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OK folks, here are the results of this morning's experiments. First, I tried the suggested method of using that saw, as Beth and Todd said. It worked better, and I think with some practice I might actually get some use out of it outside the miter box. But it is such a different animal than my other small saws, the ones with small kerfs and tiny teeth. I have one I use for a starter on my dulcimers, .010" kerf I believe, it is so smooth I can cut a straight line by eye. Oh well, another tool, another chance to start over from scratch on how to use it.

Anyway, I tried a couple of things on scrap blocks. First I took a piece of mahogany, used a backer block to support the Japanese Fret Saw, and carefully cut a slot. I then took a straight piece of fret wire (one of the ones I hammered straight yesterday before removing it from the board) and tried to hammer it in. For this first quick and dirty, I did nothing else. I did not file chamfers on the top edges of the slot, did not chase it with another saw blade just to make sure of width, nothing. Just cut it to depth with the JFS, and installed the fret. Much to my surprise, it went in like a dream. Just a few light taps with the hammer, and it was fully seated across its full length. OK, so far so good.

Next I took one of my previous failed zircote fret boards, and did the same thing. I carefully cut the slot, but it did not go quite as well. Did get it to work, but it was more work, and the saw jumped a couple of times, making one end of the slot a widened looking mess. (That's what always happens with this saw, maybe the new techniques and some practice will correct that in the future.) But I did get the slot cut, then carefully chamfered the edges with files, and installed the same fret as I used in the mahogany test. And guess what? Light taps did not work, no way no how. I was back to hitting this thing hard enough to drive nails, and I ain't talking finish nails either. I had to pretty much pound the heck out of it to get it seated.

So, now I have another piece of the puzzle, and a very good question for all you experienced folks. And it is this:

Does a harder, more brittle wood require a different treatment of the frets and slots than a softer or more pliable wood?

It seems so, from this experiment. If so, then what? A wider slot? Filing the tangs on the fret wire as a couple suggested? And once I get this figured out, do I need to remove all the frets I've already put in so I can rework them?

Thanks again,

_________________
Phil

http://www.oleninstruments.com

"Those who tilt at windmills are only considered insane by those who can't see the dragon."

In a word, yes. Softer woods are much more forgiving, so Ebony is much harder than Mahogany like for like.
Best thing to do is to measure the kerf (exactly) that the saw is giving you - use a feeler gauge or strip of wood in the slot. Then measure the fretwire with a digital caliper. That way we can start to eliminate the problem. It sounds as though the kerf and fretwire isn't matching up, for whatever reason. You certainly shouldn't have to drive them in like nails!

OK, here are the numbers:

Slot - .022/.023"

Wire: Tang - .020", Width across barbs - .036"

Measure the slot with feeler gauge, a .022" goes nicely, .024" won't go, .022+.0015 goes just maybe. For the wire, measured with a Brown and Sharp dial caliper.

I suppose for the sake of argument this means the barbs will have to displace/cut/sink into the sides of the slots around .007" per side. Is that about right? Too much interference for a brittle wood?

_________________
Phil

http://www.oleninstruments.com

"Those who tilt at windmills are only considered insane by those who can't see the dragon."

Don't know. That seems to measure up alright. I've just measured my fretwire and it's giving 0.039 across the barbs, wider than yours!
So now try one on an offcut but break the slot edge with a triangular file, smear a bit of Titebond/Pva on the fret (or use wax) and tap it home with good bench support. Use a stopped blow with the hammer, rather than letting it spring back as you would when hitting a nail.
Is the wire radiused?

For my experimental runs, the wire is not radiused, because my experiments are on flat scraps. It was for the actual fret board itself. But based on how hard the wire was to drive in, I think this is a valid comparison, though of course the radius might still have an effect.

OK, I tried your idea of using parafin as a lubricant. Cut a new slot, gave a generous chamfer to the edges, then drug the wire over the wax block enough to get a good coating. This time, it went in much easier. I used the plastic ended hammer in one of the photos in this post. This time, the amount of force needed to seat the fret was minimal - I could hold the head of the hammer about an inch or so above the fret, and let it drop, free fall. That was pretty much all that was required.

Now it is possible that I put a bigger chamfer this time, that might come into play. But when I pulled the fret back out, I didn't have as much tearing of the board as on the one I broke. So the wax may be the key.

I didn't use glue, for a couple of reasons. First of all, I use glue to, well, glue things in place. So for a fret wire that must be driven in place, does it need glue to stay in place? I thought not. (Another thought, another mistake maybe?) Second, I did a nice job with the surface of the wood on the fret board, exactly the finish i wanted. Buffed it out with steel wool before starting the fret work, felt smooth as silk, wonderful to the touch. After fretting, I will apply a coat of oil to protect it. I figured using glue would result in at least some squeeze out, meaning I will have introduced moisture on this smooth, dry surface. That will raise the grain next to the fret, and I'd never be able to polish that out as smooth as it was before. So if the glue is not needed to hold the fret in place, why risk that?

