On 27 Oct, 22:24, Rod wrote:

Car body filler ain't going to be a flier. Regardless of how good it
might be, I don't have the right feelings about it for this purpose. If
I had to do anything more substantial myself, I would prefer to make my
own metal plates.

I can't imagine the (sensible) application which would pull an M10
nutsert out of softwood, but if you wanted to do your own plate it
doesn't need to be complicated, take a mending plate or similar, drill
an 11mm hole in it, thread the rod through, whack a nut and big washer
on the back, counterbore the timber and screw the plate on the face
of the timber. In fact, you could do that with a nutsert and the
right washers for belt and braces.