T-nuts; heat treat or not?

[kwoodhands]

(09-18-2017, 04:22 AM)Pete O Wrote: I'm making some T-nuts out of a chunk of forklift tyne- presumed 4140- wondering whether I should heat-treat them when done or if I'm best leaving the material as-is to avoid making the threads brittle? They'll be threaded 1/2-13 UNC to match some existing hardware and set aside for use on the shaper.

I wouldn't bother to heat treat unless you will give them heavy use. I have made T-Nuts from CRS, even aluminum for light duty work holding. I use an aluminum T-Nut to hold a indicator on the mill. I threaded one end of a 3/8 shaft to fit the T-Nut. The indicator bracket slides over it and locks at any height. 
If you make T-Nuts, make sure  you deform the thread at the bottom , prevents the studs from chewing up the mill slot. Store bought T-Nuts are made that way. I do this with a hammer and cape chisel. 

mike