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Solving and Avoiding Stripped Screw Threads In Plastics
Allen J writes:
“Does anyone know how to fix stripped screw threads in plastics? I have been disassembling then re-assembling things and some screws are not gripping the plastic. I thought I was being careful re-inserting the screws into existing holes, but obviously not. I can’t be the only one with this problem?”
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Squirt a small amount of ‘Vallejo’ plastic putty into the hole before carefully inserting the screw (do not overtighten). When it dries it should hold the screw tight.
A drop of thick CA (super glue) works well if it’s not too worn.
“Apoxie” Clay.
Drill out the hole to the size of any styrene rod that you have on hand and glue a piece in the hole. Allow it to set up then drill the appropriate hole for your screws to cut a new thread. Do not over tighten the screws.
fill the stripped hole with epoxy and then grease the threads on the screw and insert the screw fully while the epoxy is still soft. do not try to tighten the screw at this time. Once the epoxy sets up you will have good threads and the grease will allow you to remove the screw.
All of these answers will work greatly, remember, this is not full size equipment to work on, treat it gently and with respect and you will get many years of enjoyment from your Equipment. I learned the hardware my self.
All of these suggestions are excellent. Can’t wait to try the epoxy & oil. I have, many times, cut a sliver of plastic and just dropped it into the hole. Make it a little shorter than the depth of the hole. It is very quick and reliable. I keep all our used gift cards and cut very thin slices using scissors. Thin enough that it will spiral when being cut. The plastic, when cut very thin, is soft and won’t blow out the hole. If you are having a hard time turning the screw, the piece is probably too thick. As George mentioned, apply pressure very gingerly. Glenn
I break off the tip of a toothpick and stick it into the hole with point up and tighten the screw back in.
The biggest mistake is to force the screw to create new threads. Anytime reinserting a screw, very carefully turn it counterclockwise with not much pressure. You can feel a slight change as it drops into the existing threads and the insert force will be much less and will not enlarge the hole. I realize this is not your answer but it will keep this from happening again.
One more trick: put a drop of liquid poly in the hole. This will melt the inner surface.
Faintly polish the screw with oil so it doesn’t stick. Put the screw in and give it time to set.