Question about tight fret slots

The slots need to be at least as wide as the tang of the fret. It is OK if the barbs stick out further. Just take a fret and see if it slips in the slot from the bottom of the fret between the barbs. If it is too tight, you may need different frets or a different saw.

If the fret tangs are too wide for the slots, it may create a nasty backbow in the neck with each fret pushing the fingerboard apart. It will also make installing the frets a nightmare.

 

What do the fret slots *measure*?

 

The slots should be the size of the tang between the barbs. Too tight a slot will cause the fretboard to bow backwards.....don't do it. A .023 saw is what most fretwire these days calls for. Buy a fretsaw and do it correctly.

Guitar Fret Slotting Mitre Box (luthiersupplies.com.au)

Fret saw, Beech handle (lmii.com)

Fret Saw | stewmac.com

 

Take a piece of your fret wire and file the barbs off of it. I like to bend it into an L shape like shown. Use it to test the slots - if the little gauge fits and goes down to the crown then your fret will too. If it won't, widen (or deepen) the slot



ps - if you change fretwire make a new one out of the new stuff. The tangs vary even within the same manufacturer

 

when you get the slot width sorted ... I use a triangular file to widden the very top of the slot itself 2-3 trokes is usually enough... so the barbs still are able to hold, practice on some scrap wood to get an idea , not doing this can introduce back bow to your neck. Don't ask me how I know this.

 

Recently I replaced my fretsaw with one from hartville hardware via eBay (no affiliation).

$30 shipped brand new, as far as I can tell it’s the same as what stewmac sells.

 

Good luck and enjoy the journey!

 

I don't believe this is the case. It's the barbs doing the back bowing and they are still being jammed in there. The chamfer is to avoid chipping on fret removal, easier installation by allowing the fret to start a little more easily, and more significantly, to allow the fret's fillet to seat. The fillet is the curved shape where the tang meets the bead. The fillet is produced by the extrusion process in making the fretwire. I talk about this in most of my neck build threads.


If the fret slot is smaller than the fret without the barbs, then it is a case of an interference fit which expands the slot to accommodate the fret.


See this thread post 361

Let's make a neck! | Page 19 | Telecaster Guitar Forum (tdpri.com)

 

If you're not certain about the width of the slot a saw cuts... simply make a cut or two in a scrap piece of hard wood then take feeler gauges and check... now ya know...

 

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You can also adjust the kerf of your saw cut width to be exactly what you want, instead of buying a new saw.

I use a $10 mini pull saw from Harbor Freight that has too much kerf so I hammered the kerf narrower to get the right size fret slots. Then I used double-sided tape to hold a depth stop strip of wood to the side, which also stiffens the saw blade for straighter cuts.

Here is how Paul Sellers sets saw teeth.



Running a triangle file along the top of a fret slot to break the edges and put a slight lead-in bevel makes installing frets easier and if the frets need to be replaced after many years of playing you'll have less chip-out so the repair guy will give you a thumbs up from the future.

Other advice: only install stainless steel frets.

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One more little recommendation. I always glue frets in - just a couple of dots of medium CA or a swipe of HHG before I press it in. I think it is very important with bound fretboards and it seems to lubricate the slot, I used to wick the CA in the ends of the slots but since I do mostly bound boards now I just put a two tiny dots near the binding. I figure that anyone refretting one of my boards better be using heat when the pull the frets.

And make sure the slots are really really clean. If you've been sanding on the f/b there will be dust in the slots - get it all out. An Xacto knife works pretty well for cleaning the slot, then check it with the little L that I showed before.

 

I can't for the life of me, imagining somebody trying to set the teeth on a fret saw. I'd need an electron microscope.