I've owned a Jaws II fret press for years, as well as the full Birkonium caul set, but I've never been able to get it working well enough to replace hammering.
I can press a fret 80% of the way to fully seated with no problem, but that last few thousands to get it really well seated just aren't happening, no matter what combo of cauls and how much pressure I'm using. The amount of futzing required also seems excessive, and I always have to finish off with a few hammer blows. At the moment it's taking more than twice as long as a hammer-only fret job, with no discernible advantage that I can see. Since there's so many very well-regarded luthiers who use it, I'm operating on the assumption that my struggles are down to user error, equipment malfunction, or both. So I'm asking for help - if someone with some Jaws II experience could help me figure out where I'm going wrong, I'd really appreciate it.
Prep process:
1. Prep board - I sand to achieve dead straight FB surface with an accurate, consistent radius (I most often use 16")
2. Prep slots - check slot depth is appropriate, saw deeper if needed, bevel top of slots with triangle file.
3. Test slots - I have a piece of fret wire with the barbs lightly filed off which I use to test each slot. I aim to get the slots in a state where a light tap on the barbless fretwire is enough to seat it fully.
While I'm not achieving great results, I've arrived at the following process, which gets me the closest and requires the least hammering to finish the job:
1. Lightly tap in both fret ends with a hammer to hold fret in place and upright.
2. Start pressing with a tighter radius caul (say, 14.75") to get the ends well seated. (Have to walk clamp back and forth and press from both sides)
3. Press middle of fret down with a slightly flatter caul than the board (say, 17.5") to seat the middle (Have to walk clamp back and forth and press from both sides)
4. In theory if all the above goes well, this is where I would clamp the fret down with a caul that matches the board (16") and wick CA under the fret for insurance. But it never does, so this is where I use a hammer to fully seat the fret.
I notice when applying pressure that my Jaws only really squeezes down tightly at the end of the fret closest to the clamp bar. So I have to squeeze a bit, back off the pressure, walk the caul along the fret slightly, squeeze again, remove the press, flip 180 and reapply it with the bar of the clamp on the other side of the fretboard to get *that* end down, back off the pressure, walk it along, squeeze more etc. Here's a pic kinda showing the issue:
After all that futzing, at best I get to the point where I can still slide a .009 feeler gauge between the fret crown and the fingerboard surface. At this point, I am applying as much pressure as I can with the clamp and the fret won't budge further, it just stops like that, part-way to seated, with a the .009 gap visible under the crown. If I remove Jaws and whack it with a hammer it sits down perfectly.
Where am I going wrong? Does my process sound OK? Could my Jaws II clamp itself be faulty? Maybe there's too much flex in the bar, or it's slipping, or something. Maybe I need to prep the slots differently?
) other than I used CA initially.