Blip wrote:
Looks cool. Would be good to see the print even if a bit damaged. Looks like you were modeling in sketchup (?) How did you find preping the model for printing and what service did you use?
Cheers, this is actually the second model I've had printed the first was a much bigger super heavy scale tank
here. Both were designed in sketchup and printed at shapeways.
Both times I ended up following some advice by Stingray about how to work with skethup, in particular the pluggins he recommends are essential.
Stingray wrote:
Stuff thats good to know;
Its important to work in sketchup at way above mm scale (i go for 1000x the end size). Sketchup has a bunch of weird bugs the make stuff vanish if you work at scales under 1mm. Scale down only at very end.
Watertightness of models (also known as being closed or manifold) is crucial. I found the following 2 sketchup plugins useful for this;
Solid Inspector:
http://forums.sketchucation.com/viewtopic.php?t=30504CADspan (free version):
http://www.cadspan.com/toolsIts probably best to merge all your separate geometry into a single mesh when you export (using 'Outer Shell' or 'Union') but I found this to be incredibly tedious and mostly unnecessary. I saved merging for cases where the preview of the uploaded model looked screwy.
These are the rough steps i follow to get finished model printed;
Check watertightness (probably best to check this regularly during model creation)
Explode all groups and components - more bugs cause the exported models scale to be completely wrong unless its exploded completely before export
Scale down to correct size
Probably want to verify watertightness again
Export in Collada file format (you can also compress it in a zip file for a faster upload)
Upload to shapeways and make sure the 'fix problems'(called something like that) check box is checked. If post upload fixing fails, do some merging/tweaking and try again
Once uploaded go into your 'my designs' area and inspect the uploaded & fixed model with the in browser 3d model viewer. if you see anything screwy then correct/tweak your geometry on your sketchup model, export and upload again
And finally when it all looks good submit for print! (and find something else to keep you busy for several weeks while you wait for it to arrive)
Hope that helps.
In this case I actually had some problems. the first was that when minimising the guns, the bugs which stingray alludes to came into affect and created all kinds of horrible geometry, missing sides and parts of the model to pass through others. It really put me off as I couldn't fix the issue and didn't want to redesign the whole thing so I benched it for a few months. I guess in the intervening time sketchup was updated because I came back to it and it worked first time.
The second was more of an oversight on my part about sticking to the limits of the medium it's being printed in. I'd missed a couple of walls which were less than the 0.3 mm limit for FUD. I got an email from them with a screenshot showing the relevant parts to change and they were really helpful explaining how everything was checked. They did recommend the following as well but I didn't need it in the end.
Quote:
Did you know you can check your model with a free tool called Netfabb,
http://www.netfabb.com/basic.php ?
This program can check your STL/OBJ file, but also fix and rescale the model. You can find more information here.
http://www.shapeways.com/tutorials/how_ ... nd_netfabbWell I guess I've put it off long enough, here's the disaster which is the primed final model. It's about 9mm high and stuck onto a 1p coin, the idea was to try and make it roughly the same height as the old plastic robots. I'm not sure what was up with the primer, perhaps I didn't shake it enough or it was too hot/cold a day?

thanks for the comments guys