That's a good idea jp, thanks. I'll just find one that ships to Ireland or an alternative in stock.In case its useful to others, I have found this set of imperial thread chasers invaluable for cleaning up corroded or otherwise damaged nuts and bolts.
https://www.amazon.com.au/gp/product/B00DTEFSWY/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
I have in the past used taps and dies, but they are not really recommended as chasers.
Looks like a .45 cal that hit a wall. I will certainly consider that Steve, thanks.Yuck, it almost looks like it was made of lead. On the note of the threads, might be easiest to just replace the stud itself. Knock the old one out and press a new on in.
MIchael, I'm not sure I've got pm permissions. Mod?
What's the ID? I'd be inclined to find copper pipe of an appropriate size and get a plumber to put a bend in it with a pipe bending tool. The securing tabs could then be soldered to the underside and everything painted?
Feels like it'd always be a weak point otherwise. I have to admit I never knew it was rolled from flat!