Acrylic parts with close spacing Welded after a Cut

[Tim Mellor]

General question and I know the answer is easy just space out your parts more. I was cutting a Router Template today for a Drill base I am making and to save material I set the sacrificial plate inside the Template I was cutting.

As you can see from the Drawing the line spacing is under 2mm and then the software would have allowed another 0.18mm for the Kerf so just under 1.5mm between the cuts. The strip post cutting came out at just over 1.4mm on average. 3/16"- 4.5mm thick acrylic btw.

BUT along reasonable portions of the strip it had I assume rewelded to the inner panel which my software cut first. It wasn't an issue for me as it didn't take much to split it with a knife post cutting but cosmetically on a finished showing edge it would look a bit messy. The inner square with strip came away clean from the outer section.

So how close do you or have you run your parts in Acrylic and have you had similar issues with close separations?

[Gene Uselman]

My normal spacing if I use RDw to layout copies is .050- so about 1.5mm- no issues. I would look at your air assist pressure first- I like pretty hi press to blow the debris out the bottom [cutting on blade bed].

I use the shop air supply with a press regulator BTW

[Doug Fisher]

At least two mm, often 3 mm. I have been "burned" when using less in the past so I just use these out of habit versus any scientific research!

[Dan Torrey]

Tim, on a side note, you have stated the kerf that is allowed by the software is .18mm. What lens do you use to attain that slight of a kerf. My understanding is the kerf is the diameter of the hole made by the laser. Using a 2" fl meniscus lens the diameter/kerf I have is .5mm. I am new to this so I may not be fully understanding the terminology.