I used (and enjoyed using) holdfasts in a friend's shop, and now that I'm getting my own workshop set up, I'm in search of a pair. There is a local smith who can produce them, but I've got a couple of questions before I put in the order. I've not been able to ask my friend for a variety of reasons, including his failing health.
First, shank size. 1/2" or 5/8"? My bench is relatively new and does not yet have dog holes, so that will not play into. Any real difference, or does it just depend on what stock is on hand?
Second, bench compatibility. My relatively new bench is also relatively crummy. Solid, heavy, and flat, but the top is 3/4" ply covered with 3/4" MDF. When I can, I plan to construct a more traditional top, but so far it's been a suitable first bench. I'm wondering if a) the holdfast will even grab in that material and b) if so, will the MDF just blow out immediately? (Which might give me the excuse I need to get going on a better bench.)
Thanks for the help. I hope this hasn't been covered at length - I searched several threads but couldn't find satisfying info.