cutting ribbons instead of chips

[jwa1156]

Cutting a 3D plaque on my desk top using Cherry
during the roughing was getting combo of chips and splinters
.
Now on the finishing cut I am getting ribbons instead of chips
the cut is good, not sure which item is wrong


Bit 1/8 BN
RPM 16000
Feed Rate 1.2 ios
Plunge Rate 0.5

Had been breaking bits and loosing steps during cutting,
lowered my Feed Rate upped31882 the RPS and at least I am not break bits and have not lost any steps in the cutting program in a while

See Attached JPG
Thanks

[dmidkiff]

To fix this one without much sanding I would run again. Might even run in opposite direction. For future, keep playing with the feeds and speeds. 16,000 rpm seems too high to me. The type of wood helps some but I have seen this in oak, maple, walnut, and beech. When it was this bad I ran again. ( even if it is a long file because I hate to sand) If you cut against the grain it seems to help.

[scottp55]

Perhaps try 1.5IPS in all 3 axis, as it will only cut as fast as your slowest axis, and your Z is slowing it down.
16K sounds alright if feeds increased.
Most of my stuff is small, but 1.5IPS works good for me on the Desktop on my stuff over 3X5"(but never done a bigger plaque).
I typically cut against the grain.
scott

[jwa1156]

Scott
Thank you will make the adjustments and see what happens

[scottp55]

Jerry,
If straight .125" BallNose and not a Tapered....make sure where you start the cut doesn't have a lot of material left from the roughing cut!
Just don't want you to plow into a lot of material on the first raster and break a bit.
You can cheat the Z on the first couple passes, by Zeroing as normal, then MN(type MN(Move/Nudge) up to a reasonable first pass and run a few lines...and then MN down in increments to original Z. Usually then it will only be cutting the stepover which is usually safe IF the file doesn't jump from place to place.
T(apered)BN's are a lot more forgiving as they're stronger.
scott