Cut Through amount

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Kerry Fullington
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Cut Through amount

Post by Kerry Fullington »

We are continuously having to increase the Control Nesting cut Through setting to keep from leaving a skin.

What are some of the reasons that this might happen, compression of the table board over time, or what else? We are at .006 right now. (this setting barely scores the waste board) About 6 months ago we were getting clean cuts at .002

What should I look for?
Josh Rayburn
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Re: Cut Through amount

Post by Josh Rayburn »

Kerry, is the cut through amount being added to your code?
How often are you cutting the wasteboard and spoilboard?
What type of flycutter or tool are you using to cut the wasteboard, and is it being measured properly? Dull inserts can cause the tool to cut improperly and result in a bad wasteboard thickness even after it's cut. Has the humidity changed drastically?
.....lots of variables.....
jnr
Josh Rayburn
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Kerry Fullington
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Re: Cut Through amount

Post by Kerry Fullington »

Josh,

I haven't checked the code but I will do that as a starting point.

We rotated the fly cutter inserts about two weeks ago and of course re-measured the tool. I have also re-measured all the other tools.

Humidity could be a big factor. We are at about 16% now. Summers we can be at 80% here in Dalhart (from all the irrigation) but Amarillo where the machine is would not be quite that high.

I re-measured the outline tool Sunday when I noticed this and there was .005 difference in the daylight value but I still had to use the .006 cut through and still had some fuzz on the bottom veneer.
Josh Rayburn
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Re: Cut Through amount

Post by Josh Rayburn »

Kerry,
I would be sure to cut the wasteboards every week at least. You don't need to take a lot off them if they look clean, but as long as they're what the machine thinks they are then you should be good. If they seem clean then cut them at the same thickness they already are and see if it takes anything off or even hits the wasteboard at all.
The spoilboard should be cut (from my experience, I don't know what TWD recommends) every six months, timed appropriately with seasonal changes to be sure that factor is no longer a variable.
You already checked the inserts but it's imperative that they don't get too dull before rotating or replacing since they could be measured improperly when dull.
The cut through amount has been broken in the past and I don't know what version of CN you're using but the code will tell you if that's broken or not.
The tooling measurements should be done with the vacuum on so specks of dust don't sit on the measuring plate. I also like to blow it off real good before measuring anyway.
These are all things you probably thought of already - but maybe it will help get rid of variables and you can see if you still have a problem after these are out of the equation.
Are your fits good on the parts that are coming off the machine or have you noticed it getting tighter or looser?
jnr
Josh Rayburn
Hall's Edge, Inc.
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Rob Davis
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Re: Cut Through amount

Post by Rob Davis »

Kerry, my two cents..... When we flycut, we have to fake the machine into thinking the board is 0.002 lower than what we actually cut it to be. I think this is because when we have the waste board on the machine with nothing else, it doesn't compress fully because there isn't enough vacuum to pull it hard enough. (too much surface area exposed) If we cut 3/4 melamine right behind surfacing, we get a really good pull and this is how we discovered the difference as either the weight or the suction or combination of both caused the melamine to pull the waste board down tighter to the spoil board. So when we are done cutting the waste board, when we go into M999 in Tool Measure to set our switchspoil, we actually tell it the board is 0.002 lower than it theoretically should be. And we cut through by .002.
Another anecdotal observation is that the thinner our waste board gets, the more fuzz we get. Can't explain it, just what we notice. Maybe just random. It seems that when we have a fresh waste board we don't need to fake this measurement but as we get thinner and start leaving fuzz, we change it.
Ray Jorgensen
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Re: Cut Through amount

Post by Ray Jorgensen »

Kerri,

I know that humidity changes will effect the thickness. Right now I'm having quite a time. We'v'e been having periods of ) degrees (where the furnaqce runs lots) to periods of 50 degress and humid. If I fly cut after a couple of the warm humid days and then we get a few cold days, I'll have to play with the wasteboard thickness to get rid of skin. Normally this only causes a problem in spring and fall, not this winter!!!
Steve Detina
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Re: Cut Through amount

Post by Steve Detina »

Morning Kerry,

We have the same issues from time to time as well. We are able to dial in the cut through by doing the following.

Machine our waste board on both sides.
Remeasure our tools each morning (we actually loosen the nut, blow out the tool, and then re-tighten the nut again)
After we surface, in the control I do a ghost run (manual panel input) and this will determine the actual cut through.
If the cut through is to deep we reduce the value, if it is not enough then we increase. This takes all of 15 minutes and
ensures that you get proper cut through for the rest of the day.

Hope this helps

Steve
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