Help! I can’t get openscad to build a manifold version of the ubiquitous triffid hunter parametric herringbone gears. I’m using the default file with 3 changes - distance_between_axles 40, small gear has 11 teeth, big gear has 44 teeth. I’ve been fiddling various parameters to try to find whatever is causing the error but with no joy :(. Anyone able to assist? Ideally just by giving me a manifold STL with the above changes.
http://www.thingiverse.com/thing:10707
Try http://cloud.netfabb.com/ and see if that’ll fix it.
Ah but you see, openscad won’t let you export a non manifold stl 
Then you’ve got a face that’s touching somewhere. 
Here ya go: https://docs.google.com/file/d/0ByxvvRr2A-puNDVDTDJWeHRNdms/edit?usp=sharing
I changed the distance to 39.99 and it seems to have worked in exporting an STL for me. 11 on small gear, 44 on large. Let me know if I screwed anything up.
@ThantiK awesome! Cheers mate. I did lower the distance to a non integer (39.5) but clearly I should have been more granular. Much appreciated. @Paolo_Amboni I need a 1/4 ratio for the belt driven z stage - with a 32 tooth gt2 pulley it gives 0.1mm per full step and all kinds of nice sub .1mm microstepping
@Tim_Rastall , no problem. Glad I could help. Make sure you have the MCAD library installed and try to replicate what I did. If you still can’t get a manifold STL to export it might be some sort of configuration problem on your machine?
@ThantiK cheers, tried it on MacBook and windows 7 with same result. Didn’t have mcad installed though.
Aha, that’s 1 option. The other is for a twin belt driven solution that doesn’t require a $30-40 lead screw and gives better Z resolution (becaue of the gearing). I’m just finalising the design then I’ll post some renders. Should have a prototype built over the next week.
if you can wait 2 weeks for delivery, get it from China: http://www.aliexpress.com/item/industrial-aluminium-square-20x20mm-wholesale-aluminium-profile/542747952.html
Yikes, $90 for 3ft of the stuff? Holy moly.
@ThantiK look again, 6m for 90 including shipping.
OH, 6 pieces of 1 meter long! Doh! Would 1 order of this cover the size you made your upscaled tantillus?
Ah, not quite. It just covers the frame. You need an extra 2m for the z stage and build plate. I have some spare bits so one order was fine. Generally I just message the supplier and got them to list a larger order. In the states you can probably just get it straight from misumi or eBay for the same $/m