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You. Are. My. Hero.

This is one of those projects that's been itching away at the back of my mind, but always on the backburner. Having a starting point will be a great help getting things rolling.

How much did it cost you, all in? And how do you find a laser for cutting some of the more technical fabrics? (Specifically thinking of some of the ultralightweight fabrics the MYOG community loves to nerd out on.)

Wonderful!

I disassembled an old 3D printer for the stepper motors and control board. But I would say it probably costs in the neighborhood of $300-$350 to build from scratch. I spent under $200 since I had a lot of parts already.

I've not tried cutting those technical fabrics! I would suspect it works fine. I am mostly making street clothing with it. I've cut some medium weight polyester with no problem, but haven't tried super light stuff. The laser power is adjustable so I suspect it will work fine.

Also I have a full config file for the 3d printer control board. If you get the thing built PLEASE ask me for that in a github issue as I do really need to add it to this repo.

Perfect! Thank you so much.

Is there any particular reason why you chose that specific laser model? I'm not very knowledgeable of the technical aspects of lasers/laser cutting, but would love to learn more.

I saw a YouTube video of someone talking about an earlier model of that laser and it looked nice! Also had the correct PWM input for control from my 3D printer control board.

I love the motion mechanisms; the tension bearings on the rail remind me of the V1 MPCNC designs and the rope gantry system reminds me of the Kralyn3d Positron.

Please consider throwing up your files on github entirely. OnShape has a login-wall, even if it has free account options. GitHub even supports native STL viewing!

> the rope gantry system reminds me of the Kralyn3d Positron.

I still had a spool of high stiffness line that I bought back when people were experimenting with that! It was one of the early delta printer variants, like the Kossel or similar that I first saw that working. It took a little while to prototype the spool winding system but in the end it works really nicely! Its just so light and cheap, I love it.

I should throw the STL files up. It was a big rush to get the project finished and I had a lot of other stuff to focus on. And I do want to encourage people to dig in to the design and make forks with their changes. But it does work pretty well as is, so STLs would be helpful. I also accept pull requests! I am super busy and pleasure projects like this are so hard to fully document.

I appreciate the kind words!

This is absolutely amazing. As someone that spends ungodly amounts of money on outdoor gear, I'll be digging into this tonight after work.

Thank you!

Yay!! I can tell you it is SO nice to have repeatable patterns that are so easy to cut. You just lay out all your fabric flat, hit cut, and sit outside with a drink while everything cuts. A large pattern with thick fabric can take ten minutes, but you’re just watching as it happens.

I do sometimes have stuck stepper motors. That leads to messed up cuts and it’s one reason I want other people to reproduce the design and add their own tweaks. It generally works, but I would like to see the sticking of the Y axis improved.

I just realized that I have some stepper motors in a box from an old robotics project I did. I'm going to attempt this next week.

Awesome! Important to note that I used smaller steppers that the most common size. I have a link in the GitHub docs to the steppers I used. If you’re up for a mechanical design project you could modify the design for your size of steppers. I think it could benefit from a little more torque on the Y axis TBH. But maybe I can increase the drive current in software without issue, I’ve not tested the limits of that. Anyway it would be useful to try larger steppers as I’m fighting an issue of Y axis sticking occasionally which is very annoying. And I bet a lot of people would appreciate the design work. I’m pretty busy in life but I could try to provide a little help if you get stuck. Just open a GitHub issue and we can connect more directly as needed. I hope you do give it a shot one way or another! The motors I used are cheap on eBay if you want to go that route. I harvested mine from a cheap mini delta printer I wasn’t using.

Coming from a scientific/laser safety background here... How does a system like this prevent loss of control of a beam?

In a university setting, I would guess that a completely open system like this would only be permitted if interlocks guaranteed that the laser head was unpowered unless everyone was out of the (windowless) room.

The space-saving/rug trick is awesome.

Yes, what if the head got mechanically stuck somehow, and the force of the motors forced it out of position, pointing it in a random direction?

Well the stepper motors aren’t very strong, so if there is any obstruction it will just stop moving. But the laser head itself is very securely mounted to the carriage, which is very securely mounted to the gantry. I guess it’s possible the gantry could tip, though I’ve never seen that. Otherwise I don’t expect the laser would ever really change orientation. Someone could do some testing to see how hard it would be to tip the gantry. But again, the stepper motors aren’t very powerful. And I’ve accidentally kicked the gantry when forgetting to step over it and it stayed seated.

Also you can make the gantry runners arbitrarily wide, at the loss of some Y axis travel. But you can also make the Y axis arbitrarily long. So if you have space to extend things, you could make the gantry runners wider to give it even more stability against tipping. (A problem I have so far never observed)

I did have a chat at lunch one time with an optics engineer about high powered lasers and it scared the shit out of me for life. That said I’m not operating with any institutional concerns. I personally have a lot of experience with dangerous machinery like CNC machines, plasma cutters, welding, etc. And I don’t have kids or pets or roommates to worry about. So I use good judgment and wear laser safety goggles.

The laser itself has a 5mm focal distance and the housing is rectangular with something like a 40mm square footprint. This means that you can’t directly see the spot it creates, and this seems to help a lot. It’s mechanically very solid so I don’t expect it to tip over. It is also poorly columnated such that it diverges pretty quickly when not pointed at a target.

