Need Help Measuring Internal Thread

[richard.nott]

Have some how lost the oil drain plug out of my chainsaw (which perchance isn't made anymore) so I'm going to have to make one. I tried a pipe plug in it and it seemed to fit the threads but mine will have to be straight threads rather than tapered and accommodate an o-ring. Can a spring caliper and micrometer be used to make the measurement along with a thread gage.
thanks for the help
Richard

 

[Toolguy]

I would find the pitch with a thread gage and measure the minor diameter with calipers. Then look on a threading chart and find a size with that size tap drill and thread pitch. It should be a standard inch or metric size.

 

[goldstar31]

A bit of an ice cream stick( after eating the ice cream)
and a bit of modelling clay. Why make things difficult?


If you really wanted to do it properly, you would use a bit of bodge, gel it and get it out before the exotherm got fully underway.

A dentist- my wife or one of the kids would use an alginate. My father would have used a toy balloon and a bit of clay.

A bit of paper and a dirty greasy finger- depends on the hole.