Bracing on a King Billy Top

Talk about musical instrument construction, setup and repair.

Moderators: kiwigeo, Jeremy D

Post Reply
User avatar
Bob Connor
Admin
Posts: 3132
Joined: Mon Jul 09, 2007 9:43 pm
Location: Geelong, Australia
Contact:

Bracing on a King Billy Top

Post by Bob Connor » Thu Oct 28, 2010 8:07 pm

This is an OM that's going to end up gracing the office wall of Britton Brothers sawmill in Tasmania.

So bearing in mind that this is going to be as much a work of art as a musical instrument I allowed myself a bit of latitude in bracing the top and pulled together a whole lot of ideas that I have seen or thought would be useful.

The lower bout bracing is straight from some pics of Ervin Somogyi's guitars but I felt that it'd suit the King Wiliam Pine given it's usual lack of stifness along the grain. I also like the idea of not leaving great swathes of the lower bout unsupported. This sort of bracing allows more control over the ultimate stiffness of the top, both along and across the grain compared with the Martin style diagonal tone bars that I usually use.

The lattice work is surprisingly strong after glueing it all together. The lattice brace diminsions are 5mm x 3mm.

Bridge plate is a laminate of Osage Orange and Brazilian Rosewood and is much wider than I usually build. This again is to compensate for the lack of stifness in the KB top and to resist too much bridge rotation.

Working with the bridge plate is aother layer of King Billy around the sound hole to stiffen it up so that it won't dip. (you can't really see it from the pics)

The upper transverse brace is capped with 2mm Carbon Fibre courtesy of Mr Hickey.

The X-brace is slightly scalloped in the Martin Tradition.

The finger braces are angled slightly more across the grain than I usually do to add some stiffness.

I don't think KB is suitable for anything bigger than an OM but I've had some success with it on parlour guitars.

The X-brace fairly standard 6mm x 12mm.

I thought I'd throw these pics up to spark a bit of discussion about bracing and why you do certain things to achieve your objectives
FIL26128.JPG
FIL26128.JPG (116 KiB) Viewed 22014 times
FIL26129.JPG
FIL26129.JPG (120 KiB) Viewed 22014 times
FIL26130.JPG
FIL26130.JPG (3.93 MiB) Viewed 22014 times





_________________
Bob, Geelong
_______________________________________

If Becks are a sponsor next year I guess we'll just have to give East Augusta a miss.

User avatar
Kim
Admin
Posts: 4376
Joined: Wed Sep 26, 2007 8:32 pm
Location: South of Perth WA

Re: Bracing on a King Billy Top

Post by Kim » Thu Oct 28, 2010 8:07 pm

Very cool Bob, I am lik'in that configuration and feel the whole top looks well balanced in it's lay out.

Glad the CF got to you OK

Cheers

Kim
_________________
ĆϾϿƆ
_(ӧ) ∩
_ڔ ڔ
Pull me Finga

User avatar
woodrat
Blackwood
Posts: 1155
Joined: Tue Nov 25, 2008 6:31 am
Location: Hastings River, NSW.
Contact:

Re: Bracing on a King Billy Top

Post by woodrat » Thu Oct 28, 2010 8:08 pm

Very nice Bob...I get an arachnid kind of feeling from the photos, perhaps you could call it spider bracing!
I haven't seen Ervins books yet but I imagine there are lots of things that many of us wouldn't have tried before and maybe some stuff we wouldn't have seen either.
The CF over the Upper brace looks like a good idea. One to file away for next build.

Cheers


John
_________________
Say No to Mediocrity!

User avatar
Nick
Blackwood
Posts: 3641
Joined: Thu Feb 26, 2009 11:20 am
Location: Christchurch, New Zealand
Contact:

Re: Bracing on a King Billy Top

Post by Nick » Thu Oct 28, 2010 8:08 pm

Cool build Bob. I'm liking the look of the Lattice, looks like it will definitely stiffen up the lower bout without stopping the resonance due to it's mass I'm guessing. Didn't realise King Billy was weak across the grain. Tim packed my auction winning Bunya between two bits of KB so will have to have a closer fondle of that to see what you talk of. Wink
Nice tidy work as always too.
_________________
A handmade Guitar for $300 ? Phftt. Sure, give me a chunk of wood, a hammer & some 6 inch nails & I'll see what I can knock up for ya.

