Fret hammering technique

[Gitarren]

So I did my first fretwork ever, and for parts of it I used a hammer with a plastic end. 

A recommendation seems to be hammering the frets in with one firm blow, like described here:

Quote

Think of the hammer's impact as one single dead blow to the fret, with no recoil. The hammer head should make solid contact with the fret, seating it with only one blow.

https://www.stewmac.com/How-To/Online_Resources/Learn_About_Guitar_and_Instrument_Fretting_and_Fretw/How_to_hammer_frets.html

It seems very reasonable that bounce should be eliminated, which is also described in the article. But for the rest, is it really such a good idea to use one firm blow when using a hammer for fret insertions? As the hammer is not covering the whole fret, isn't there a risk of deforming the fret where the hammer hits, skewing the insert? If small iterative blows are used, distributed over the fret, isn't there lesser risk of deforming the frets? This basically then mimics using a press, to some extent. Then, when there is very little left to go for the frets into the fret board, like the last fractions of a m.m/inch I imagine that one or a few firmer blows would be the way to go to get it seated real well. Fewer blows at the end I imagine would not "disturb" the tang as much. However, in the picture I see that the fret has been overbent a lot. Maybe that does compensate for any plausible deformation from a single hammer blow. What do you think? 

Btw, a cool thing with a hammer is that it could allow for a non-uniform fret radius as opposed to when using a standard press caul. I have been playing around with the thought that it might be easier to wrap around the thumb at the bass end if the radius is a bit smaller there locally. Barre-chords could be harder though. Guess I have to try.

[ScottR]

First, you are correct in that frets must be radiused tighter (to a smaller diameter) than the fret board they are being installed in. This makes the ends squeeze the board instead of trying to pull away. Second, you are correct in thinking that one blow will not seat a whole fret. It will seat the section of fret being impacted by the blow. The force of the blow required has to do the the hardness and brittleness of the fretboard itself and the width of the slot in relation to the width of the tang and barbs and to a degree the size and material of the fret itself.

For instance, I recently fretted an ebony board with SS jumbo frets. Light taps would not seat the barbs deep enough and they would pull out when tapped at the other end of the fret....which would chip the ebony. A nice heavy blow was needed to seat the barbs deep enough to not pull out.

Softer more forgiving wood can be handled with lighter blows.

SR

[Gitarren]

Alright, this makes sense  All these nuances make guitar building so interesting. 

While at it,  do you prefer a hammer over a press in general? I can imagine that a proper hammering could set the fret in a bit firmer and deeper than a press, but that it should be a bit harder to use properly?

[ScottR]

5 hours ago, Gitarren said:

While at it,  do you prefer a hammer over a press in general? I can imagine that a proper hammering could set the fret in a bit firmer and deeper than a press, but that it should be a bit harder to use properly?

I would imagine the same.....having never tried a press. My guess is that a press would be easier to use. I do wonder what happens when your fretboard radius does not match the caul exactly when using a press.

One of the secrets to getting frets set deeply firmly into the board is to use a triangle file and bevel each slot. There is a rounded fillet where the tang joins the crown that can keep the fret from sitting down tight to the board in a non-beveled slot.

SR

[westhemann]

Using a press is easy enough. You just have to be careful and firm, while making sure you are lined up.

I have a press, but I hammer them in more often. Either way is fine. I can't say one is better than the other. You always hear people talk about deformed frets, but I can't imagine how careless or drunk a person would have to be to deform quality frets with a proper plastic tipped mallet.

 

Scott, if you don't have the exact right caul... say you are doing a compound board and it goes from 10" at the nut to 16" at the bridge... you would use the 10" to seat each fret at the ends first, then use a 16" to seat the middle. In effect, this works the same as having the fret over-radiused and pushes the tangs slightly sideways so they are less likely to pop up.

 

But like I say, hammer is just as good if you have a firm hand.

[ScottR]

On 12/1/2018 at 4:07 PM, westhemann said:

Scott, if you don't have the exact right caul... say you are doing a compound board and it goes from 10" at the nut to 16" at the bridge... you would use the 10" to seat each fret at the ends first, then use a 16" to seat the middle. In effect, this works the same as having the fret over-radiused and pushes the tangs slightly sideways so they are less likely to pop up.

Good to know, thanks.

SR