All this works fine for me at home, but I suspect a university would need more safety structure around it.

Goggles are an important first step -- if the wavelength is long-enough, you can sometimes get away with quite-inexpensive goggles.

The short focal length helps, but you're starting with a lot of power. Careful with specular reflections, especially off of concave objects that might refocus the beam.

The hard part with these things are that the beams are invisible and the damage (especially at near-visible wavelengths) can be instant without a lot of power.

Yes, all good advice thank you! Luckily there is no metal underneath the mechanism or in the fabric I cut, so that reduces the likelihood of specular reflection. But thanks for the tips.

Oh this is incredible! As someone who absolutely hates the cutting part of sewing I'll be adding this to the top of my to do list!!

hi this project sounds great! I've been wanting a large format plotter to help with designing and making patterns. I use a cricut today for small projects. Vinyl cutters are also an option but the cheap ones have terrible software. A combo pen plotter for 36" paper and a larger laser cutter for fabric sounds ideal if one has the space! I'll def read more about your project.

Awesome! Is there anything stopping using this for wood too? Any problems with vibrations messing with the cuts (like from walking around it)?

My floor is concrete so it doesn’t vibrate. But I’d say this should work with wood just fine! I do use wood for the backing so you’d have to be mindful not to cut through that.

Thank you for sharing this. In terms of common garment fabrics, what kind of fabrics can't be laser cut.

I haven't done a lot of laser cutting, but I expect there will be a ranking that is basically this from best to worst:

synthetic fibers > plant fibers > animal fibers

I will also guess that more shiny is more bad.

Edit: while on the topic of animal fibers, one fabric that gets way too little love in the outdoors community is wadmal. If you are doing anything that has intervals of high and low activity and you tend to sweat, it beats any GoreTex (incl. Pro versions) hands down for keeping you dry. Unless you are out in heavy rain for prolonged periods, in which case the only thing that keeps you dry is the thick PVC stuff that fishermen use.

Thick white material is the toughest. Like thick white denim or canvas requires a very slow cutting speed. Polyester seems to emit some kind of harmful gasses. I always ventilate the room, wear an n95 mask, run a HEPA filter nearby, and sit outside during and shortly after cutting pretty much anything, but especially polyester. I can't really think of what would not be cut by the laser, but I don't know anything about what fumes may be more or less harmful.

Yeah, there's certain materials that the laser cutting community knows about that you just don't cut with a laser. One of the gasses produced is Hydrogen Cyanide Gas (HCN). PVC also produces nasty gas as well.

Here's a more definitive list:

https://laseruser.com/what-can-a-laser-cutter-cut/

Ah good, polyester is okay! I mean, definitely do not breathe whatever it's putting out. The first time I cut it I did not wear a mask and my throat was immediately very sore.

I think an organic vapor respirator is warranted but it's been a while since my training. Generally an N95 is for solid particle IIRC.

Yeah makes sense! These days I basically just step outside while it’s cutting and let the room air out for a while before I return. I do have to check on it to make sure it hasn’t had an issue and for that I wear a mask but also basically hold my breath and then hop outside again as soon as I can.

This is a cool project. I wonder swapping the laser for a sharpie/pen plotter would make it more accessible to a wider audience? I imagine that you could cut it accurately enough if the designs were drawn onto the fabric?

Perhaps! But the drag of the pen would likely move lighter fabrics, and if it catches at all it would bunch up and surely drag the fabric all over. Maybe there is some way around that, but for me once I’ve gone to all the trouble to build a full motion gantry and control system I’d spend the additional $100 to include the laser and get the cuts done as it moves.

Could it tape seams for waterproofing?

This Solar LED umbrella could be a different fabric than cotton.

Just picked up a few tarps with a bunch of loops all around the sides and through the center for guidelines.

TIL hemp is antimicrobial and it can be mixed with {rayon,}.

Hmm I don’t know! That would be a great thing to experiment with!

This is amazing. Could fabric welding be built off of this?

Fabric welding ?

Probably referring to polymer ultrasonic welding, or less likely polymer thermal bonding. From experience I can tell you that ultrasonic welding is relatively complex in that it generally requires a shoe on the upper and lower side of the two pieces of fabric, correct pressure, correct ultrasonic frequency, and either (A) both pieces need to be held steady and the head must move; or (B) vice versa. It's not a process that is easy to replicate for complex geometries or novel materials and applications without significant preparation, jigs and fixtures. This is in direct contrast to cutting or marking where a head can simply glide over a flat material and effect a two dimensional geometry. https://en.wikipedia.org/wiki/Ultrasonic_welding

I don’t know! I’m not familiar with that process. Do you think conceptually it would work? What would be the issues?

You wouldn't happen to be friends with Windell & Lenore, would you? ;)

Not that I’m aware of!

https://shop.evilmadscientist.com

Oooh they are local! I have very likely bumped in to them at Maker Faires and other local events.

Very interesting. Is there a way to do it without printing a lot of rails.

Great question! I’ve not spent much time thinking about that but I imagine there are alternatives.