On Thu, May 25, 2017 at 1:33 AM, Forest Crossman cyrozap@gmail.com wrote:
Hi, all,
The recent update on Crowd Supply (regarding the difficulty in mass-producing parts with 3D printers) reminded me of some RepRap/RepStrap innovations from a few years back:
oo interesting
https://web.archive.org/web/20150318000301/http://justindunham.net/making-ca...
hmm, currently offline (as in *archive.org* is offline!)
http://reprap.org/wiki/Clonedel http://reprap.org/wiki/Moldmaking_Tutorial
ooo niice. very clear. i like it.... except that the resins are listed as not being as strong as ABS (which i've tried and it failed miserable) and not quiiite as stiff as PLA.
now, unnnfortunately, the design of the laptop, whilst it is quite light (1kg) really is rather long - 230mm deep and 330mm wide - which means that it's relying on the stiffness of PLA (and the PCBs) for its structural strength.
i didn't realise at the time when i said i'd provide a DLP option that resins are not as stiff (and a lot more brittle) than PLA, so that one's going to need some thinking about / research, hum...
This was before cheap, mass-produced 3D printers became widely available, so many people were bootstrapping their RepRaps by purchasing 3D-printed parts from others. At some point, someone realized that it was a lot faster to 3D print a set of parts, make molds from them, and then use those molds to make additional part sets, than it was to separately print each set of parts.
I'm not sure how complicated the parts of the laptop case are,
pretty complicated but also designed to be injection-molded. it *should* be doable... but resins i think might not cut it.
but if the parts could be re-designed to be optimized for resin casting, it might cut down on the production time. Of course, I've never done any resin casting before so I don't know how feasible this would be in practice. Also, I have no idea how fast modern 3D printers can run now, so the speed advantage might not even exist any more.
well the $150+$40 shipping truly dreadful taobao-knockoff i just finally managed to get up and running after three WEEKS of redesigning its parts, is currently running at an amazing 150mm/sec with only minimal degradation in quality: bulging at sharp-turn (90 and 180 degree) corners.
which i am kinda blown away by. but... then again... i _did_ totally replace the entire x-end and carriage mechanism with a horizontal arrangement, put a 50mm triangle in one strategic corner of the frame (only one so far), replace the glass+MK2 printbed PCB with printbite + a MK3 aluminium 3mm plate....
none of which will really dramatically increase the cost so is a positive sign.
Anyways, I just though I'd mention this on the off chance it might help speed things along.
appreciated. do you also have a 3D printer and would you (or anyone else) like to give this a shot, see what happens? i'd be interested to know how much "bend" there is in the back base part and the left end part for example.
l.