I'm trying to make a replacement part for an articulated magnifying lamp. Specifically the bottom joint that has the post to fit the clamp. Got it all measured and built and it fit. However after a short while, the tension pulled the spring hooks off and pushed the bottom bolt through the sides of its holes. I tried another print, this time at 100% infill, and shored up the spring hooks. This time it lasted several weeks, but it pushed the screws through the base plastic again. I'm thinking of modifying the design to add more material around it, and redesigning the holes (somehow they ended up as ovals in the print, likely due to a rogue resize I didn't notice). Does anybody have any tips for designing and printing something that will have a moderate amount of strain on it? I've attached some pictures so you can see what Im talking about. I print in PLA.
Where my joint failed.
21616803_10155509464640569_1956945899_o.jpg (190.66 KiB) Viewed 119 times
The kind of lamp I'm trying to fix
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What my design looks like
9-11-2017 5-07-01 PM.jpg (49.77 KiB) Viewed 119 times