repairing thread damage

[ash74]

Hello All

I am wondering if anyone has tips on how to repair thread damage in plastic? I was working on a model & it accidently fell out of hands, the most damage was to a part that was screwed on. I could use a longer screw, but I don't like my chances of finding one, that is less then 5mm longer. I have looked in my "bone yard" for one that suits to no avail. Does anyone have any suggestions? Thanks

Ash

[NOBLNG]

You could drill the post out and glue in a plug of styrene or sprue. Then re- drill for the screw? You could also make up some “sprue-glue” . Put some on the screw, install it and wait for it to dry. I don’t know if that would permanently glue the screw in? Maybe very lightly coat the screw with a grease or oil first?

[Ace-Garageguy]

1 minute ago, NOBLNG said:

You could drill the post out and glue in a plug of styrene or sprue. Then re- drill for the screw? 

Exactly.

[Mark]

Or, if a particular size of styrene tube is a good fit (not a loose fit) in the hole, you can glue it in and redrill to fit the screw.  If the tube is thin enough, redrilling may not be needed.  This is what I do on stripped or cracked body mounting posts.  I'll also add a short piece of larger tube around the outside of the post to make sure the crack doesn't separate again later.  

If the "inside" tubing doesn't fit exactly, get the next larger size and sand the outside until it does fit.  Sanding will thin the wall thickness too.  The "outside" tube should also be a tight fit; you can sand the outside of the post if needed.  Actually, you could use a sheet plastic "collar" (flat piece drilled to slip over the post, right at the crack area).

[ash74]

Hi All

Thank you for your suggestions, Have tried the plug method, still in progress. It seems to be working, again thanks

 

Ash