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fungusgeek
12-02-2013, 10:46 AM
A recent posting (see "String Theory) contained an interesting document as to how a plucked Ukulele string creates sound. What was surprising to me was that this doc indicated that the plucked string motion which I would think would at least initially be 'up-and-down' (perpendicular to the string length) turns into a longitudinal vibration (along the length of the string) which causes the bridge to 'rock' and turns the sound board into a 'pump'.

If the sound is created by the 'rocking' of the bridge (as opposed to the string driving the bridge/soundboard up-and-down) then it would seem that any slight looseness of the saddle in the bridge slot would greatly damp the sound production, since the saddle could rock without causing the bridge to 'pump' the soundboard.

I was always under the impression that a saddle (bone etc.) was just a press fit into the bridge. Is this correct? Is it a very tight press fit?
Does anyone glue the saddle in to make the saddle/bridge a monolithic thing so that there would be no 'rocking' of the saddle so that the 'pump' action would be maximized?

resoman
12-02-2013, 11:12 AM
Check out the Roger Siminoff book "The Luthier's Handbook". While it doesn't tell you how to build it covers the why and how things happen with instruments. I thought it is pretty good and I've read it over a couple of times.
For me, I make my saddles fit pretty snug. Not exactly what I would call a press fit but not a slip fit either. I make it press enough to where it takes a little work to place the saddle but not so tight that you are deflecting the top very much. I never glue a saddle in except on a "dobro" guitar where I make them pretty durn tight and then wick a drop of superglue between the spider and the inserts.
This is what works for me but I bet others have a different opinion which is to be expected. ;)

BlackBearUkes
12-02-2013, 06:28 PM
I always make the saddle so it can be removed and changed without having to resort to pliers. If the saddle is too tight, it can crack the bridge slot if the humidity changes. A snug fit is best and never use glue.

Timbuck
12-02-2013, 08:55 PM
On the old Martin sopranos ..the saddle was glued in..but now they make it non glued, mainly due to customer preference.

KentF
12-03-2013, 02:26 AM
Were those old Martin bridge slots open on the ends? I had a vintage reissue Martin guitar, an OM-18v, and it was a through slot with a glued in saddle. I believe later models of that guitar were only pressed in. I assumed they were glued to keep the saddle from moving side ways.

Beau Hannam Ukuleles
12-03-2013, 10:24 AM
yep- "through saddles" were all glued in, (old) guitars as well. Remember those were pre cheap undersaddle pick up days. I've never bothered to glue in a through saddle as the only time it could get lost is on restringing.

Press fit tightness, one shouldn't have to struggle with getting a saddle out/in, but it shouldn't flop into the slot either.

BlackBearUkes
12-03-2013, 01:54 PM
yep- "through saddles" were all glued in, (old) guitars as well. Remember those were pre cheap undersaddle pick up days. I've never bothered to glue in a through saddle as the only time it could get lost is on restringing.

Press fit tightness, one shouldn't have to struggle with getting a saddle out/in, but it shouldn't flop into the slot either.

I have to disagree that all "slot through" style saddles were glued in. I have worked on many old Martins, Washburns (not the new junk) with a pyramid or similar bridge designs and most of these guitars did not have glued in saddles, just tightly fitted. Some owners of these guitars did use glue on them but it was out of ignorance. If the saddle fits well, not too tight or sloppy, there is no reason to glue it in no matter what the design.