3/4/14

Fret Level and Crown on the Kay K22

This thing is starting to look like a guitar.  I have a few more things left to do before we hear the first twang.

The next thing to do is to level and recrown the frets.

Quite a few 'second-level' American-made guitars dating from the 1930s to the 1950s, such as this Kay, used brass frets rather than nickel.  I can only surmise that the brass frets were less expensive.  To my knowledge, neither Martin or Gibson ever used them.  Personally, I like them.  They're easy to work with, they look good (although they tarnish quickly), and they sound good.  The downside is the wear, although ironically, the instruments I've seen with brass frets haven't shown bad wear.

Anyway, on with the show.

I forgot to show the hole through the neck block to access the new truss rod's nut.  There is a hole at the top of the block now to stick an adjustment tool though and turn the nut.

I also went back and forth on whether or not to make an access groove in the brace under the fingerboard extension.  In the end, I finally just did it.  I used the flex attachment for the Dremel and sanded a circular groove.  

I mention this because the first thing to do in the levelling process is to make the fretboard as flat as possible by adjusting the truss rod.

Here's a mirror shot through the soundhole showing me adjusting the truss rod.  It works!  The neck was pretty straight - it just took a small turn to make it level.

Also see the hack job access I made in the brace.  Hard to work on something you can't see too well.
At least I don't have to see it all the time.

Now we mark the fret tops with a marker.

What we'll be doing is sanding them with a level block, until all of the marks are gone, which means all the frets are at the same height.

The aforementioned levelling block.  It's Corian (I think) with some 320 grit paper on it.  I just use spray contact cement which holds it temporarily.

The corian is super level - within a zillionth of an inch or something.  Way more accuracy than we need, but there you have it.

Back and forth, side to side in a sort of circular motion.  You'll figure it out if you try it. 

Don't need much pressure, just use the weight of the block to follow the radius of the frets.  It's not rocket surgery.  If I can do it, anyone can.

In a couple minutes, all of the marks will be gone.

Here are the freshly levelled frets.  Green all gone.  Ready to be crowned.

The dust is brass - I just vacuumed it up.

I've written about this process a few times, and I always have a hard time photographing the frets.  I got lucky this time.

This is the 8th fret viewed from the bass side.  See how flat the top is?  This is extreme, since we've just levelled it, but very worn frets will become flat too.  This shows why frets need to be redressed periodically (until there's not enough material to work with).

A fretted string should only contact one point on the top of the fret for accurate intonation as well as no buzzes.  We're going to crown this puppy (and all of the other frets) to a nice arc.

These are relatively small frets - typical of the time period.  Some players hate 'em, but I like them.  I suppose it's because I have so many instruments with them that I'm used to them. 

The fret crowning file I'm using is also a narrow one to suit the fret size.  It has a coarse and a fine side.

This time I counted the number of strokes - about forty or so with the 'coarse' side of the file until the fret was crowned.  Then another 12 or so with the 'fine' until the flat shape was gone.

One fret end popped up in the process.  No big deal to fix it.  Just wick some thin CA into the slot, hold it down with a tool (I just used the end of the file), and all is well.

I didn't touch the fret ends at all, just the tops.  For one thing, they were dressed so they fall inside the binding, so they don't stick out over the ends of the board.  Second, they were very nicely dressed already.  No extra work required.


Here's how much material gets clogged up in the fret file.  I found that I needed to use the little brass removal brush after each fret was crowned- and more frequently in a couple instances.  If the material gets clogged in the file, it won't cut well - and it will just grind the material against the fret.
After the crowing, a polish with the magical, mystical Fret Erasers.

In the past, I've started with the 150 grit (which is what I have in the picture).  But this time it seemed like the 150 and the 400 were actually flattening the fret tops!  Maybe it's because these are brass frets and are softer than nickel.  At any rate, I just used the 800 and then 1000 grits to polish this time. 

This might be something to be aware of if you use these.  I really like them, but the lower grits could take off more material than you expect.   Possibly.  Jury's still out on that one.

Here we have that 8th fret after crowning and polishing.  You can clearly see the crown shape from this angle.  Quite a difference. 

Not only will this play in tune, it's super smooth on the fingers.

Here's the finished fretboard after I cleaned it and used Dunlop Deep Conditioner on it.

The board was filthy - as so many are.  But now it looks great.  I'm pretty sure this is Brazilian rosewood.  Probably worth more than three of these guitars are.

Now I need to make a new saddle and nut and set it up.






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