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So, I’m celebrating this Labor Day by working on fingerboards for the uke “kits” I am building for a “no experience needed” uke building class I will lead in a few weeks. As I was hammering in a whole lot of frets (over 200), I noticed something about my fretting hammer. For getting the fret mostly seated, but not completely driven home, yet evenly seated, the nylon face worked best. For driving the fret home, and fixing any specific gaps, the brass face worked best. At some point in the process, I developed the opinion that the nylon face spreads the force more evenly over a longer section of the fret, but the brass face concentrates its force on a much smaller section of the fret. This is why a blow from the brass face can leave the fret fully driven at one spot, but still sticking out one the other end, and a bit wonky because of it. But if I use the nylon first, get the fret mostly there, then flip to the brass for finishing up, I can get it pretty darn perfectly seated everywhere.

I don’t intend this to be a “hammering vs. pressing” debate. Pressing wasn’t in the cards for this project, so we can save that for some other discussion. This is about noticing how one of the faces just works differently from the other, independent of the concern about potentially marring the fret. Has anyone else noticed this about the different heads for fretting hammers?

In any event, I celebrate Labor this day, and hope that everyone has had a relaxing celebration of their own, or soon will.

I have two gunsmithing hammers with nylon and brass faces I use for fretting. When for whatever reason I don’t press them in, I use the hammers just the way you describe and agree, the faces make a difference.

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Steve Smith
"Music is what feelings sound like"

Being softer than brass the nylon face compresses more, and stays in contact with the fret for longer. This is probably one reason it spreads force over the length of the fret more evenly. The nylon face also spreads the work out over time, and most likely reduces the maximum force level, so it can't overcome high levels of friction as well.

The longer contact time changes the sound of the blow too. As long as the hammer and 'anvil' are in contact they can't vibrate freely, so the longer contact time of the nylon tends to damp out high frequencies. You can hear this if you tap on the saddle. The brass face gives a sharper sound because the shorter contact time drives the higher resonances better.

Excellent observation, I will give that a whirl soon!
I was typing "Is there such a thing as a small dead blow fretting hammer?" but searched SM first and discovered there is, and I have one. I have two fretting hammers, one with the two sides, and the dead blow, both from SM (the two-sided one came from an Ebay tool lot, with a bunch of fret wire). I embrace testing different methods of work so I'll cut some slots and use all three (nylon, brass and deadblow). Thanks for sharing that, my installed-not-leveled fret height is not as uniform as I feel it could be.

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Measure Twice,

Karl Borum

Exactly and this is physics coming into play. The softer the face the more the compression of the face (and even the fret to some extent) extending contact duration. With more duration the "blow" becomes more of a "push."

Karl—

I was using the StewMac deadblow for this project, although I own the other kind, too. The deadblow has the softer, plastic side and the brass side. With this opportunity for extended observation (lots of frets to install all at once), I developed a routine of starting with the plastic side and finishing up with the brass side. With the assistance of magnifying eyewear, I was able to make sure the frets seat just right, using the brass side for spot tapping after the plastic side got the fret mostly there, but not all the way there, all along the fret. In the past, I just used whichever face seemed to get the job done, without really thinking about how one of them is better at one thing, while the other is better at the other thing. I assumed the plastic was for situations where you don’t want to risk marring the fret. Now I have a better idea how and when to use each on the same fret, every time. When not pressing, of course.

Then this is a method of work you've developed and not just an observation. Thank you for elaborating Don. I ordered some $4 on-sale, shortie granadillo fingerboard blanks@ SM' last night- I'm going to radius and slot them and do some fret hammering practice using your method- I have a boatload of fret wire I won't use otherwise and need to develop some degree of consistency. I'll also get to use both hammers

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Measure Twice,

Karl Borum

Karl--

True, but I wouldn't have developed the method of work without making the observation. Figuring out that the plastic affects more of the fret than the brass led me to start with the plastic, get the fret mostly driven home, then use the brass to take it the rest of the way, focusing the brass exactly where along the fret it needs help to seat perfectly. That wound up consistently being the way to get these frets to behave right.

On the last couple of fret jobs I discovered a technique that allowed me to fully seat small problem areas that weren’t quite seated. I used the plastic side of the hammer and slowly "ironed" these areas using considerable pressure by holding the head of the hammer. My theory of why it worked was that the "ironing" avoided the rebound of hammering.

We press all our frets with the StewMac Jaws II and the custom set of cauls made by Andy Birko. Always works great and in time you learn some very creative ways to press frets regardless of where they are located.

The only time in the last ten years I've used my fretting hammer and I do this often too is to use it with a wood block to knock my nuts off.

When we press a fret we can use the press if we need to say for a pesky fret end that wants to be spongy to clamp the fret down as the glue dries. Can't do that with a hammer, well you could but you have to stand there and be a human clamp with a hammer...

This is very relevant -

https://www.instagram.com/reel/C_foLf2u ... M0NHI1aGJ6

Sent from my iPhone using Tapatalk Pro

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Love it! I'll have to try it.

Yeah, how cool is that!

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It's not what you don't know that hurts you, it's what you do know that's wrong.

Early on in the work at Greenridge, I was having issues fully seating frets with a hammer, either resorting to a press or heavy clamping to get a consistent result. Granted, there are fret materials like wider/higher stainless that are happier being pressed, but for routine work in nickel silver and anything under 45 x100 in stainless, hammered installation was efficient and gave us a well-seated fret. Eventually, I determined that most of my fret-seating issues were preparation-related rather than hammer selection or technique. As has been mentioned before on the site, some wires just need a wider or deeper slot, or more slot-edge radius to properly seat. Wet-setting into hot hide for nickel silver helps a bit with seating by softening the fret slot edges, but eliminating the fret slot geometry issues and properly cleaning up the underside of the crown after trimming the tang back on bound fretboards addresses root causes.

The best small dead-blow hammer we found for seating frets was the Stanley 5 ounce Compo-Cast Dead-Blow Hammer #57-540 (Zoro has it for $20 before the usual 15% off and free shipping if you sign up to be electronically nagged). The overseas-made StewMac item is not nearly as versatile, having just one soft face, versus the two on the Stanley of slightly different radii. Even after regrinding the brass face on the StewMac, all three luthiers in the shop opted for the Stanley and the older wood-handled,hard-plastic/flat brass faced 'fretting hammer' offered by LMII, StewMac, and other suppliers. Having a slighly-radiused face on one of the available brass hammers in the shop was handy for getting a bit of a re-radius on the fly with over-radiused stainless, but a flat face largely avoids that re-radiusing effect when seating into a particularly hard or stubborn (usually inadequately-prepared) fretboard).

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For the times they are a changin'

- Bob Dylan