Repairing a stripped thread

[zelk]

I am reassembling my drill and notice that one of the threads in the plastic body has been stripped. Apart from using a thicker screw is there a way of repairing this?
Zelk

[Bob38S]

Have managed the odd repair for this type of problem before using 2 part epoxy [the old Araldite] - the 24h cure not the 5minute stuff. Fill the hole, let it set overnight, drill the appropriate hole and screw in the screw. [clean the hole out with acetone first before gluing - removes some of the glaze and cleans the surface - be quick and don't use too much as it will soften some plastics]

If necessary, depending where it is, and you have the room, "overfill the underside and topside" to create a "lump" to give the screw more purchase and to "clench" the plastic should there be strain on the screw. Not pretty but it works if the hole you are filling is the sort where the screw clenches the case around the edge of the drill.

Hope this helps, regards,
Bob

[zelk]

Have managed the odd repair for this type of problem before using 2 part epoxy [the old Araldite] - the 24h cure not the 5minute stuff. Fill the hole, let it set overnight, drill the appropriate hole and screw in the screw. [clean the hole out with acetone first before gluing - removes some of the glaze and cleans the surface - be quick and don't use too much as it will soften some plastics]

If necessary, depending where it is, and you have the room, "overfill the underside and topside" to create a "lump" to give the screw more purchase and to "clench" the plastic should there be strain on the screw. Not pretty but it works if the hole you are filling is the sort where the screw clenches the case around the edge of the drill.

Hope this helps, regards,
Bob

Thanks Bob

I did think about using epoxy, I am glad you reminded me to use the 24h cure one.

I was thinking, rather than flood the hole, if possible, I would just line the inside with epoxy so that I don't need to redrill the hole. The screw should create a new thread.

As you pointed out, acetone can have an effect on acetate type plastics, I will try cleaning the outside casing to see what effect it has. If the plastic is susceptible to the effects of acetone, this will be a good sign as to how well the epoxy adheres.

regards,
Zelk

[Bob38S]

You're welcome - I forgot to mention that PVC pipe cleaner [MEK] is also good for cleaning up some plastics - as a degreaser and prep before you glue.

Your idea of just filling the hole to form the base for a new thread is a good one - if it doesn't work then you could always go further.

Regards,
Bob