FDM printers can be extremely limiting. Due to the fact they need scaffolding/support to print anything with overhanging features. SLS prototypes allow for complete freedom in part shape.

I find I design within the constraints of the printer which is not ideal when the final component production method might be an injection moulding.

But having a 3d printer on the desk next to you _is_ invaluable and can help solve issues in a matter of hours rather than days or weeks.

Interesting — I found that given the amount of stuff that I actually needed printed, I am still below the cost of a decent-quality 3D printer. Also, I would not be able to print what I needed with a desktop FDM anyway, and I figured I will save time by not having to fiddle with 3D printers myself (usually the cheaper the printer, the more fiddling is required).

So, that's interesting that you found otherwise! Please definitely write more about that.

Yea, so I think scale, both in volume and in number, is a huge variable.

Our cases are relatively small so they can be printed in a couple hours. And during the development phase, we are going through hundreds of prototypes. (The fit has to be just right, so if a part is 5% off, we scrap it and reprint.)

Also, I love that you mention the fiddling as an annoyance. My co-founder loves fiddling w/ 3D printers so outsourcing all of our printing would take away that hobby :).

Another perspective here. At work we use a mixture of desktop (Form 1) and SLA printing (outsourcced). They have pros and cons. The resin printer is probably better resolution, but the SLA printers can do things like support-free printing which is really really useful for clean designs.

One problem with using printing companies is that they charge by volume, whereas most makers are concerned with the amount of filament they use up. This is cool if you can pack your volume with lots of designs, but it means that even a slight height increment on a big model adds a lot of the price. Then you have order minimums: 3DPrintUK, for instance, has a starting order of £40 which adds up fast.

Time isn't immediately obvious. We can rush an order online to around 3-4 days regardless of size. For small parts it's a no-brainer doing it in the lab, but for big prints there are print reliability issues, it still takes ages at high resolution and requires a ton of cleanup. And yes, fiddling is a pain, I don't mind doing it, but it can take hours to get repeatable prints.

Edit: meant to say we outsource SLS (selective laser sintering) rather than SLA (stereolithography - i.e. the Form) :)

Are you designing things or just printing other people's designs. For me that's the major difference. I almost never print others designs except when testing the machine.

And when I'm done with the iteration I'm likely to machine it.