Hey all!
I’m preparing a few slides and need help with images for content. If you have images of laser cut wood parts and images of the final part (if the final wasn’t wood) I’d appreciate it!
Solo photos of just laser cut wood or plastic parts are also useful if you have them. Feel free to add a brief description of the part if you’d like.
Thanks!
3739’s 1st intake from 2023
CAD:
Lasercut wood prototype plates:
Assembled wood prototype on practice bot:
Final competition intake (adjusted roller positions after testing with wood prototype):
3739’s 2nd intake from 2023 (went from no CAD to finished prototype in 24hrs after our first competition).
Note that while this prototype was made from lasercut aluminum, it could have just as easily been made from wood (it was just faster for me to get the plates made at my work than to mess around with my small personal laser).
CAD:
Assembled prototype:
Final lexan plates:
Final competition intake:
Screwdriver pins for holding those hooks in position?
I would do the same thing.
Your prototype looks better than many finished robots.
Correct we do that a lot, 5/32" bondhus drivers fit easily through the 0.2" holes.
We do this for maintenance as well, this year we did it a lot to pin our elevator up while working on it.
Here’s the decoration made by my alum team last spring commemorating our prototypes (and near the right, failed designs from the week 1 comp robot).
Lasercut parts up there include:
Competition failed parts include:
)4272 does a ton of laser cut prototype - sometimes making nearly complete versions of our robot. We got our first laser cutter in 2017 and started using it in the 2018 season. We usually eliminate most of the wood in our final version. We build a lot of things with plate/standoffs because of this rapid prototyping technique.
Here are some highlights (just some random pictures on my phone). Some are better than others:
2024
Laser cut Prototype intake.
Final version on the robot:
2023
Off-season elevator project:
Prototype robot:
Final Robot:
2022
Nearly complete Prototype Robot:
Final Robot:
2021:
Laser cut “mini” swerve. Using TTB 1.0 swerve modules
2020:
A prototype custom swerve (this did actually function/drive, but not for very long)
2020 Prototype Robot
Final Robot:
2019
Prototype tank drive:
Practice bot
Final Bot:
2018
Prototype/Practice bot:
Does laser cut metal count?
We are spoiled with the fiber laser so it’s always been easier for us to make high fidelity prototypes out of metal. This is by far my favorite:
And heres one from the shooter from this year:
Is this regular 1/4" ply?
1/4" Baltic Birch is what we use. It’s generally a quality product that behaves predictably when being laser cut.
The issue you’ll fine with regular/generic big box store ply, is the glue/voids between layers varies greatly, and as a result can be extremely challenging to cut nicely and repeatably on a laser.
Is the white material polycarb or Acetal (delrin)? Ive laser cut Acetal, but my understanding is that polycarb will burn and give off nasty fumes. But I’ve never tried it
It’s polycarb, polycarb off gases benzene which is bad for you but not chlorine gas levels of bad for you like with cutting any vinyl or PVC. (Wood smoke is also not good for you in large quantities either). We have a very over spec’ed dust collector extracting all fumes out of our laser cutter. The polycarb smoke is bad for the laser optics so most places won’t cut it for you as it shortens the life span of the lens and mirrors but again with enough exhaust and air assist and always cutting through in one pass to ensure you get good fume extraction that damage can be mitigated, we also aren’t cutting in a production environment just for the team so it’s running much less than a laser shop would.
Good to know. Ive tried HDPE (with no luck) and wood on my epilog laser. But never tried ploycarb. Ive just heard that you couldn’t cut polycarb so i never tried it. Ill give it a shot and see what happens. We also have a very good exhaust system so it should hopefully be ok
Haha sorry, while our team has external access to a Trumpf fiber laser, I am hoping to stick to examples of just things most teams can make on 100-130W co2 lasers 
Could you share more information on the laser and dust collector that Spectrum uses? Or perhaps link to any previously documented information?
Also curious - where are most of you buying your Baltic birch from? I feel like I’ve only rarely seen it at large home supply stores.
Cheapest supplier?
Most of our prototypes are cut from 5mm underlayment from home depot, it’s the cheapest stuff we can find and it cuts reasonably well.
We do use 1/4" birch for some things, we buy it from a local hardwood place (Clark’s Hardwood in Houston).
The laser is a Thunder Laser Nova 100W 600x900mm, if we did it again we’d get the 130w 900,x1200mm version. Some companies are selling 150w CO2 lasers now that may be even better. The laser has its exhaust fan that is ducted to the dust collector and both are running while we cut.
You could totally make the above prototypes from wood or acrylic.
Our first turret prototype was actually bearing-less and just slid around on itself, but we added the bearings to the second iteration to test the whole thing while moving around at high speeds.