Nick Oliver
www.oliver-guitars.com

User avatar
John Steele
Blackwood
Posts: 152
Joined: Fri Mar 06, 2009 4:58 pm
Location: Wilson, NY. 14172
Contact:

Re: Bracing on a King Billy Top

Post by John Steele » Thu Oct 28, 2010 8:09 pm

Hey Bob;
Your wood looks a lot like the coastal redwood here in CA. tight grain, light, but weaker than spruce. I've only built 3 guitars out of redwood, my 2nd, 3rd, and one of the L1's I posted here a while back. If your King Billy is like I think it is, I think you're spot on. Thicker top with lots of light weight braces seems the way to go. You can always mess with the top thickness after its built if you need to loosen it up. Osage is from over here in the states, back east around the Appalachian Mts I believe. Heard good things about it for instruments and always keep an eye out for some. Bummer the guitar is to hang on the wall. Bet it'll be a good instrument.
J
_________________
“Most people are amazed when they think about how stupid the average American is, until they realize that the other half is even more stupid than that!"

-George Carlin

User avatar
Allen
Blackwood
Posts: 5252
Joined: Thu Oct 11, 2007 5:39 pm
Location: Cairns, Australia
Contact:

Re: Bracing on a King Billy Top

Post by Allen » Thu Oct 28, 2010 8:09 pm

It's a really interesting design Bob.

How does it tap tone sound now that you've got it shaped? Is it what you hoped and expected?

I imaging all those brace ends in the lower bout are going to end just shy of the linings?

What did you use to glue the CF on to the Upper Transverse Brace?
_________________
Allen R. McFarlen

liam_fnq
Blackwood
Posts: 596
Joined: Tue Jun 02, 2009 4:54 pm

Re: Bracing on a King Billy Top

Post by liam_fnq » Thu Oct 28, 2010 8:10 pm

lookin' good bob.

couple of questions though. (you knew they were coming Laughing )

how does the stiffness of the latticed area relate to a traditionally braced soundboard.

also, what are your thoughts on cross grain gluing vs. with grain gluing of the soundhole patch. I would have thought that cross grain gluing would give a stronger result with greater resistance to the downward force of the fingerboard extension.

very interesting stuff bob.

liam.

User avatar
Bob Connor
Admin
Posts: 3132
Joined: Mon Jul 09, 2007 9:43 pm
Location: Geelong, Australia
Contact:

Re: Bracing on a King Billy Top

Post by Bob Connor » Thu Oct 28, 2010 8:10 pm

Nick - all of the King Billy I've cut hasn't been too stiff cross grain. I don't worry too much about cross grain floppiness - you can build stiffness into it.
I think a lot of the problem with KB is that most of it is cut from boards - not split from a round of the tree, so most of what we see suffers from runout.

John - it's not as brittle as redwood and doesn't quit have the same sustain.
This top was sounding quite good (ie quite good sustain) until I glued the upper transverse and the soundhole patch in. That dampened it down a bit.

I don't think tap tone gives you the full story though. I'll reserve judgement 'til the strings go on.

I am going to glue the top on first and do some more playing with it before I commit to the bracing.

Allen - it taps like the other KB guitars I've built. At present it sustains for about 2 seconds all over the lower bout. I'd just like to tweak it to get it a bit longer. I was concerned about this one because of the larger size but I think it'll be OK when the strings go on.

The CF was glued with Araldite and yes there won't be any tucking of braces south of the soundhole.

Liam - I think there's about the same mass and weight in braces on the lower bout but I feel that the lattice is stiffer and allows you to distribute that more evenly over the lower bout.

With the soundhole patch the cross grain will be stronger but in this case I don't think it matters too much as I've got the two "A" braces that I don't normally use as well as the patch, so it'll be a lot stronger than what I have been doing. Bearing that in mind I cut the patch with the same grain orientation as the top.
_________________
Bob, Geelong
_______________________________________

If Becks are a sponsor next year I guess we'll just have to give East Augusta a miss.

User avatar
John Maddison
Blackwood
Posts: 356
Joined: Tue Jun 03, 2008 11:15 pm
Location: Albany, Western Australia
Contact:

Re: Bracing on a King Billy Top

Post by John Maddison » Thu Oct 28, 2010 8:11 pm

Hi Bob
Beautifully engineered; the soundboard in itself could hang on a wall as a work of art. Which species did you cut the braces from?
_________________
John

User avatar
Craig
Admin
Posts: 1090
Joined: Wed Sep 26, 2007 10:08 am
Location: N.S.W. in the bush

Re: Bracing on a King Billy Top

Post by Craig » Thu Oct 28, 2010 8:11 pm

Great design Bob and well thought out. It's got a lot going for it with the A Frame and C.F. capping on the transverse. Nice work on the lattice bracing too . What dimensions are the A Braces and transverse ?
_________________
Craig Lawrence

User avatar
Bob Connor
Admin
Posts: 3132
Joined: Mon Jul 09, 2007 9:43 pm
Location: Geelong, Australia
Contact:

Re: Bracing on a King Billy Top

Post by Bob Connor » Thu Oct 28, 2010 8:12 pm

John - the braces are Red Spruce but the lattice was cut from Engelmann.

