VEX allows “Any non-shattering plastic on the robot was cut from a single sheet of 0.070” material not larger than 12"x24".
Where do you buy your plastic, and how do you cut it?
Do you know of any type of non-shattering plastic legal for VEX that can be laser cut?
Thanks,
Mr. Trimble | Engineering/Robotics Teacher | http://hrvrobotics.org
My team got this plastic, and uses a dremel to cut it, sanding and filing the cut edge afterwards.
We get our plastic from robosource.net Price is good, and pre-cut sizes are convenient. They carry both polycarbonate and ABS. Typically, our students just bandsaw or shear to size, and drill holes…no laser cutting.
I have looked into this a bit. The short answer is no. The long answer is its not recommended.
It is common to use polycarbonate or ABS both which don’t do well in laser cutters. When laser cut both can release toxic gases and if you ignore the toxic gases it just doesn’t cut well. Dangers of the material catching fire as well. Now with the correct precautions you can trryyyy but its very much not recommended.
I have used a handsaw, bandsaw, scroll saw, Dremel, shears, and CNC to cut polycarbonate. Using a handsaw or shears for more rough applications, like cutting a square or rectangle, and more precise tools to get more complex parts. If you use cad to create complex parts I suggest printing a sheet of paper and tracing where you want to cut with the paper.
PETG seems like the best bet in terms of being both laser-safe and VRC-legal, see this post:
If you don’t care about laser cutting, polycarbonate and ABS are the most popular plastics by far.
Sound cutting and bolting advice here: How to cut and screw polycarbonate sheets? - #9 by Unionjackjz
Looking at @u89djt’s link, I would also recommend buying aviation snips or compound action snips. These snips cut much smoother than just normal tin snips. They can also be used for metal. From experience, you can cut a piece of 1 by 2 with just one hand on the snip and the other holding the metal.
I bought the exact product @Unionjackjz linked to, and they are in fact especially good at creating clean unwarped cuts in polycarbonate sheet.
ABS releases really toxic gas. Do not laser cut. Nor should you laser cut PVC. Both give off gases you don’t want.
However, polycarb above about 1/16 does not laser well, that is true. It makes a mess, smells horrible, and can damage your laser optics from soot if you don’t have good exhaust… But it does not produce toxic gas. That’s a bit of misinformation. Most places that say they won’t cut polycarbonate is mostly because of the mess and poor surface finish.
In my experience the gas is flammable, though I don’t have any science to back that up. Just that I have caught my 40W laser cutter on fire and I think it was the gases fault.
To be clear, I am not advocating or recommending laser cutting polycarbonate. Just trying to squash some myths about toxic gas and PC.
All that being said, onto the real reason I am replying to this thread.
If you happen to have some old VRC or VIQC fields laying around, there is some useful plastic that can be scavenged!
I know there are more, but the few that come to mind are the Flags from Turning Point, the goal from Bankshot, the Platform tops from Tipping Point, the plastic sheets from Pitching In, and the backboards from Change Up.
While these platforms are a good source of plastic for other uses, as clarified in Q&A 975 they are not legal for VRC, so don’t try to bring it to a competition.
https://www.robotevents.com/VRC/2021-2022/QA/975
The platform tops from Turning Point (the 2018-19 VRC game) are too think to use as legal plastics on a VRC robot.
The platform tops from Tipping Point (the 2021-22 VRC game) are under the maximum thickness.
Ugh…
While you are right in that’s what the Q&A answer says… @holbrook is technically right.
Let me talk to some people…
I did run a laser cutter on polycarb a few years back to help VEX team 69 I was mentoring. (First time using laser cutter, manufacturing isn’t really my area)
Really do no recommend.
Ah my bad. Sorry about that.
I would say that a CNC router is far superior when it comes to cutting lexan. And if someone is shy about cutting with a router, you can always put a sharpee on it instead, using the CNC to mark a stencil to cut out yourself using a band saw. Nowadays routers can be bought for a reasonable price, and with community involvement and support you can make the CNC more accurate and precise over a period of time.
Of course, you wouldn’t move the laser cutter around by hand 
.
Taran is referring to the fact in the vex discord I posted about how Connor was not using precise language. A laser cutter is a CNC. A CNC just means machine is computer controlled, as opposed to controlling it by hand or moving the tool by hand. CNC has nothing to do with what type of machine is being controlled. CNC lathe, CNC mill, CNC laser cutter, CNC router.
In this case presumably @Connor meant a CNC router. (this has been a pretty common colloquialism in the vex community the last few years that I don’t particularly like)
I did use a CO2 Epilog Laser Cutter to cut my polycarbonate. The cuts were clean and came out perfectly. I used the large sheet of polycarbonate sold on VEX and West Coast Products and kept the plastic covering on when I cut it to avoid any burn marks on the polycarbonate. This is by far the best way to cut polycarbonate in my opinion.
My apologies. You are correct, I was meaning a CNC router.
CNC mills? Aren’t they expensive?
I just use tin snips and sheer force (not that I have much of that)