Multiple test results from my first print, including some flexibility testing

Projects & Prints
21

TJ,

Excellent review, thank you so much.  Some Q’s:  What were the diameters of the horizontal and arched rods in test “P”?  Do you have any intuition as to what feature size might make meshes like “H” and “I” succeed?  Also,those long oblique support rods are intriguing; how thin were they, and how thin do you think you can go with those?

Regards,

-AH3000mk1

22

crazy test. I don’t think that the Form 1 was built to print a diorama in one single piece. Neither a $400.000,00 Stratasys printer can’t print it without issues.

23

Carl Allsup (AH3000mk1): For Test P, the diameters of the rods were designed at 1mm, but the diameter of the printed part varied between 0.6-0.9mm. The fine meshes were originally 0.3mm thick (the one from the failed v1.0), but I’ve managed to get them to print at 0.6mm thick using the 0.1mm layer height. I suspect that the pulling force of the mesh sticking to the silicone on the resin tank is just too great for 0.3mm, but so far 0.6mm has printed fairly reliably. Interestingly, the printed mesh doesn’t really seem to reflect the new thickness; it just looks like a correctly-printed mesh. :slight_smile:

The custom supports are about 1mm in diameter in most cases, with tips that taper to 0.3mm. I designed them to be 0.3mm at both ends to be easy to remove from the printed parts, but I’ve found that the supports tend to tear away from their base more readily during printing at that size. Instead, I’ve been trying to make sure the base is at least 1mm. They’re more stable at that size, and though they don’t break off as cleanly as I had liked. For the end that touches the part to be removed cleanly, 0.3mm or more works, but it depends on how firmly the support needs to hold the part. Parts that will have large, solid areas cured during printing (like a solid cube, for example) will hold more strongly to the resin tank during the peel process, so the supports need to be stronger. Parts on the print failed mainly because the bases of the supports were too weak, the touch points were too small, or there just weren’t enough to hold the part during the peel process.

Here are some general rules I’ve been going by from what I’ve learned so far:

  • The closer the angle of a surface is to completely horizontal, the more supports it will need to print correctly.

  • More supports will be necessary for parts that have large, solid-filled areas; less may be required for objects with thinner walls.

  • The strength of the total amount of supports for any structure must be greater than the strength of the pulling force of the peel process.

  • Supports are required at the absolute lowest points of free-standing or hanging-type objects. Without at least one support at those points, the print will fail.

  • Supports may be necessary for completely horizontal bridges, but the bridges can be supported from the sides as opposed to directly underneath (like Test P) as long as the touch points of the supports are at least as low as the bottom of the bridge.

  • Try to position supports along areas that will either not interfere with the print’s operation or appearance, or in areas that can be easily fixed after removal.

I’m in the process of experimenting with various support styles; this will be something I’ll do another write-up in the future, when I have more conclusive results. :slight_smile: