CNC cutting off path (PRO Series)

Original/PRO Series (Buildbotics) (Gen 1)
1

Hello,

I am new to CNCing and got a used onefinity Pro Journeyman from someone. I am running some cuts and the CNC seems to drift off the path randomly. I adjust the stepover, RPMs, feed rate and even changed the bit and its still doing it.

It seems to be having a hard time with corners too.

Photos

Machine: Onefinity PRO Journeyman
Bit: 1/4” downcut end mill
Program: VCarve Pro
RPM: 16000
Feed Rate: 60
Plunge: 20
Stepover: 40%, tried again at 20% and again at 10%. Had similar issue each time, just in a different location
Passes: 8
Wood: Cherry
Held down with 4 brad nails in the corners

I checked the screws on the machine and everything seems tight. I even changed the bit to an 1/8” downcut and the issue seemed to get worse.

2

What is your depth of cut per pass?
If it’s 1” thick that’s 1/8 “ per pass. If so try and reduce say 1/16” see if there’s a difference
Are you using any dust collection?
Have you gone through the maintenance video? It could be dirt in the ball screw

3

I was doing just under 1/8” per pass. I am using dust collection, what’s the ball screw? Do you have any maintenance videos you’d recommend?

4

Check this out

5

Thank you, I’ll clean the machine and see if the problem persists. Appreciate the help!

6

I would also doubt check your hold downs. With your piece nailed down, can you move you part at all?

7

Since you bought it used, is it possible that the “red motor couplings” were somehow left out?

If you don’t know, search this forum for “Red motor coupling, Don’t throw away”.

8

Were you using any tabs to hold the piece in place while cutting?
If the Brad nails were in the corners the piece may not be secure causing the shift in the outside profile
If you dont want to use tabs then leave .005 thickness on the piece remaining .It solves two issue 1 it holds the piece secure and 2 it prevents cutting into the spoilboard.
Just use a utility knife to cut the “ onion skin” remaining free.

IMG_0540
IMG_05401920×2560 815 KB

9

It’s held down solid with the brads, there is no shake to it at all and getting the piece off the bed is a challenge haha It will mess up the very first pass so I know it’s not he material moving

10

Yes, two tabs and the brads are holding it firmly. It will mess up and cut off the path on the very first pass sometimes. I haven’t had a chance to do maintenance on the machine, but just ordered the oil so will do that on Monday :slight_smile:

11

Thankfully those are there and he didn’t throw them away. That was my concern though - that maybe the machine wasn’t built correctly. I debated taking it apart and rebuilding it, but I don’t even know where to start

12

Is this a file you created or one that was downloaded?
Sometimes download files have many node points or layered vectors which can throw off a cut

13

Have you tried it without your dust collector on? Might could be static