Crawls Backward (When Alarmed)

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Saddle Relocation on Gretsch Soprano Ukulele, Phase Two

 I believe I mentioned some new tools I had procured for the work on the Gretsch ukulele bridge.  Here's Tool Number Two.  It's a Dremel router base from Stew-Mac.  Dremel themselves make a router base, but the reviews I read were not good.

So I went with this one.  It costs a bit more (BIT more, get it?), but I think it's worth it.

For one thing, it's made of all aluminum, where the Dremel is plastic.  Second, there is a nice setup for depth adjustment.  Should be perfect for making a saddle slot.

I had previously done a test using a piece of bone behind the original saddle to get a general idea of where I'd need to relocate the saddle to.  I knew I'd need to move it back, but now I need to measure and determine the exact scale length.

So I measured from the nut to the center of the 12th fret (the fret slot, more accurately) and guess what?  It's 6 13/16ths inches!  I was assuming the scale was 13.5 inches and it's not.  It's 13 5/8, or converted to decimal, 13.625 inches.  Hmmm. 

I got some helpful advice from Sven at Argapa, and also read Kawika Hurd's compensation article.  I knew I'd need to add a few millimeters to the scale length to get it to intonate.  I also decided to convert my measurements to millimeters, since I find metric measurements a whole lot easier to work with on this sort of thing.

Using the very handy Stew-Mac converters and calculator, I find that for my scale length of 346.07mm, my bridge placement should be 348.11mm.  I want to add a couple of millimeters to that so I have some saddle width to work with to file some compensation as needed.

Bottom line is that if I place a new saddle so it overlaps that 348mm mark by a couple mm, I have run out of bridge width.

Here's a hunk of bone blank in about the location I want.  If I put a saddle there, the back angle down to the existing string slots will be way too great.  There will be a tendency to break strings, for one thing, and I think the downward pressure will wear the saddle quickly.

The obvious answer is that the whole bridge needs to be relocated.

I'm thinking that if I take the bridge off, the part of the top that's underneath is probably not going to look too pretty.  I'll see when I take it off, but that's my guess.

Looking around the dungeon, I see a nice long piece of mahogany bracewood I just ordered from LMI for another upcoming project.  Light bulbs go off in my head.  Hmmm, I ponder.

I am thinking I will make/fabricate a new bridge!  Just like the original, but a bit wider so it covers the old joint and gives me the length I need.

Good idea, but can I pull it off?  I am not the world's most skilled woodworker.  On the other hand, how hard can it be?  Most of the surfaces are square - not a lot of fancy curves.

The LMI label on the wood.  I suppose if I actually use this for an actual instrument part, I am doing actual lutherie.  Whoo hoo!

 
 
 
 

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