Current Build - Falcate Braced Multiscale OM cutaway
Re: Current Build - Falcate Braced Multiscale OM cutaway
Chladni test results:
T(1,1)1 - 104.5Hz
T(1,1)2 - 200Hz
Cross Dipole at 300Hz
T(1,1)3 - 235Hz
Long Dipole at 289Hz.
T(1,1)1 - 104.5Hz
T(1,1)2 - 200Hz
Cross Dipole at 300Hz
T(1,1)3 - 235Hz
Long Dipole at 289Hz.
Martin
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Re: Current Build - Falcate Braced Multiscale OM cutaway
Why do you say that? My guess is you will not need to do much to the back brace. When you lower the top with the bridge and strings I suspect the back will come down as well because it is coupled. If you want to hit 180 Hz you might want to be a bit higher when first strung as it will come down when you lower the T(1,1)3."Back does not appear to be coupling with the top at present."
Re: Current Build - Falcate Braced Multiscale OM cutaway
Hi John,johnparchem wrote:Why do you say that? My guess is you will not need to do much to the back brace. When you lower the top with the bridge and strings I suspect the back will come down as well because it is coupled. If you want to hit 180 Hz you might want to be a bit higher when first strung as it will come down when you lower the T(1,1)3."Back does not appear to be coupling with the top at present."
With the first top I had a T(1,1)2 at 175Hz and T(1,1)3 at 214Hz and it was appearing on the spectrum for the top. The back was obviously coupling. At the moment Im only seeing the 235Hz T(1,1)3 back peak when I tap the back and mic the back.
I did have a thought that bringing the T(1,1)2 peak down closer to 180Hz would result in the back coupling.
Martin
Re: Current Build - Falcate Braced Multiscale OM cutaway
Did a bit of thinning around periphery of lower bout and final tap test results as follows:
T(1,1)1 - 102Hz
T(1,1)2 - 194.7Hz
T(1,1)3 - 235Hz. A small peak on top FRC at 235Hz after thinning top.
The top has been shellaced and next job is the binding. Now wont that be fun
T(1,1)1 - 102Hz
T(1,1)2 - 194.7Hz
T(1,1)3 - 235Hz. A small peak on top FRC at 235Hz after thinning top.
The top has been shellaced and next job is the binding. Now wont that be fun
Martin
- Trevor Gore
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Re: Current Build - Falcate Braced Multiscale OM cutaway
Not as much fun as if you'd done a 3m back radius!kiwigeo wrote:...and next job is the binding. Now wont that be fun
Fine classical and steel string guitars
Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.
Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.
Re: Current Build - Falcate Braced Multiscale OM cutaway
Always up for a challenge.....!!Trevor Gore wrote:Not as much fun as if you'd done a 3m back radius!kiwigeo wrote:...and next job is the binding. Now wont that be fun
Martin
Re: Current Build - Falcate Braced Multiscale OM cutaway
The score so far:
Two Tassie Blackwood bindings bent...
Five broken lengths of binding on the floor
Four burnt fingers
Most fingers on both hands glued together with super glue at some stage during the day....
Two Tassie Blackwood bindings bent...
Five broken lengths of binding on the floor
Four burnt fingers
Most fingers on both hands glued together with super glue at some stage during the day....
Martin
- Trevor Gore
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Re: Current Build - Falcate Braced Multiscale OM cutaway
Try bending hotter (but don't char the wood), with water (just a little) only on the inside of the bend. There's no hurry. Tape them to the channels whilst they're still warm and they will cool with a better fit when you get to gluing them. A bit of work with a smoothing iron whilst they're taped on (not glued) will also help you close any gaps. I've done a good few of these over the years. Can't recall ever breaking a binding, though.
Now, that mad gidgee binding...THAT was bending challenge and a half!
Now, that mad gidgee binding...THAT was bending challenge and a half!
Fine classical and steel string guitars
Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.
Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.
Re: Current Build - Falcate Braced Multiscale OM cutaway
Hi Trevor,
Thanks for the tips. The iron is pretty hot but could probably go up a notch without charring the wood. As far as water goes Ive been giving the cutaway side bindings a soak in warm water prior to bending. Water is also applied to inside of bends if the wood starts to look too dry. Ill try using less water and more heat. Im taping the bindings to the guitar while they're warm and the plan is to run the sealing iron over them to get a perfect fit.
