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Partical board problem9/21
Hi all hope your doing great
I am facing a big problem when nesting double faced melamine partical board,
Hope u can help me with that thank u all
I would check your feed speed and RPM.
You are likely going to fast or too slow. I do not work with PB, but that is my best advise. Doing what I suggested should also get you the proper feed speed that makes the bit last the longest.
Did you start using a new brand of board? I can see a significant difference from one brand/grade to another.
Its a doing this for all kind of chipboard ... This picture show my problem
How many passes are you doing? Sometimes a 2nd pass will clean up this type of fuzz.
Are you climb or conventional cutting? Conventional cutting will typically leave a cleaner edge.
Feed rate and rpm? Too fast a feed rate combined with too low an rpm can cause this type of problem.
Thank you for your responses
Too fast for a 2 flute tool.
My edges start to go away above 850 IPM
Was it always like this or was it good and then go away?
I suspect you're still running too fast. I'd drop to 960 IPM and see what happens.
I find coated bits work better longer.
No PCD. The melamine paper puts grooves in the bits. Also a lot slower cut speed.
I tried 3 flutes for a bit but ended up breaking them. Back to 2 flutes at 850 IPM for me.
thank you for your help
so by your experience i understand that it is possible to get a clean edge with a cnc router
Absolutely should be no problem getting a clean edge. One more thought.....a dull bit would cause that sort of fuzzing also.
should i do 2 passes for an 18 mm sheet of double faced melamine chipboard
first pass climb cut
That's what I do.
What diameter bit are you using? The chip load for particle board using a 3/8 bit is .02 to .023 per flute. The chip load for a 1/2 bit is .025 to .027 per flute. This is a great starting point that you can adjust based upon the quality you see. I referenced a link to Vortex's chip load chart for you.
If you are using a 3 flute 3/8 bit at the high end of .023 per flute you would use the following formula- 3(number of flutes) x .023 = .069 x 16000 (rpm) = 1104 ipm. This is a starting point.
Here's the problem with either of these scenarios. You're CNC may be capable of cutting at those speeds in a straight line but what happens when you go around corners and arches? The machine is going to slow down while your spindle cuts at the same RPM. This is going to quickly dull your bit and before you know it you'll have bad edges.
I recently did a time study for a customer that was cutting out 5 x 7 inch pieces at a programmed rate of 800 ipm. It took 26 minutes to run the program on his machine (Busellato) I ran the same program at the same programmed feed rate of 800 ipm on the machine that I sell and it took 11:34 to run on the rack and pinion machine and 9:42 on the linear machine. The first point to note is none of the machines reached or maintained the programmed speed of 800 ipm not even the linear machine. The second point to note is that the acceleration and deceleration varies greatly from one machine to another. Depending on your machine you may do better with a 2 flute bit that allows for slower linear speeds that will be more inline with the speed your machine will run in corners. You may be dulling your bit rather quickly due to the acceleration/deceleration of your machine in the corners and arcs.