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Vaughan Raymond
10-27-2008, 1:07 AM
I don't post too often but I thought I'd share my interesting day with the laser. We had a job today that involved cutting several hundred letters from 1/8" black acrylic. I had convinced the customer that this was better than doing it with the CNC router in Alu Panel as there would be no handwork. The acrylic material we got had plastic film on both sides. We did some initial letters but the plastic film was time consuming to get off and sometimes left a bit of a mark on the letters. My wife got the bright idea to remove the masking first and then cover the acrylic with wet newspaper. Well, this worked great except that the purge gas coming out of the gas jet nozzle kept blowing an air "bubble" under the newspaper and rendering the protection ineffective. I got the next bright idea of making a shorter gas jet nozzle so the air wasn't directed right under the newspaper. Fire up the lathe and shortly after, it worked great. The end of the nozzle, being further away from the paper, didn't create the bubble. Of course the individual letters would fall into the grid under the sheet and so I was attempting to remove them as they were cut so as not to have them re-lasered and marked up. Now, normally the gas jet nozzle is so close to the surface that you can't accidentally get any body parts stuck in there. Hmmm.... With the shorter nozzle, it's easier......

I often wondered what a 55 watt laser would do to a finger. It didn't go quite through but nearly! Ouch!

Just thought I'd share my stupidity.

The wet newspaper idea was however, a good one.

Chip Peterson
10-27-2008, 8:55 AM
You mean there are no safety lockouts on your laser, or did you bypass them?

Either way, bet you won't do that again!

David Fairfield
10-27-2008, 9:03 AM
You operated that bad boy with the lid open and your hands in there? I like to break rules but that's one I haven't had the courage to try.

If parts blowing around is a problem its possible to elevate the material on even sized blocks, a little less thick than the material you're cutting. So the cut pieces drop a little onto the vector grid, they're out of the way of the air stream and still surrounded by the material, so they don't move around. In theory anyway~!

Dave

Phil Salvati
10-27-2008, 9:43 AM
Glad to hear I'm not the only one with a similar day....

I had to bypass the door switches to do a leather job....two or three times I leaned in to check progression, Each time I thought I was getting shocked...getting madder each time thinking about the down time investigating and fixing the short. Lasering leather smells like skin burning so the smell wasn't a tell-tale!

Upon final progress check I noticed blank spots in the design....after a little investigation and the welts on my knuckles the problem was easily solved!

Mike Null
10-27-2008, 12:25 PM
I am resisting the temptation to remove this thread in the hope that nobody will have such bad judgment to emulate these examples.

While it may sometimes necessary to bypass the interlocks it is never necessary to put body parts in the path of the laser. There are a number of words I could use to describe this but I will refrain lest I lose this high-paying moderator's job.

Kim Vellore
10-27-2008, 12:36 PM
A few burns will heal no problem there but if it hit the eyes due to some stray reflection it is permanent damage, hope you had your safety glasses on.

Kim

Ray Uebner
10-28-2008, 12:55 PM
If it don't fit in the laser with everything in place don't do it. NEVER NEVER put any part of YOUR body into a running laser. What were you thinking of. There is only one you and no job is worth damaging yourself. Just my two cents worth. Boy you were lucky this time.