printing high precision prototype parts

[awerby]

How much precision do you need? Pro-grade FDM printers will hold about +/- .0035" per inch: http://3dprintwestern.com/3d-print-accuracy/ . I'd expect consumer-grade printers, which are more flimsy in their construction, to be somewhat less accurate, although manufacturers don't seem to be releasing much data about this that I could find. Maybe someone else here will have a link to measured tolerances for various low-end printers. A complicating factor is that accuracy varies depending on the type of feature you're measuring. Heights tend to be more accurate, for instance, than interior holes; as well as mechanical issues with the machine, there are also shrinkage and irregularities in the deposited material to consider.

At the upper end of the consumer spectrum, there are some FFF models that claim to be able to print with soluble support material, as has been standard in the Stratasys machines for some time. I haven't been able to confirm this for myself, but others here say that PVA support filament works with PLA, if you have a machine with dual extruders.

Andrew Werby
www.computersculpture.com

[bigHUN]

How much precision do you need? Pro-grade FDM printers.....
...there are some FFF models that claim...

Today morning got some sample prints, not really I was expecting. My impression currently that the SLA process is my way to go.
Investigating now the prices for both the machine and resin. Thanks all for feedback