Laser Cutter Suggestions

Technical Manufacturing
1

Hello,
Our team was recently looking into getting a small laser cutter after seeing the one sold by buildyourcnc.com. After talking to the engineering teacher at our school, we were happy and surprised to hear that the school had already purchased one of these kits for the engineering classes however, after a emailing the buildyourcnc tech support we found out that the blackTooth’s CO2 laser doesn’t cut metal. While we can still use it on wood and plastic, I wanted to investigate a little further and see if any teams knew of a system of similar size (this one is 20x24 which was nice because we don’t have a large storage space) that was capable of cutting metal. Thanks

-Jesse

2

I think you’ll have a hard time finding a machine at a reasonable price or size to cut metal. Most metal cutting lasers are targeted at industrial workplaces, and are designed to cut full size 4x8 sheets of metal. Not to mention the wattage required will usually be four figures, which requires some pretty hefty industrial power.

This is the smallest metal cutting laser I’ve ever seen: http://www.hurricanelasers.com/betty

There are plenty of uses for a low-power laser system in FRC though. We make plenty of delrin parts and wood/acrylic prototypes with a machine owned by a local college.

3

I kind of figured that going up to the higher class laser would have a corresponding price jump, but just wanted to double check. Targeting industry makes sense too. Thanks for confirming

4

Maybe Adam can weight in but I thought 973 used laser cut (or was that cnc router?) baltic birch. There is a large chunk of the robot that can be made with wood and plastic.

If you want laser cut metal,your best bet would be to find a shop to do it. Our laser cutting sponsors are pretty easy going because we knock out all our parts in one go.

5

Routered for sure, those guys router like monsters!

-RC

6

For sure. They router a ton of wood and metal. They even router their hole pattern so they don’t have to do it manually.

7

We just got training on the school’s new Universal Laser VLS3.50. The training rep said the rule of thumb is about 10W/0.1" of material thickness for acrylic and light woods.

8

There’s a lasercutter in the lab I work in which 4464 is making good use of. No, it can’t cut metal, but honestly if you’re creative and you know the properties of your materials, it’s surprising the number of things you can do without metal. We mainly use it for delrin, and it’s incredibly useful. Sure, it’d be nicer if we could CNC metal parts, but we’re doing some pretty cool stuff with delrin.

9

This makes me think that even though our team is gifted so many neat tools, like three 3D printers, Laser-cutting machine, 6-axis CNC (upon request), CNC router, all these amazing tools. We have used the 3D printer a couple of times, but nothing much, otherwise.

10

You could use Cermark, mark where you want to cut with it (engraves without destroying laser, comes out black) and then cut the lines with a band saw or something else.

11

That is a really interesting idea that I hadn’t considered before. Thanks!

12

Delrin always melted well before it even cut through the last time I tried laser cutting it. ABS worked really well though. Are you sure you got delrin to work?

13

Then try less power and more speed with more passes. You usually need to do multiple passes laser cutting, especially on lower wattage machines.

By the way, I’ve heard that laser cutting ABS produces toxic Styrene gas. I probably wouldn’t laser it any more before making sure.

14

In the lab I work in the vast majority of our CNC’d robot parts are lasercut delrin. So, yeah, it works.

Turn the power down low, do multi-pass if you have to (on 1/4’’ delrin, we usually do 3-4 passes). I don’t know what model lasercutter you have, but I can stop by the lab and tell you the specs on ours and the standard settings for various thicknesses. We can get up to about 1/4’’ thick before the melting starts to get unacceptable for our required precision.

Make sure you have a nice exhaust system set up so you’re not breathing in any of the fumes, though.

15

Delrin cuts nice. ABS smells really bad, and I wouldn’t recommend it for laser cutting.

16

Also of note:

Acrylic cuts the nicest, of the materials I’ve worked with, but it’s brittle and structurally worthless so I wouldn’t recommend building anything out of it.

Polycarb doesn’t work at all, so don’t even try that.

You can lasercut paper to make very nice templates.

17

Never done it, be interested to know how it works out. Kind of came up with it as I was reading this. Suggested it to Team 1997 yesterday when they came to see our laser. As they said “that would be much better than just looking at the drawing and saying ‘that looks about right’ and marking it with a 1/4” thick sharpie."

Agree on that, though make sure you have some ventilation when you cut or engrave anything besides paper (turned our ventilation on the other day as I was about to cut paper, paper went into the ventilation system). If engraving something that’s clear, mirror the image you are engraving, so that when it is facing the right way, that side is smooth. Also, clean stuff such as acrylic, glass, metal (before cermark), etc. before you engrave it. We found out that, by looking at other websites, people suggest Simple Green All-Purpose Cleaner specifically for it. Don’t know why everyone is so specific, but it works well. We use the concentrate at full strength and haven’t had a problem.