Chatter marks in cherry

1

Making round catch-all trays in cherry. Experiencing chatter marks in the profile cutout. Never seen these before. The wall thickness is 0.4 in.The bit is new and the feeds and speeds are: 90ipm, 40 plunge, and 0.15 doc with a .1/4 inch downtown Jenny. Bit is well up into the collet so there’s no noticable deflection or shaft runout. Interior pockets look just fine, it’s just the profile cutout that looks bad.

Any ideas?

Tom

1 Like
2

Is the part moving on the last few passes on the outside contour? Might not be typical chatter and could be a work holding issue.

1 Like
3

No movement that I can see. Material is secure to wasteboard via blue tape and CA glue plus T-bolt clamps on 4 corners (making the trays 4-up).

Tom

1 Like
4

Just in case, I’m going to rerun the job and use tabs .

Thanks for your suggestion.

Tom

2 Likes
5

Normally cherry cuts very well. Try reversing the direction of the cut, or the bit cut from conventional to climb or vice versa. Or try slowing the speed down to 60ipm.
Pony

1 Like
6

Thanks. I plan to rerun it tomorrow. I’ll report back with results. Thanks,

Tom

7

Tom,
I received some chatter yesterday using a Makita router. I discovered I was running the router too slow. I increased the speed and it cut great. If you are using a spindle you should be running at a regular speed since the bit changes speed based on tool database speed setting.

Dave

1 Like
8

Dave

I am running a Makita router. What speed setting do you suggest?

Tom

1 Like
9

If you have your tool database set up with a speed value and the chip load calculates right use that. I don’t have the number to speed chart here but I would run close to 3 and see how that sounds.

10

I don’t have a database for Onefinity. I did just run the job again and it looks better. I ran it at 3. I’ve reached out for to Cody at Cadence to get the numbers for his bits for the Onefinity…

Tom

1 Like