H. Notes for Designers

Dims

0.4mm (~0.016") is the min wall thickness. Design 1x, 2x, 4x of this value.

Objects will be oversized between 0.008" and 0.020"

Unsupported overhangs well have lower and lower quality they reach beyond 45 degrees.

Bridges upto ~0.6" can work. Longer bridges will have some droop that can be managed with CAM settings.

Threading

Small fine pitch threading in not a good idea, There are 3 method that work.

1) Use a hole that will get ~50% thread engagement and tap it. Make sure there is enough skin/shell to remove.

2) Use a hole that is dim'd to roll tap size, heat up a bolt and thread it in.

3) heat up a thread insert and thread it in..

Structure

fillet... fillet... fillet... 

when slicing orient the part knowing that the layer to layer bond is the weakest part of the object.

Post Work

Put a fillet or chamfer on the surface that meets the build plate. This will make it easy to remove

Build supports into the model to save time and better control defects in the same way as "injection marks"

anneal PLA at 80C for 30 mins for max strength. 

Special Issues....

making stupid things that will blow up in your face:

https://www.atf.gov/resource-center/docs/111313-hq-3-d-printing-technology-firearmspdf/download