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rotorzoomer
Sun 22 August 2010, 05:00
Took the MM beast for a drive today and ran some cuts and noticed that i am experiencing chatter on the cutting of rounded edges on the board.

- I am using a Makita Router
- 6mm 2 Flute Straight Cutter
- 12mm MDF
- 2500mm per minute feed rate
- Using a 4:1 Gear Reduction Setup
- Straight cuts in both X + Y are perfect

Funny thing is that the board i am cutting is four sided and the chatter marks appears on only 3 of the 4 corners.

Is this a router issue or is the feed rate too high?

javeria
Sun 22 August 2010, 06:12
May be - one or more of the V roller on your Z is loose

rotorzoomer
Sun 22 August 2010, 06:34
It's all tight

I am suspecting that after inspecting the 4 corners, all have various levels of chatter from none to worse which leads me to believe my tabs came loose and where not thick enough.

Any are thoughts on the causes i can check?

normand blais
Sun 22 August 2010, 06:51
Hi maybe 3 corners are made of a bunch of small lines and one is an arc.

rotorzoomer
Sun 22 August 2010, 06:55
I checked that also, that was one of the first things i learnt about CAM and vectors and always ensure i convert to ARC or BEZIER.

Kobus_Joubert
Sun 22 August 2010, 09:53
What is you micro stepping setup?
What is your Mach3 speed and acceleration?
What is the length of the cutter?
Did you cut in one pass ?

Gerald D
Sun 22 August 2010, 12:08
Kobus, 3 passes . . . see the marks

Kenrbass
Sun 22 August 2010, 14:05
Try the first two passes in climb mode and the final in conventional and it will help some.

If it is not segments in your design, it has to be a little slop in the machine somewhere.

Kenneth

rotorzoomer
Mon 23 August 2010, 04:44
After making some noise today and adjusting the thickness and quantity of tabs i concluded that the chatter marks are due to the parts vibrating while cutting and nothing attributed to issues of mechanical nature (Thank Goodness!)

I thickened the tabs to 5mm and she cuts like a laser on the corners now.

To paraphrase Gerald...."The MechMate build is a passing phase, you will have a life time of Toolpathes and CAD / CAM to deal with for the rest of your life"

Gerald D
Mon 23 August 2010, 07:07
Anyway, congrats on getting your machine to cut! :)

smreish
Mon 23 August 2010, 18:15
Congratulations. Wow...the machine builds just keep coming. Funny how that happens. :)