3d printing robot components

[praveen_khm]

Hi,

I was watching a video on 3D printing. Wondering how strong is it for robots. Has anyone before used it? If yes, how strong will it be if I consider it for gears? And any idea on cost incurred for that?

Thanks

[Cyntrox]

There's a small post about it here.

They sell that printer for 1999 pounds (about 3250 dollars).

[praveen_khm]

Thanks for the cost. But has someone used this before? Especially for gears? I need this for custom designed gears and those available in the market do not fit my requirements. If they are really sturdy, I guess I will go for shapeways or a similar kind to get it printed for me.

[garrettg84]

Build a 3d printer yourself. Check out reprap, you should be able to get a decent one together for $500USD. It will likely even cost less if you cannibalize some robotics parts =)

http://reprap.org/

The accuracy of a reprap is as good as you decide to make it. The hardness of the materials depends on what you use, but ABS plastic is one of the common ones and it is pretty sturdy. I wouldn't imagine you'd want to use printed abs gears for a long time in a bot, but for prototyping and development it is awesome.

reprap made gears...they aren't perfect, but they work

RepRap making gears

I am building a reprap right now after seeing them in action at a few of nerd conferences I've been to lately. One other bit about the reprap, it is to some extent a self reproducing machine - that's the idea anyways. People have been building them with tighter and tighter tolerances as they continue to rebuild their machine using parts it creates!

[praveen_khm]

Build a 3d printer yourself. Check out reprap, you should be able to get a decent one together for $500USD

I was looking at that option too. Past 2 days, trying to figure out things in their wiki;

but for prototyping and development it is awesome.

Ofcourse they are for prototyping. Actually, I am trying to add a couple of tutorials on my site www.robotplatform.com and checking out few options before I start anything.

I am building a reprap right now after seeing them in action at a few of nerd conferences I've been to lately

Thatz awesome. Are you using a kit, or is it that you start everything from scratch? If you are starting from scratch, please let me know how easier or difficult it is, so that I can try making one.

[garrettg84]

We are building one from scratch. I mentor a highschool robotics club and we are putting one together so we can do custom parts for competitions.

[praveen_khm]

That is interesting. Hope to see how it works.

[hazzer123]

We've been using our RepRap for around a year now to print robot parts. So far its main use has been for little things, like sensor holders and various brackets, although that's just because the majority of our club's members aren't too knowledgable about 3D CAD.

A good example of the real potential of the RepRap is in the Quadracopter one of our members made. The chassis was fully 3D printed (designed in Google Sketchup). It was flying just 2 weeks after starting to design it!

We've got two RepRaps now (the 2nd one is a Prusa and was printed on our 1st one) We'll  teach our members more next year about how to use it so even cooler stuff can be made in the future!

[praveen_khm]

We've been using our RepRap for around a year now to print robot parts

Thatz a nice one. With so many people building their own RepRap, I guess I should try making one. The initial fear is what pulling me back.

BTW, the Quadracopter looks cool. What about rotors? They look like carbon fiber ones.

[Admin]

Gears must be very smooth to get any decent efficiency out of them. The cheapo 3D printers like RipRap won't get you the smoothness you want.

All 3D printers have a minimum layer thickness, causing small gears to be very poor in quality. Large gears will work much better, due to the accuracy ratio.

You can get a company to print you gears for ~$100 with high quality printers, but thats more than the cost of just buying actual gears. Spending $500 on a cheapo 3D printer and having to learn it is another whole can of worms.

I'd recommend here first:
http://www.smallparts.com/s/16412081/ref=sp_s_sg_16412081?prevKeywords=gears

[hazzer123]

Yeah that's very true. Gears on repraps aren't great. Not really because of the layer thickness, but the the thickness of the plastic filament. This puts a pretty low upper bound on quality of intricate details such as those required by small gears.

We usually get our gears laser cut from acrylic or buy them. Laser cutting gears has the disadvantage that the beam diverges when passing through the material so you often get tapered edges, but, on the plus side, you can make them any shape/size you want. You can even go crazy with eccentric gears like these
[youtube]

Unusual gears

[/youtube]
But obviously they don't have great efficiency

BTW, the Quadracopter looks cool. What about rotors? They look like carbon fiber ones.

The chassis is 100% 3D printed but the rotors aren't. They're just standard cheap plastic ones for RC helis. We've stuck a few more videos on if you are interested - Quadrocopter Wiki page

[praveen_khm]

I'd recommend here first:
http://www.smallparts.com/s/16412081/ref=sp_s_sg_16412081?prevKeywords=gears

Thanks admin. I found few nice gear sets in a local electronics shop to serve my purpose. But just that when I see the 3d printing ads, they tempt me to accept that they are good. 

We've stuck a few more videos on if you are interested - Quadrocopter Wiki page

Sure will check them...

[Razor Concepts]

I think a laser cutter would be a lot more effective in general than a 3d printer.

[garrettg84]

I think a laser cutter would be a lot more effective in general than a 3d printer.

Only a laser cutter cant really cut the inner space out of a hollow object. If you needed an object with 'relatively' complicated inner structure, a laser cutter wouldn't be the way to go unless you were interested in cutting sections of your final product and gluing them together.

[arrrrgon]

Btw, you can buy a pre-built reprap off of ebay most days if you don't want to build one yourself.

[blackbeard]

something to think about when thinking about reprap is that the really fine parts you see are either on repraps with custom parts and/or hours of tweaking. it's certainly a great opportunity for advanced robotic builders. a group at my college is getting one and are storing it in the same room as the electronics lab i have access to so as long as it's not guarded

[garrettg84]

Speaking of 3d printing

http://www.thingiverse.com/thing:4673

That is the RepRap 'motherboard' and all additional boards for controlling extruder, motor controllers, and heating element. You can do these boards at home by etching with your preferred method (UV, Mill, Laser printer). My group of highschoolers are about 75% done building their rep-rap (its taken 4 weeks at about 2 hrs a week) and we should be done by next week. I'll be giving these home made boards a shot once we get our school project finished up and let you guys know how it turns out.

[Asellith]

shapeways.com and ponoko.com both offer 3D printing at reasonable prices. I use ponoko for all my laser cutting. I'm cutting $300 - $600 a month now. I don't have the capital to invest in my own but at ponoko's prime price it is really hard to justify the big capital expense. I have not ordered any 3D printed stuff but I have seen some ship models that look great. They are expensive but the cheap strong and flexible stuff shapeways prints in would work for gears.