harryball
09-14-2006, 05:08 PM
I'm running a new PRTAlpha96. I tuned the Z axis today and got it to .005" square to the table top. I ran these two plaques.
On the left I used a Bosch 1/4" down spiral bit, the edges of the letters and plaque are crisp, but I get tooling marks in the area clear. These are not ridges like a Z out of square... it's odd I can't figure out what's happening. I even put a shop vac on the table to pull the board down and 4 screws on each corner. I can't understand how the bit could plunge up and down... it'd make you suspect something was wrong with the bot...
Now look a the right, the area clear was done with a 1/4" 2 flute straight bit, a cheap-o at that... the area clear is clean but the letters and edges are not clean.
Here's what I know...
My down spiral keeps the edges clean but compacts chips on a profile cut rather than cleaning them out and leaves tooling marks.
My Freud up spiral clears chips well, leaves the edges in tatters.
My el-cheap-o 1/4" straight bit leaves an almost perfect area clear with not so good edges.
What am I battling here? Is this just a factor of the bits? How is that one down spiral bit responsible for such tooling marks?
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On the left I used a Bosch 1/4" down spiral bit, the edges of the letters and plaque are crisp, but I get tooling marks in the area clear. These are not ridges like a Z out of square... it's odd I can't figure out what's happening. I even put a shop vac on the table to pull the board down and 4 screws on each corner. I can't understand how the bit could plunge up and down... it'd make you suspect something was wrong with the bot...
Now look a the right, the area clear was done with a 1/4" 2 flute straight bit, a cheap-o at that... the area clear is clean but the letters and edges are not clean.
Here's what I know...
My down spiral keeps the edges clean but compacts chips on a profile cut rather than cleaning them out and leaves tooling marks.
My Freud up spiral clears chips well, leaves the edges in tatters.
My el-cheap-o 1/4" straight bit leaves an almost perfect area clear with not so good edges.
What am I battling here? Is this just a factor of the bits? How is that one down spiral bit responsible for such tooling marks?
3735
3736
3737