Originally posted by u/Ok-Blood8662 at 2025-06-30T21:50:55Z
Was hoping I got good enough layer adhesion here, and I may have, but cracks formed at the pin holes.
Fortunately did not have this happen while firing. I noticed the cracks when inspecting the gun at my desk, flexed it, and it completely snapped.
Figured I would share as an example to others. Filament choice is super important in 3D2A. Be careful.
Source: https://i.redd.it/cm8nb5w9y4af1.jpeg
Source: https://b.thumbs.redditmedia.com/Hvop_ukpbveaGUcW1rK6eqQQ2dwiHHpLgQBXvciEnEw.jpg
u/K1RBY87 · 2025-06-30 22:01:17 UTC · score 70
Not that it likely makes a huge difference. But did you ream the holes before driving the pins or did you just send it?
u/Ok-Blood8662 · 2025-06-30 22:07:33 UTC · score 21
Yes, always drill my holes.
u/-250smacks · 2025-06-30 22:05:54 UTC · score 13
That’s what I was going to ask
u/No-Psychology3577 · 2025-06-30 22:07:52 UTC · score 10
Do you have too, even if you can insert the pins without any trouble ? I would completely understand reaming, if the holes gave the maker any trouble
u/K1RBY87 · 2025-06-30 22:57:49 UTC · score 23
It is generally good practice. holes that are 3D printed rarely are circular, or the correct dimensions. If you force a pin through it will displace the material, but it puts stress along the layer lines which can be the start to a crack.