I recently discovered our school’s Laser Cutter and was wondering how it worked on Lexan. I know a few teams have mentioned it in the past, but I didn’t know much about it and wanted to research it first. I Googled it and found a few forums discussing the topic. About half of the people answered that it worked fine, so on, blah blah blah, but a noticeable amount of the forum users talked about discoloration problems and even some form of Chlorine Gas release (Highly Toxic).
I imagine they were using different thickness/brand/whatever, but I just wanted to check to see if it was safe with the Vex community who has experience with this sort of matter.
In addition, are there any tips for someone inexperienced with the process? What is the optimum Thickness of Lexan, Power, etc.?
I would talk to Zak (2880A). He was talking to me the other day about how he was laser-cutting his lexan. PM him and I’m sure he can give you good information
Optimum thickness depends on the laser wattage and what collimating lens you use. Generally you can cut up to 1/4" or so before you start to notice angled cuts and long cut times.
To see if stuff contains chlorine, look up its Material safety data sheet or burn a small chunk of it. If the flame is green, it’s probably PVC and should not be cut.
Lexan/acrylic/polycarb should be okay, it just smells nasty.
Source: I laser cut and waterjet stuff everyday for my research work.
A fume hood never hurt anybody… or just keep your work area well ventilated. I took the liberty to look up Lexan and it doesn’t have any Chlorine. So unless you’re not using lexan, should be good (in which case you’d have to look it up).
What are you doing at MIT that you’re laser cutting as an EECS?
Jesse:
Zak is actually one of my best friends, we’re from the same town, same school and he often comes over to use our field and scrimmage, so I know him quite well.
I was almost 2880X but ended up getting my own number.
He told me about it today and I wanted to get some more info on it because I want to implement it on our robot next year. When I saw that there might be some danger I wanted to check with teams with more experience to make sure we didn’t poison ourselves.
MediumDave:
Thanks! Zak (2880A and good friend if you read above) is cutting some things tomorrow, so I suppose I’ll just go and test some sheets out for myself.
haha yeah I figured you guys where I’m pretty sure we were allianced at US Nationals during the Gateway Season (I was 323B). You guys were fun to work with, and I hope to talk at Worlds (and Open).
If I can find someone to do laser cutting, I want to do that. It’s so much cleaner than a hacksaw Water-jets work on lexan correct? We have a sponsor that could water-jet cut and I think we might do that if it will work.
Does anyone know how well cutting with a hand held jigsaw works? I’ll be trying it anyways tomorrow, but was wondering if anyone know or had some tips.
As for the toxic fumes, take a look at the MSDS for the product you are using. A quick search got this for lexan and this for makrolon. You should probably verify though that they are the correct and up to date versions.
So yes, it is true i have access to the worlds fastest Laser Cutter (MIT, Rice, and Stanford have one too :)) And yet my school can’t afford to send a couple of children to the World Championship.
But i do believe that my lexan does not contain Chlorine, I will test cut some things tomorrow, and show them off in our Teaser Thread.
BTW, if you guys PM me i might be able to cut some stuff for Ya! (only 1 item per team, if that)
That was us, It was amazing to get anywhere in our first year.
We’ve changed numbers multiple times since then… I’m kind of surprised you remembered!
While 323Z was off becoming a legend last season (Sack Attack), we fell into some dark times with a lot more to learn before we moved on past rookieness, but we have seem to come back from that.
Although I was a bit sad when I saw 323Z wasn’t signed up, the Team List for the Open is looking very tough and I’m sure it will very intense.
After further review of Laser cutting, and Polycarb… I have decided that it is a “high risk” since the Laser is inside of a classroom, and not a lab. So disregard the offer on Laser Cutting… Sorry folks
I’m a mechanical engineer with robotics now…should change my signature.
Is this a freestanding laser cutter? The ones I’ve seen normally have a big ol’ exhaust tube to the roof or a filter system. Could you use the laser cutter outside?
Barring that, you can get it made pretty cheaply from ponoko or big blue saw.
We’re not supposed to laser cut polycarbonate/lexan on ours at UBC, but it’s enclosed with a vent, so I think it’s more an awful smell than extremely dangerous. Still, I wouldn’t really chance it.
Water jets work on EVERYTHING, so go nuts. The only disadvantage is the price goes from the cost of energy to the cost of sand (non-zero).
Tin snips work in my experience, but it’s not CAM precision.
I thought I was the same year as you: 2nd year (Engineering Physics, Mechatronics).
For anyone who may care, I tried cutting with a handheld jigsaw, and it actually worked even better than expected, even though I only had a wood bit available. The cuts are straight and neat, and is way faster than doing it by hand. If you want to avoid your hand vibrating loose when holding the piece that will fall off at the end, clamp the sheet between two tables. Also, it is easier to get the start right on the line if you do the first inch or so with a handsaw.
And yes, it specifies that polycarbonate CAN be laser cut. Laser manufacturers also say that polycarb can be cut on their lasers.
But when I look at service provider’s sites, many of them refuse to cut polycarbonate due to the fumes. As I understand it, it isn’t so much that the fumes are particularly hazardous to humans (laser cutters should be well ventilated anyway), as it is that they tend to dirty the mirrors and gum up the mechanics of the laser cutter itself. There comes a point where the labour in cleaning the machine exceeds the labour involved in using a different material or different machining process.
We’ve been using our engraver to cut polycarbonate for a year. So far we haven’t had any trouble and since the lazer is programmable, the parts are precise. But always be careful. That is always the principle.
Our laser engraver does the same thing. The lexan we buy comes with plastic on both sides so we leave it on while cutting then take the plastic sheets off and the lexan is spotless. Also, you might be able to adjust your engraver settings to cut at a faster speed so in order to prevent the extreme burning of the edges. (If you do it faster, you might also have to cut it a few times before it goes through)
I’m pretty sure we were allianced at US Nationals during the Gateway Season (I was 323B). You guys were fun to work with, and I hope to talk at Worlds (and Open).
