MemberOctober 30, 2018 at 6:32 pm
Getting this issue when cutting into 3mm Alupanel, front face is perfect (the side of the sheet which is face down on the bed), but this side seems to have the ali pulled back, very evenly and uniform, as oppose to cut.
Cutting speeds are all where they should be (20,000 revs, 20 mm/s feed and 10 mm/s plunge), brand new bit, 3mm upward spiral flute, no obvious movement in the material (and even if there was I don’t think it would cause this), sent cutter round both ways and makes no difference.
Been cutting intricate Perspex & Foam shapes out today without issue (with a different tool of course).
Does seem like an issue between the tool and tool path that’s causing the ali to be dragged upwards rather than cut through but not sure why :rollseyes:
mod-edit Please use the file attachment facilities provided.
MemberOctober 30, 2018 at 7:15 pm
Have you tried slowing the travel speed?
Are you cutting through in one pass?
Have you tried a two pass with the first pass just through the metal layer?
Have you tried a down cutting spiral?
Just few things I’d be thinking off.
MemberOctober 30, 2018 at 8:40 pm
I get something similar when my router bit is getting worn, but as you are running with a new bit then I would suggest you try reducing the revs to 8,000 as 20,000 seems a bit high to me? Maybe also reduce the travel speed as well?
MemberOctober 31, 2018 at 1:58 pm
Reducing travel speed doesn’t have any effect, reducing the revs does but still a poor cut (poor in there is a still a lip, smaller and more jagged), cut in both one pass and two, cutting down in a spiral as in on a ramp? Don’t think this would solve it as the problem is all the way around, rather than just where the bit initially enters the material.
It does seem entirely like a tool issue to me too, but as I say tool bit is brand new and suited for composite. It’s as if the ali is being pulled up and away from the sheet before it can be cut rather than cut cleanly as the tool passes.
Keep fiddling I guess and we’ll crack it
MemberOctober 31, 2018 at 2:27 pm
The cut looks very rough to me as if the cutter is blunt. Is it a tungsten carbide cutter mill?
If the example in the photo was cut in a clockwise direction, it looks as if the cutter may not be clearing the swarf quickly enough and is pushing swarf in front of the cutter which, when being expelled upward is lifting the the metal lamination before the cutter can complete the 180 deg rotation. A bit like a pressure wave.
What like is the cut on the other piece (the waste part)?
MemberOctober 31, 2018 at 3:20 pm
What type/brand of composite are you using, not hoarding board is it?
MemberNovember 1, 2018 at 5:57 am
I’m with Rob ^^^^ – have you tried different composites?
MemberNovember 1, 2018 at 10:26 am
The tool is a carbide bit yeh, coated too, 1001 Series from ITC and the composite is 0.3mm skin branded Alupanel
Neil, the waste part is always equally as bad, rather than worse or better and sent round both ways.
The cut seems to be much better the faster the feed rate, it’s almost perfect on the back side now, but it’s now caused the front (the underside of the sheet) to fray
MemberNovember 1, 2018 at 10:38 am
It’s difficult to see in the photo but it looks like the core isn’t cut very clean either. It looks a little lumpy? Perhaps the wrong type of cutter, intended for drilling, so only the bottom edges will be sharpened to cut? If it *IS* the proper cutter for the job perhaps it’s a duff cutter. I’ve never had one but I suppose it’s not impossible. I’d phone ITC and ask to chat to somebody technical about it.
I’d think even if it was cheap material, if cutting in two passes with the first cut just through the metal layer, it would still cut a lot better than the example in the photo.
MemberNovember 1, 2018 at 11:07 am
Seems to all be resolved now, joys of now tooling :yawn:
Took what you said Neil about it potentially not clearing the swarf quick enough, so ramped up the revs, along with fixing screws around edge of material to remove any possible movement and it’s cut brilliantly.
Between that first photo I showed you guys though and now, after all the adjusting of various settings the only thing changed by the end compared with original set up was upped the revs by 5000 rpm and screwed material down (it was already previously clamped).
Cheers chaps, can get all these jobs cut now :claps:
MemberNovember 1, 2018 at 8:46 pm
Good stuff Michael.
Log in to reply.