Craig - the UTB ended up 12mm square. The A braces are 6mm x 12mm.
_________________
Bob, Geelong
_______________________________________

If Becks are a sponsor next year I guess we'll just have to give East Augusta a miss.

Hesh1956
Blackwood
Posts: 1420
Joined: Thu Sep 27, 2007 9:58 am

Re: Bracing on a King Billy Top

Post by Hesh1956 » Thu Oct 28, 2010 8:13 pm

WOW Bob that is one beautiful job of bracing a top.

I agree too that there is a balance or symmetry that just looks like the guitar will sound killer.

Keep us posted on how she sounds - I suspect that you may not wanna give this one up.

User avatar
J.F. Custom
Blackwood
Posts: 779
Joined: Fri May 01, 2009 9:13 pm
Location: Brisbane
Contact:

Re: Bracing on a King Billy Top

Post by J.F. Custom » Thu Oct 28, 2010 8:13 pm

G'day Bob,

Interesting design there and lovely crisp work.

I've got a couple of king billy tops unused as yet so will follow the outcome of this experiment with interest and kudos for doing the experiment in the first place when it can be more secure to do what we already know.

One question - the lattice work. The joins appear to my eyes to have three one way, one another - hopefully you follow what I mean. As in - each individual component of the lattice is not over/under in the joinery - with one brace being under/under, another over/over, the final two under/over. Any reason for this or just the way you happened to cut them? Would it make any difference in this design or possibly larger lattice work such as Smallmans design, to cut the joins over under at each point all the way through? Added strength or stability or distribution of stresses? Your thoughts?

Cheers,

Jeremy.
_________________
J.F. Custom Guitars
www.jfcustom.com.au

Cannons Don't Kill People...
Pirates with Cannons Kill People.

User avatar
Allen
Blackwood
Posts: 5252
Joined: Thu Oct 11, 2007 5:39 pm
Location: Cairns, Australia
Contact:

Re: Bracing on a King Billy Top

Post by Allen » Thu Oct 28, 2010 8:14 pm

Another question Bob. Did you press the lattice in, or has it had a radius put on the bottom prior to glueing it to the top?
_________________
Allen R. McFarlen

User avatar
Bob Connor
Admin
Posts: 3132
Joined: Mon Jul 09, 2007 9:43 pm
Location: Geelong, Australia
Contact:

Re: Bracing on a King Billy Top

Post by Bob Connor » Thu Oct 28, 2010 8:14 pm

I wondered whether anyone would notice that Jeremy Very Happy

That was just the way It happenned.

Because of it's symmetrical design I don't think it would r eally matter which way you cut the lap joints.

Allen - the only brace that I radius thes days is the X brace. I put a a small amount of radius on the upper transverse as well (opnly about 40mm on each end)
_________________
Bob, Geelong
_______________________________________

If Becks are a sponsor next year I guess we'll just have to give East Augusta a miss.

User avatar
Allen
Blackwood
Posts: 5252
Joined: Thu Oct 11, 2007 5:39 pm
Location: Cairns, Australia
Contact:

Re: Bracing on a King Billy Top

Post by Allen » Thu Oct 28, 2010 8:15 pm

I recall reading in one of Graham MacDonald's books, or maybe an article that he did, that he found that the lattice could be lapped, or just butt jointed. He didn't notice any difference in the way it worked.

Are you talking about 40 mm scallops on the end of the upper transverse brace Bob? I was noticing in Ervin's book that at least in one image he doesn't even do that, rather uses them full height and even puts braces at the ends where they are attached to the rims.
_________________
Allen R. McFarlen

User avatar
Bob Connor
Admin
Posts: 3132
Joined: Mon Jul 09, 2007 9:43 pm
Location: Geelong, Australia
Contact:

Re: Bracing on a King Billy Top

Post by Bob Connor » Thu Oct 28, 2010 8:15 pm

I'd say they were closer to 30mm Allen.