Getting closer to a solution I think. Right now I have the board in clamps gluing it back to the neck. I'll let it sit for a while, in the meantime, still open to any more insight into this.

_________________
Phil

http://www.oleninstruments.com

"Those who tilt at windmills are only considered insane by those who can't see the dragon."

You won't get much tear out when you pull the fret, that's partly what the chamfer is for - that and it helps to position the fret before hammering.
The glue helps to lubricate the fret. Don't know how much but it does seem to help. It also really does help in keeping the fret seated in it's place, once the glue is dry. Probably not needed but I doubt it will do any harm. Easy to remove if the fret is heated first.
You will get glue squeeze out. To prevent any 'glue clean up' raising the grain, wet or damp the fretboard before fretting. Rub down with fine paper after it has been allowed to dry, wet again and rub down. Just knock off the raised grain, don't go rubbing down into fresh wood. That will defeat the objective. After wetting and cutting back 2 or 3 times the glue clean up shouldn't have any effect. You can also finish with a coat or two of danish Oil and let it dry, then fret. I've used danish Oil on fretboards a few times and it really pops the grain or brings out the Black in Ebony. Unfortunately the effects are short lived i.e. when the instrument is played.

I`m really thinking that you should check out the radius overbend on your frets. If they`re bent too sharp, the barbs on the tang will push outward on the fretboard. One fret probably wouldn`t do it, but another 8-10 frets bent likewise and it'll add up, splitting the board.
I like to use the overbent method so the barbs will slide sideways and lock in, myself.
This is something to take note of.

_________________
Give me 50 cents worth of regular.
Check my oil too, if you don`t mind,,,

I had the exact same thing happen on my latest guitar except that the frets went in relatively easily. Everything went smoothly on the first 13 frets and then the 14th through 22 went poorly. My symptom was that they wouldn't stay in when I tapped them in. While I was trying to hammer them in, the fretboard split just like yours. Instead of lifting up from the neck, however, the ebony actually split.

The fix was to clamp the fretboard together and wick in thin super glue. I did the same thing for the split off of the neck.

After I fixed the cracks, I still had to set the frets. These frets were all in the cantilever portion so instead of hammering, I pressed them in with smooth faced pliers. The still wouldn't stay. I had to clamp a fret down on one side, wick in some CA glue, and after a few minutes, clamp the middle and then the other end. I had to scrape the squeeze out with a razor.

The reason that the frets would not stay in is that the fret board has no backing at that point and the fret slots expand and the cantilever started to bend down.

The problem you are having is due to the very hard wood that you are using. When you set the same frets into a softer wood, it went easily. The issues in not with the fret tang itself but the barbs. For softer woods, the barbs slide in between the grain lines. For the really hard wood, it puts up a lot of resistance. This will also cause a lot of back bow that may be difficult to straighten out.
You need to file off the barbs on the fret tang and then glue the frets in. I scrape the squeeze out with a razor and then rub vigorously over the frets and fretboard with 0000 steel wool. Clean up with with a rare earth magnet.

Thanks Mike, seems I am not the first to have this issue, and that's a good sign. That's why I come here! If you look at my original post, you will see that my board also split, right down the middle. I have since fixed that, glued the split and the board back to the neck. Next comes fixing the divots and the marker dot, then on to the frets.

What you are describing sounds like it fits what I am experiencing exactly. I did manage to get one in, No. 15 I think, by pounding the heck out of it. No. 14 was another matter. As you said, it did not want to stay in. One side then the other would pop out, the fret board would flex as that part was unsupported in the middle being over the truss rod, and the fret itself ended up getting hammered straight.

I think I'll try your idea, and file the whoop out of them barbs before I put them in. Then use some glue to hold them, as I am also concerned about back bow on that end.

Thanks again,

_________________
Phil

http://www.oleninstruments.com

"Those who tilt at windmills are only considered insane by those who can't see the dragon."

i have been using the stew mac fret press and am really happy with it.

http://www.stewmac.com/shop/Fretting_su ... _Caul.html

perhaps this would be easier on a fret board that might be susceptible to splitting?

you'd still need to work out how you were supporting the neck but it seems like you are sorting that out.

good luck!

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http://www.wideskyguitars.com
https://www.instagram.com/wide_sky_guitars/

One of the easiest ways is to cut a slightly wider slot and glue them in. All you really need then is a wood caul and a G clamp. I guess it's a bit easier than filing the edges of the barbs but if you haven't got a saw suitable then filing might be your only option.