Author Topic: Selective cutting  (Read 485 times)

pedwards2932

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Selective cutting
« on: June 09, 2020, 12:54:27 PM »
When I am cutting balsa I try to cut as fast as I can to minimize charring.  Because of this sometimes it doesn't cut all the way thru on some pieces because of different density.  Is there anyway in T2 to selectively pick which part you want to make a second pass?  I have my burn board set up so I can look at the balsa to see if it cut thru and put it back in exactly the same spot.  I guess I could run another dxf file but that would be a pain.

Zax

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Re: Selective cutting
« Reply #1 on: June 09, 2020, 03:24:14 PM »
No, but if it's due to grain you can automatically compensate for that and cut with more power (actually a slower speed) using the vector adjustment feature.

To minimize charring increase the feed rate and run an additional pass or two, alternatively turn up your air assist and drop the feed rate so it cuts all the way through.

pedwards2932

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Re: Selective cutting
« Reply #2 on: June 09, 2020, 03:39:02 PM »
I am still working with the air assist but I am using a airbrush compressor so I am getting a fair amount of air.  If I cut at 800 mm/min there is almost no charring and it goes thru in a lot of places.  I had to turn down to 575 mm/min and it cut thru almost all but there was a small amount of charring. I still had to take out an exacto and cut thru a couple of places.  I think the density in balsa is not consistent and cross grain can be an issue.  I didn't notice it except in the harder sections of the wood.  Next time I will try 800 and push out the pieces that are free so they don't get the second pass. Since it doesn't just happen on cross grain but in different sections of the wood I don't think vector adjustment would help.

Zax

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Re: Selective cutting
« Reply #3 on: June 09, 2020, 03:56:00 PM »
I often run an extra pass just to cut the fibers that remain, that way the pieces drop out.

Do you have a raised table like a honeycomb or grid material, if not that helps as the char can be pushed out the bottom as the laser cuts.

pedwards2932

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Re: Selective cutting
« Reply #4 on: June 09, 2020, 04:29:41 PM »
I made a burn board that has a .020 metal glued to a mdf board.  I printed up some holding devices that uses magnets and the balsa has about 5mm of air between it and the metal

Zax

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Re: Selective cutting
« Reply #5 on: June 09, 2020, 04:33:24 PM »
Nice, that looks like it would work well.