder that has a v cut in the bottom of it.

 

[Batmanacw]

I have my small bar like that is a standard tool holder that has a v cut in the bottom of it.

I like the support in the round holder better.

 

[pontiac428]

You could make a _XA tool holder out of recycled pallet slat lumber held with deck screws and it would still be more rigid than a 1/2” boring bar with 3" of stickout, so there is a low ceiling when it comes to holding the tool solidly. Of course we aim for ideal, but a noodle is a noodle.

Good work though, looks solid.

 

[Batmanacw]

You could make a _XA tool holder out of recycled pallet slat lumber held with deck screws and it would still be more rigid than a 1/2” boring bar with 3" of stickout, so there is a low ceiling when it comes to holding the tool solidly. Of course we aim for ideal, but a noodle is a noodle.

Good work though, looks solid.

Who are you referring to?

My little 1/2" boring bar is a solid carbide noodle. Should be good for noodling out to around 4" max at 8 times diameter. More of I'm noodling super careful.

 

[pontiac428]

That is a very nice noodle, then! I guess what I mean is that the double all-beef patty tool holder is a lot of extra beef over a plain tool holder when holding a tool that sees plenty of deep bore deflection and head twist oscillation at rather low cutting forces compared to a 1/2" square profiling tool, so the beef is superfluous at a certain point. But everyone loves a well-supported tool.