I need to hack a 3D printer together so I can make prototype bearingless Simpson's on the cheap.
3D printer part quote:
This past weekend I got a quote for the upper arm using makeXYZ.com. It was way too expensive for the scope of this project. So I redesigned the arm, and shaved off 90 cm3, and reduced the cost to $45.00, it's probably still too volumetric (fat). Everything needs to be redesigned to reduce unused volume as much as possible. I determined today that shelling is not an option (hollow), shame as there is a massive reduction of part volume. I could get the cost down to $13.00, but impossible to print. Fyi the total cost was $522, not counting electronics, the chunky arms need to slim down :)
I still have a lot of little details that I need to think about, and make decisions on for the given geometry that I'm working with. I'm excited to work out the varied details, and build a working bearingless Simpson model.
In fill volume cost reduction:
One idea to solve the problem of not being able to print a shelled part is to print 'strategically' placed tiny pins closely spaced, and orientated (some regions of the shelled area would have support others would not have support). Hollow parts need some way to bridge large gaps, and the pins provide that bridging support. Not having a printer I can't test this idea today, but I'm curious what the spacing would be?
The reason a pin is desirable over infill is to get a lower price quote from people who own 3D printers. It appears that the 3D print shops don't care how much material that I'm using, only the volume of the part, shelling reduces the volume thus my cost.
Electrical:
I'm still studying the electronics that work with the Repetier firmware. I like the Azteeg X3, but there are a few others in the same price range that look interesting as well. To reduce my learning curve I want to keep it simple, and the electronics integrated as much as possible. So I'm more interested in the higher end boards (I'm assuming they are easier to get setup and running? i.e. shorter learning curve.). The ARM 32 bit microcontroller appears to be the newest technology, and maybe it's easier to use? I've not run across anyone using ARM with the Repetier firmware (I don't know where to look for examples).
Jumbo Simpson:
I have about 4 pages of notes for a jumbo Simpson 3D printer, with lots of ideas on bed leveling across large spans, etc (FYI I've leveled boring mills to .0005 inch over 10 feet). I've been noodling ideas on this for the past year. But it's not a practical machine for me at this time to begin developing. What I need today is one small desktop printer, and one large printer with about a 1 meter envelope. After I make the two smaller printers, I'll be able to work on my larger product designs, and a larger printer. You should start the thread, as you're already moving it forward.
A2