Darwin 2.0 - pics inside.

Seeing that everyone's forgotten about it, I invested some time into compiling a new design. My goal is to incorporate an ultimaker style gantry into a new style Darwin while using the 'bare-bones' attitude of the prusa.

Here's what I've come up with so far. It only exists within solidworks at the moment, I've printed a few pieces but haven't assembled or tested anything yet.

I'd really like to eliminate belts all together. I knew they're cheap and fast, but I dislike adjusting them all the time. Most professional grade cnc equipment works on leadscrew or ballscrew. I'd like to incorporate that into this design.

Here are a few angles of the assembly.

Interesting. But first, please turn off your origins next time. I've been thinking for some time that Ultimaker's gantry on a rods and vertices frame would be an interesting design. I hope it turns out well.

I'm guessing the yellow rods are smooth, right? Will the build platform be guided on the vertical yellow rods? I'm thinking they must be, otherwise the Z axis screws will create a wobble problem. It might be a simpler build if the platform is supported and guided from one side rather than supporting it in the center of two edges and guiding it at four corners. I know the TOM does this, and I think the Ultimaker does too.

I think I see some problems though. Driving the X and Y axes with screws is going to be very slow, unless you spend some money to get high-pitch lead screws. I also don't see that the X and Y yellow rods are guided by anything other than the screws that move them. Ordinary threaded rod is going to have some wobble in it, which is going to kill Z axis and layer thickness accuracy. If you use quality high-pitch screws, that might be better, but it still won't be as good as guiding on smooth rods. Also, the harder you accelerate that, the more bing you'll get do to the loads being offset from the screws. I just don't thinks this will work out better than belts. If you've had problems with having to adjust belts, I'd suggest improving belt designs instead.

Yes that's the one caveat of the design. A requirement would be spending $ on the leadscrew. I've found some promising stuff at mcmaster carr.

6350K12 - fast travel multiple start 1" per revolution. Cost is $132 per 6ft, but would be enough to do 2 printers.

The plus side though, it would last the lifetime of the machine.

keep us posted!

I posted some files up here - [github.com]

Still learning the whole github process yet...

Heh. For me, Github's learning curve seems twice as steep as RepRap. Probably not nearly as high though.

Let us know how those screws work out.

too much stepper motor (my opinion)