Prototype complete. Now what ?

What kind of qtys are you looking at making? That will determine where you want to go to get your parts made and how much they cost.

 

so, you're definitely not at a point of going to china for molds

I think you'd be in good shape with 645 Taulman Nylon or send it to shapeways or something for laser sintered nylon.

There are *a ton* of options when you start looking at SLA or SLS processes, but you're going to need to find a professional / industrial service bureau that offers all of those options and you are definitely going to pay for it.

 

Both 645 and 618 are different types of nylons.

They are both extremely strong and heat resistant. If you get your print settings right, they're even pretty strong in the z-direction. 645 is stronger and more heat resistant, but also more expensive. 618 has come down in price enough to be about the same price as premium ABS or PLA, but 645 is still pricey. Although if you start comparing it against other 3D printing methods to get your part prototyped, it is comparatively cheap (i.e. 1 lb of laser sintered nylon is going to be way more than 1 lb of 645).

The downsides to these materials is that they are stringy, soak up moisture, and have a pretty significant tendency to warp, so you have a learning curve with them that is steeper than most other materials. Taulman has a ton of into on their site to help learn.

 

You'll probably need a replacement hotend (like an E3D) for some of that stuff (the print temps are perhaps >230 in some cases).

However, the tests I have done with Nylon are positive...it is a sturdy print material for sure. Like Matt says it tends to warp (more so than ABS in some instances) so other things may need to be tweaked (add strategic 'mouse ears' for starters).

 

I did a print at 250C in 618 last night and it is incredibly strong. So, you might want to just start out with that since it's cheaper.

 

See this object:

http://www.thingiverse.com/thing:66030

Notice the round sections at the corners? Those are what I mean. They add grip and help avoid warp. You can easily trim this off when the model is complete. tesseract had provided STL versions of different sized ones (I reattached one here) just place them on the object bed in Repeteir and when sliced it becomes a solid object (with these added to the first layer). The STL here is very thin (one or two layers if memory serves) very easy to remove.

 

More fill = more warp. Warping occurs due to coefficient of thermal expansion; the material shrinks when it cools which puts a lot of stress on the base. The more material in the model, the higher the forces exerted when it shrinks.
Slower speed will help to some extent especially at the first layers just because you're disturbing that bond to the base less.

Nylons stick well to cellulose fibers. The recommended best build surface is Garolite LE roughened to expose more cloth fibers (available from mcmaster carr). Depending on how big your part is, you can also print it on blue tape, wood, or a sheet of nylon. There is advice at taulman-3d.com.