Neat effects, Oli!

Prime Gray (yes it's SLA) and Form 1 prints should be very similar. Prime gray also has those little bumps from the support structures.

In your case, I'd look up someone with good reviews on 3DHubs or MakeXYZ with a Formlabs printer and have them make some parts for you to see if they're good enough for what you need, and go from there. Might turn out to be your best option!

xiombarg, the one experience I had with a Form 1 was not that great. Now I'm not saying this will always be the case, but remember it its the marketer's job to show everything in the best possible light.

Anyway, I ordered some parts to be made on a Form 1 from a guy on MakeXYZ. These were mechanical parts, and they had to fit together precisely. It turned out he had a problem with his machine, so small parts worked ok, but the big prints kept failing. He had to get the larger parts made on an SLS machine for me, and get a new printer from Formlabs support.

When I got the Form 1 parts, they had not been cleaned very well and were still sticky with resin. They also needed some sanding, because where the automatically generated supports touched the model, there were a bunch of little bumps that kept the parts from fitting together neatly. Overall, the parts looked good but were not as dimensionally accurate as SLS.

BTW, Shapeways and Formlabs have a contest right now...maybe you could get one for free! Free would be worth it

If you're thinking of ordering your own printer, I'd find a way to get some samples or a few of your parts made using a printer like that, so you can see if the quality is good enough. You may find a makerspace near you or use the Where to get your Models 3D Printed thread to find a printer. Another alternative is to request a sample from the printer manufacturer.

i.materialise plugin is available here, but it just uploads the model to their site. To get the price you still have to upload it.

Oli, I agree a plugin to get the pricing right inside of Sketchup would be awesome. I know both Shapeways and i.materialise have API's that allow developers to access that info. Gonna have to learn Ruby or talk to one of our plugin gurus!

@xiombarg said:

The only other explanations I can think of is if they automatically up-charge with a higher polygon or edge count, perhaps assuming that the more complex a model is, the more possibility that it will require more time and/or labor to load it, clean it, etc.

It could also be that certain shapes require a certain printer over another, which they have a different price structure for their machines?

Pricing at Shapeways or i.materialise is not affected by model complexity or polygon count. They typically have a set handling fee per model, then charge by volume as shown below. Each material has a different price that reflects the cost of labor and material involved. As I said in my previous post, ceramics at i.materialise is the only material that is priced differently.

Just now saw your edit from 3 days ago Oli...yes, i.materialise calculates price for ceramics based on surface area.

@unknownuser said:

Pricing for ceramics, which is $0.18/cm², is based on the surface area of your model, not on the volume of material used.

AFIK, that is the only material priced according to surface area. Shapeways charges ceramics by volume now, although they used to charge by surface area as well.

The prosthetic projects are so awesome! Costs are ~1% of a typical solution, and they're helping people on the ground right now with the little desktop printers.

Oli, I used a simple test to figure out the bounding box thing...upload a model of 2 cubes and check the price on that. Using the same model, move the cubes apart so the bounding box is bigger but the volume remains the same, and the cost increases.

Good question! Larger bounding box, most likely. A model that takes up more space in the printer means less room for other models to be packed in around it.

In other cases, like Shapeways strong and flexible plastic, they give you a discount if the model fills 10% or greater of the bounding box.

Edit: This is almost always the case when using a print service where the entire build area of the printer is filled up with models, and printing supports is not a problem. For a home printer, less material almost always means a cheaper print.

China...no kidding

@olishea said:

Yeah glass idea is great! Can it be injection moulded any way? Or just cast?

Glass can be molded, that's how glass bottles are made. I don't know much beyond what I've seen in "How it's made" Youtube videos though.

One thing I really want to look into is glass. How sweet would some funky CAD generated designs look like in glass??

I know they can 3D print a model, then make a mold around that and cast glass, but once again for larger models the 3D printing becomes cost prohibitive.

Must...find...cheap, large scale 3D printer...

I don't think you're going to find any other decent rubber material that can be 3D printed.

What you might look into for that quantity is short-run injection molding, where you can make the parts in plastic, hard rubber, or a few other materials. They'll have to make a mold, which is pretty pricey, but then the cost-per-part is waaaay cheaper than 3D printing or milling.

@olishea said:

Getting some better voronoi objects, would be cool printing these in the rubber-like material.

You can!
Shapeways: https://www.shapeways.com/materials/elasto-plastic?li=nav
i.materialise: http://i.materialise.com/materials/rubber-like

Check out the video to see how it flexes.

D'oh, I meant to type Meshlab, but meshmixer popped out Meshlab is the one I use for converting files - works great for that. I've used Meshmixer for building support structures for my desktop printer, and for light editing of STL files. It handles sculpting pretty well. I haven't used it to full potential (I like my Sketchup ), but has some very handy features beyond Skectchup's capability.

Re: optimizing for CNC, I would chat with the customer support at your CNC provider to see if there is any way that changing the geometry (without changing your design intent) would bring the cost down. This link briefly explains what I mean.

@olishea said:

That's great thanks. Just putting some quotes together. Got some CNC quotes from UK but it was £421 for only a small item, less than 100 centimetre cubed.

CNC milled Aluminium is £421 whereas 3D printed Alumide is £84.73 although not directly comparable materials. Brass is also slightly cheaper when printed. Although I don't the think quality of either will touch CNC finish.

The beauty with 3D printing is that it makes you think outside the box to remove material and save money. Well that's the plan lol

Oli, for the CNC'd parts, did you optimize the model for the process? ...or did you just get a quote for the same model that you used for 3D printing? I'm guessing the cost may be significantly less if you can save them repositioning time.

@olishea said:

Would you need an internal support structure to print the attached models?

Depends on how you're printing it. For any industrial process(like i.materialise or Shapeways uses), you don't need to think about supports. For printing on a small desktop machine, you would need additional supports.

I've only used meshmixer for converting files...pretty sweet what you're doing with it!

Yeah, I think you're right about cost. I see cost as a limiting factor even with professional plastic printing, and is one of the reasons 3D printing isn't used more frequently. When you do get a cheap print, say from a desktop printer, then the quality often isn't good enough to be taken seriously in a professional setting.

Haha, Thom!

I have the same problem as Dave, so I'm glad to hear you know what it is.

Chuck, that is some fantastic work

Were the models intended to be used as displays, or what was the end use?

I found a photo of your castle model on this blog post, listed under #4, ExOne 3D printers.

You picked a good one, Ken!

Here's a photo of a part, I think the one being made the video above:

There are more photos of the machine here: http://imgur.com/a/Knog5

Dukejazz, I have heard the value of the machine is over $1 million, and the raw titanium powder used in the machine is ~$500/kg.