Hi Michael ...

I'm trying to upload a file to Shapeways (solid printing). MoI tells me it is a solid before I export it but Shapeways reports it to have non manifold errors.

Any ideas?

cheers,
eric

ps ... shapeways requires .stl files

Hi eric, could you send me the file (through e-mail at moi@moi3d.com if you want to keep it private) so I can take a look?

You may want to not make an excessively heavy mesh, if the mesh vertices are too close to one another it could possibly cause problems.

- Michael

It is not any more than an experiment so here it is. Both files

Hi eric, do you have a multi-core machine?

I think that you may have run into a multi-threading meshing bug in the current v2 beta, I've e-mailed a patch to you so you can try it and see if it solves the problem.

The multi-threading bug could occasionally cause one edge of the solid to improperly have a lot of extra points on it, just on one surface's side so making the mesh non-solid.

That appears to be what has happened to this particular STL export.

- Michael

Hi Eric,
You can actually have the Lamp work "as is" for uploading to shapeways:




What you will need to do is just before you create your stl, switch the system units to "Millimeters" then export your stl and upload it to shapeways.

Shapeways servers run and convert everything in Meters and the issue with inches is prevalent. You can do the conversion without affecting anything about the size and quality of your model.

Burr

Hi Michael ...

Yes, I do have a multi-threading machine. The patch worked.

Burr ... I took your advice and changed to millimeters but by itself it didn't work ... as soon as I placed the patch everything went clean and perfect.

thanks to you both.
eric

There is a catch 22.

$1,600 is a pretty expensive transparent plastic lampshade ... 3d printing is not the best answer for this idea.

While I was playing I made a model of another lampshade that I can make with light weight poster board or even heavy bond paper for a cost of about $6.00 ... more within my budget.

I am intrigued with the idea of 3d printing and the next time I take a few hours off to play I think I will design something small, like a pendant or a napkin holder.

It was a good learning experience, though and again thanks to Michael and Burr for their help ... so fast, too.

cheers,
eric

Hi eric, I'm glad the patch solved the problem.

But yeah it is not very economical to rapid prototype something more than 1 foot tall.

Something more like 4 or 5 inches in size is more like it...

For something smaller like that, shapeways seems to have really good prices, even down to something like $20 or so which is pretty amazing (this kind of stuff used to cost several hundred dollars minimum). But the price must go up steeply once you get over a certain size.

- Michael

Hi Michael ..

Now that I can make things this way that work I'm full of ideas ... buildings take so long to reach the real end results (and often never do). I have always wanted to be a potter and see results immediately but my hands did not cooperate well enough. This 3d printing gives me another chance to use the tools of my trade to make small things with a lot of design possibilities.

Thanks again for MoI and the patch.

cheers,
eric

The other thing to remember with them is they charge by "Volume of material used to print it", not size of bounding box. So if you make a simple sphere, it can cost alot more than if you boolean out the middle of the sphere and make it hollow. With the bounding box size, the only limit becomes what material you can print. At it's (the lamps) default 42 cm tall, their only machine and material is the stainless steel option at 1300+ dollars. To get the white stuff it has to be within a certain dimension (listed on their page). If you shrink your model down to be able to accept the white material, the price would go from 1300 to about 100. The transparent would be about 250-300. The price of the materials that reflect these numbers is $10 stainless steel, 1.50 white and 2.77 for the transparent.

Not very feasable for the lamp object though, But, if you wanted the transparent lamp shade, you could try and "Hollow out" the walls of the solid, then re-upload it in the dimensions allowed for that material and see how much the price drops. The hollow may make a nice effect if you can get the price to be around 50-75 bucks or so.

As for the unit conversion not working, I did have it set to scale on unit change also. But it sounds like Michael has found somethoing else going on there. It worked for me, but I was only using a P4 to do the file.

Anyway, Good luck.

Hi Michael ...

I'm still having problems with this. I reduced the size and rebuilt the model ... after some fussing with booleans I finally had a solid and it did upload to shapeways after a failure and then increasing the number of polygons for export (by about 20%).

THe cost did came down substantially (but not enough) so I decided to scale it down further to the minimum size practical for its purpose.

I simply scaled it and sent it off ... got a 'manifold error'. So I tried again with increasing the export polygons ... still failed. The whole process seems pretty hit and miss.

I did have some trouble with booleans when I tried to run the cross supports all the way across and then build the pipe like cylinder and do a boolean difference to create an open channel. Finally had to use trim and then rebuild the cylinder back into a solid again.

here are the files ... maybe you can figure out why it fails.

thanks
eric

ps ... never mind ... I found a little closed curve that was still lurking there ... when removed the stl file went through just fine ... as an aside, it is still to expensive to be worth while for a small lampshade though it came down from $1600 to $340 just by making it 24% smaller overall.

Hi Eric,

To reduce the cost of RP, I would suggest:

Hi Ralf-S ... thanks for the suggestion.

I'm not sure how this would reduce the cost ... I thought I understood that the cost applies to weight and material type, primarily.

I guess it also applies to the size of the printer required to do the job.

Am I missing something?



cheers,
eric

Hi Eric,

Our RP service is calculated according to the used "space/box" and the material...
We have the information on the different "Space/box sizes" and
we can optimize our RP parts.
As application, we use (among others):
http://www.solidview.com/Products/SolidViewLite

Hi eric, yeah I see you actually had 2 little extra surfaces in there that were separate objects from the lampshade but overlapping with it, and getting written to the same STL file.

- Michael