Wallnut Density for SS Falcate Bridge

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Mitch Lees
Beefwood
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Location: Findhorn, Scotland

Wallnut Density for SS Falcate Bridge

Post by Mitch Lees » Tue Aug 06, 2019 12:38 am

I am building a SS 12 Fret Falcate as per the book and plans - contemporary bridge design exactly as Vol 2 Fig 20-3. Trying to get the bridge weight below 20gms. So far have only achieved 23 gms. I have yet to shape the bottom to fit the guitar top, but this will only require about .5mm to be removed from the centre - I may save a gm or so. Saddle slot will be routed later when bridge is fitted, but the saddle will increase the wt anyway. One layer of CF used - CF spec as per the Book and I was careful not to use too much West System resin.

My question is about the density of the wallnut used for the example in Book 2. My American Wallnut has a density of 730 Kg/cubic meter, which seems very dense for wallnut - maybe it is a particularly dense piece or maybe it is not wallnut after all! (but I think it is). I am going to try and source some more walnut and have another go, but it would help to have an idea of the sort of density you guys have used for these light bridges. I am in the UK so cannot get Australian woods.

Grateful for any advice
Mitch

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Trevor Gore
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Re: Wallnut Density for SS Falcate Bridge

Post by Trevor Gore » Tue Aug 06, 2019 9:23 am

I've used between 550 and 650 kg/m^3. Black walnut has a wide spread in density, but 730Kg/m^3 is on the high side. Bootle (a wood reference) quotes 600 kg/m^3 for American Black walnut; the Wood database quotes 610 kg/m^3 as an average.

Mitch Lees
Beefwood
Posts: 20
Joined: Mon Jan 08, 2018 3:54 am
Location: Findhorn, Scotland

Re: Wallnut Density for SS Falcate Bridge

Post by Mitch Lees » Tue Aug 06, 2019 3:47 pm

Thanks Trevor,

I have found another piece in the wood shed. It comes in at 556 which is nearer the mark. Not as tight grained as the previous one, and just off quarter, but I will make another bridge today and see if I can get under 20 grams.

Regards
Mitch

Mitch Lees
Beefwood
Posts: 20
Joined: Mon Jan 08, 2018 3:54 am
Location: Findhorn, Scotland

Re: Wallnut Density for SS Falcate Bridge

Post by Mitch Lees » Fri Aug 09, 2019 5:45 pm

New bridge is 17.5 gms - success!

Dave M
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Location: Somerset UK

Re: Wallnut Density for SS Falcate Bridge

Post by Dave M » Mon Aug 12, 2019 2:19 am

Good stuff Mitch. I haven't been able to get my rosewoods below about 23 - 24 gm. I have stuck with it so far to keep the aesthetic right with the fretboard.
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Dave

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