Re: Knocking sound when plunging
Originally Posted by
Jonnygexter
I tried reducing the plunge rate to 30mm/min and the depth per pass to 0.2mm, but no change.
30mm/min is way slow for polycarbonate, you want to be making chips not heat. If the tool path suits ramping do that instead of plunging. Ramping can be helical or sloping deeper as the tool follows a contour or slot.
I fear this knocking sound is bad for the machine and could break the bit... so I don't know what to do. Any advice? Thanks.
I don't know the source of the noise but if a tool is punching through instead of cutting the sound isn't pleasant.
... but re-reading the description I see now that the single edged bits are steel. Could the weaker steel have anything to do with it?
I've read HSS works well in plastics, something to do with sharper cutting edges compared to carbides. It's not a theory I've tested, carbides work fine for me.
Anyone who says "It only goes together one way" has no imagination.