After reading this really wonderful Instructable by a kid my age who just wanted a cheaper laser cutter, I started to think about designing and constructing my own. I would want at least 100 Watts (I think) instead of his 40 which I imagine would be a fairly simple upgrade. I’d also want a larger build area.
My question for you, FRC community, is do you think this is a good plan? My team, the Cyborg Cats, may have a sponsor willing to donate some high enough (and then some) quality stepper motors. Do any teams have experience building their own? It can’t be too much harder than the CNC router 971 built themselves (not that that looked easy), right? I think I could save a few thousand dollars going the DIY route. His final build was around $2400, so ideally I could make a 100 watt version for around $5000. Buying a comparable laser could cost over $10000.
Note: this would definitely be next offseason’s project so I have time to make a decision.
Do you really need 100 Watts? I do 1/8" acrylic on a 30 Watt tube. What do you want to cut or engrave? Here is a 50W laser that would likely be much better than one you could build on your own, and it’s $4,000. For another $250 you can go to 65W. I have a Boss Laser LS-1630 with a 100W tube and I’m quite happy with it for the price.
There’s not much difference between 60W and 100W in FRC IMO. The 40W and 60W lasers at SCU can cut both reasonably quickly. More power is only useful if you get like 2kw to cut steel IMO. $5k does seem like a bit much for a DIY laser build though…
That being said, if you have the budget 100W is doable. Laser cutters don’t have the rigidity requirements that routers do so that makes it easier. Just make sure you add an enclosure so nobody slices their hands off on an invisible beam.
This looks like a very good base to start off of, but if you’re planning to cut plastics I would definitely recommend a stronger filter than the one that the instructable uses. The ones I typically use have a separate unit just for filtering the air before venting it out, and one even goes so far as to vent the filtered air to the outdoors. Try building something like this or this to handle the fumes and you’ll be a lot safer.
Between fall 2016 and summer 2017 Triple Helix built a DIY 80 watt laser using lessons we learned from rebuilding a smaller 40W one we acquired.
Attaching photos and BOM.
If we were to do it again, we’d:
– Make a painted welded steel frame rather than one assembled from 8020.
– Choose less expensive steppers and stepper drivers rather than using servos. In the near future we might transplant these servos onto a router table.
Just remember that if you build or buy a laser cutter you’ll have upkeep costs. Such as replacing optics and the laser assembly if it fails.
I have a Jameson laser cutter with a power Z axis that can handle a rotary table (I picked it against the Boss Laser and APLaser model in part because Jameson stocks parts in CT, I could test it at pickup, it actually fit through my doorways and it runs on a bone stock 110VAC 20A electrical service). The first year warranty covers the tube if it fails. After that you are looking at several hundred dollars per tube.
My 60W setup with chiller was a little under $7,000.
I was thinking 100 Watts so I could cut up to 1/2 inch plywood and at least 1/4 inch delrin or ABS quickly. I remember reading somewhere 150 Watts can do 1/8 inch aluminum, so that might be something to look at. I mainly wanted to know if this was actually a feasible idea I should pursue in order to save some money. A large build area is very attractive to me so any Boss Laser would have to be at least a 1630, and preferably bigger. I’d design it to be at least 36 x 48 if I go that route. $5000 was kind of the cap I was looking at obviously I could go cheaper.
This is not accurate information. The laser cutters of the type being discussed here (Self-contained CO2 engraver-style machines similar to those produced by ULS, Trotec, Epilog, etc. with no cutting gas or anything fancy like that) will not cut any metal useful for FRC applications – potentially only very, very thin steel. Aluminum is harder to cut than steel with a laser because it is more reflective – you need either a fiber laser, or a full size industrial CO2 laser with at least an order of magnitude more power. When we did sheet metal our sponsor had a 2500 watt CO2 laser, and I believe 1/4" aluminum was their stated upper limit – we never did thicker than 1/8".
You can’t cut aluminum with a 100 watt CO2 laser especially 1/8 inch. Aluminum cutting lasers have very specific tuned frequencies to cut it properly and most are high power AC CO2 lasers with powers in the 4kw range just to cut 1/4 inch aluminum. So the low power 100W dc laser that you would have access to and be using in this cutter couldn’t even touch aluminum. It is just so difficult to cut with its insane heat dissipation and light reflection even when liquid that makes it near impossible too cut with a laser.
None of those vendors’ CO2 tubes will even cut thin steel. Trotec offers a fiber laser option that will cut thin steel, but you need a 2+ kW CO2 with assist gas/fiber laser to seriously cut metal.
When you say 1/2" ply, do you mean 9 ply Baltic Birch, 5 ply Spruce Sheathing, or something else? Do you cut that thick in a single pass or multiple?
I have read that the cutting capability is very dependant on the stock (especially the glue). I’ve also been told that not all CO2 lasers are created equally, and that a cutting edge 80W will outperform a 100W+ bargain tube, but I have no data to back that up.
(We’re taking delivery of a 120W CO2 laser tonight! - nothing like last minute arrivals)
Here’s a video our team made last year. We used a sponsor’s industrial fiber optic laser. Some of the things we learned was by designing the parts using the same thickness we could nest all the parts onto one sheet of material. The laser cut holes are precise in relation to hole to hole spacing and size.
Going from CAD design to laser cut part was very simple with the right CAD training and software tools.
Note that while these smaller lasers won’t cut aluminum, they can make the job of laying out parts to be cut much easier. We experimented a bit with this over the summer and developed a process. In about 2 weeks I can let you know how it goes.
We tend not to have time for making drawings (we also don’t have a printer), so to get designs to the shop, we’d make quick, dimensioned hand sketches. Students would use layout tools to mark cut lines and hole locations on parts, before making the parts on bandsaw and drill press. This process is error prone, and often the finished part just didn’t work for one reason or another.
Now, if the part is up to 1/4" thick lexan or delrin, CAD can make a quick drawing view, export as a dxf, copy to thumb drive, and hand off to laser cutter operator. These parts are directly cut to size. If the part is 1/8" aluminum, we follow the same process, except that the aluminum gets a thin coat of Dykum blue layout ink. The laser won’t cut through the aluminum, but it does a nice job of etching cut lines and hole locations in the blue ink. Then the marked out material can go to the shop for hole drilling and perimeter cutting. This eliminates the error prone steps of creating a sketch and laying out the part. Cutting down wasted rework time means more time spent iterating on scoring mechanisms.
Lexan (polycarbonate) will make chlorine gas which in addition to being not so good for you as the operators is prone to do damage to the assemblies over time.
Acrylic cuts very nicely be it extruded or cast.
Several laser cutter makers list Delrin (acetal) as workable just make sure to vent any formaldehyde you might release. Less you like to be well preserved ;).
You can laser cut ABS but it will stink.
You should not laser cut PVC or vinyl - again chlorine gas.
HDPE and Nylon melts a little too fast when you try it…but if you can keep that under control it can be done.
Styrene and foam works but you want ventilation.
Teflon (PFTE) can be laser cut.
Non-chorinated rubbers - again be careful of chlorine.
Fiberglass and DuPont Corian (if you can get Corian and you will use 80W or more to do it) can be laser cut.