The UTB beam would work better if it didn't have the scallops in the end for sure. I'm just not sure if it'd be overkill.
_________________
Bob, Geelong
_______________________________________

If Becks are a sponsor next year I guess we'll just have to give East Augusta a miss.

Rick Turner
Blackwood
Posts: 311
Joined: Sun Jan 13, 2008 10:22 am
Location: Santa Cruz, Ca.
Contact:

Re: Bracing on a King Billy Top

Post by Rick Turner » Thu Oct 28, 2010 8:16 pm

Very nice, Bob.

We do that carbon fiber cap on the upper transverse braces on our Compass Rose Ukes, too, and it's great for keeping the upper bout top under control.

Beautiful craftsmanship, too...
_________________
Rick Turner
Guitar Maker, Experimenter, Diviner
www.renaissanceguitars.com
www.d-tar.com

User avatar
Clancy
Blackwood
Posts: 620
Joined: Wed Dec 17, 2008 10:26 am
Location: Canberra

Re: Bracing on a King Billy Top

Post by Clancy » Thu Oct 28, 2010 8:17 pm

Quote:
I recall reading in one of Graham MacDonald's books, or maybe an article that he did, that he found that the lattice could be lapped, or just butt jointed. He didn't notice any difference in the way it worked.

This is the lattice work as described in Graham's book - unless I did it wrong Confused
img~

User avatar
Allen
Blackwood
Posts: 5252
Joined: Thu Oct 11, 2007 5:39 pm
Location: Cairns, Australia
Contact:

Re: Bracing on a King Billy Top

Post by Allen » Thu Oct 28, 2010 8:17 pm

One of yours Craig?

Great looking top.
_________________
Allen R. McFarlen

User avatar
Dominic
Blackwood
Posts: 1098
Joined: Thu Jan 10, 2008 8:58 am
Location: Canberra

Re: Bracing on a King Billy Top

Post by Dominic » Thu Oct 28, 2010 8:18 pm

Quote:
The upper transverse brace is capped with 2mm Carbon Fibre courtesy of Mr Hickey

Bob, can you tell us who Mr Hickey is? Can't find a reference to him.
Cheers
Dom
_________________
You can bomb the world to pieces,
but you can't bomb the world to peace!

User avatar
John Maddison
Blackwood
Posts: 356
Joined: Tue Jun 03, 2008 11:15 pm
Location: Albany, Western Australia
Contact:

Re: Bracing on a King Billy Top

Post by John Maddison » Thu Oct 28, 2010 8:18 pm

Dominic wrote:
... can you tell us who Mr Hickey is? ...
Mr H.'ll probably chime in at some stage; he might be very busy right now knocking the top off a cold one Rolling Eyes.
_________________
John

Last edited by John FM on Mon Dec 21, 2009 8:56 pm; edited 1 time in total

User avatar
kiwigeo
Admin
Posts: 10587
Joined: Sat Sep 29, 2007 5:57 pm
Location: Adelaide, Sth Australia

Re: Bracing on a King Billy Top

Post by kiwigeo » Thu Oct 28, 2010 8:19 pm

Mr Hickey = our own Kim. Maker of fine guitars and a dab hand also at the English language.

User avatar
Allen
Blackwood
Posts: 5252
Joined: Thu Oct 11, 2007 5:39 pm
Location: Cairns, Australia
Contact:

Re: Bracing on a King Billy Top

Post by Allen » Thu Oct 28, 2010 8:21 pm

He's a reclusive curmudgeon that lives on the wild south west coast of WA. Doesn't talk much, and only grants interviews after careful consideration of ones path on lutheier enlightenment.

How Bob managed to to gain favour is truly beyond me. Must have got the Hickey in a moment of weakness.
_________________
Allen R. McFarlen

User avatar
John Maddison
Blackwood
Posts: 356
Joined: Tue Jun 03, 2008 11:15 pm
Location: Albany, Western Australia
Contact:

Re: Bracing on a King Billy Top

Post by John Maddison » Thu Oct 28, 2010 8:21 pm

Allen wrote:
He's a reclusive curmudgeon ... Doesn't talk much, and only grants interviews after careful consideration ...
His friends call him Mr Hickey, while most of us have to call him 'Sir'. Titles such as 'Oracle' or 'Mystical Master' can also find favour Wink.
_________________
John




In this thread this is the last re-constructed message by the ANZLF helping team. For more information click here.

Post Reply

Who is online

Users browsing this forum: No registered users and 97 guests