Due to the high breakage rate Ive opted to install the purflings at bottom of bindings when I glue bindings in. I may regret that decision but too much time was going to be spent gluing up perfs to bindings and then having the bldi things break. Let's see how we go....
Thanks for the tips. The iron is pretty hot but could probably go up a notch without charring the wood. As far as water goes Ive been giving the cutaway side bindings a soak in warm water prior to bending. Water is also applied to inside of bends if the wood starts to look too dry. Ill try using less water and more heat. Im taping the bindings to the guitar while they're warm and the plan is to run the sealing iron over them to get a perfect fit.
Due to the high breakage rate Ive opted to install the purflings at bottom of bindings when I glue bindings in. I may regret that decision but too much time was going to be spent gluing up perfs to bindings and then having the bldi things break. Let's see how we go....
Martin
- Trevor Gore
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Re: Current Build - Falcate Braced Multiscale OM cutaway
I've generally found that the purling lamination helps hold tricky wood together, to the extent that purfling lines top and bottom (the top one ultimately gets scraped off) can make the bending go easier. It's a similar concept that holds these bindings together as they are bent, but using inner and outer "purfling" as well as the bottom one I added. I use LMI white glue to glue the purflings on. I'm down to my last bottle, reserved only for that task. Apparently, Titebond 3 works well for this sort of job, but I've not tried it. All the cedar/rosewood guitars I've done with the figured blackwood bindings were bent with a B/W purfling attached. The B is fibre, so it really helps hold things together.kiwigeo wrote: Due to the high breakage rate Ive opted to install the purflings at bottom of bindings when I glue bindings in.
Fine classical and steel string guitars
Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.
Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.
Re: Current Build - Falcate Braced Multiscale OM cutaway
A temporary line of purfling on top of the binding...brilliant idea. Thanks for that.Trevor Gore wrote:I've generally found that the purling lamination helps hold tricky wood together, to the extent that purfling lines top and bottom (the top one ultimately gets scraped off) can make the bending go easier. It's a similar concept that holds these bindings together as they are bent, but using inner and outer "purfling" as well as the bottom one I added. I use LMI white glue to glue the purflings on. I'm down to my last bottle, reserved only for that task. Apparently, Titebond 3 works well for this sort of job, but I've not tried it. All the cedar/rosewood guitars I've done with the figured blackwood bindings were bent with a B/W purfling attached. The B is fibre, so it really helps hold things together.kiwigeo wrote: Due to the high breakage rate Ive opted to install the purflings at bottom of bindings when I glue bindings in.
Martin
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Re: Current Build - Falcate Braced Multiscale OM cutaway
Trevor
That comment produced a lightbulb moment for me. When I think back on my experience of hand bending bindings I have found some really easy - and now I think of it they were the ones with purfling strips attached. The only ones that I have ever snapped were "naked " ones. Sure, type of wood, figured grain, thickness - all important variables affecting the degree of difficulty - but I am now realizing that the glued-on purfling strip can be your friend.
FWIW, I have tried Titebond 3 and it worked out OK; didn't delaminate with the heat when bending
I think it is a good strategy to tape all 4 strips together and bend them all as one (OK, 2 at a time for a cutaway). And always use a metal slat behind the wood to reflect the heat and reduce the tendency to snap at one point.
Mark
That comment produced a lightbulb moment for me. When I think back on my experience of hand bending bindings I have found some really easy - and now I think of it they were the ones with purfling strips attached. The only ones that I have ever snapped were "naked " ones. Sure, type of wood, figured grain, thickness - all important variables affecting the degree of difficulty - but I am now realizing that the glued-on purfling strip can be your friend.
FWIW, I have tried Titebond 3 and it worked out OK; didn't delaminate with the heat when bending
I think it is a good strategy to tape all 4 strips together and bend them all as one (OK, 2 at a time for a cutaway). And always use a metal slat behind the wood to reflect the heat and reduce the tendency to snap at one point.
Mark
Re: Current Build - Falcate Braced Multiscale OM cutaway
OK so can we find out what formulation is the LMI White glue?
For all of us outside the US it would be good to find an alternative.
Dave
For all of us outside the US it would be good to find an alternative.
Dave
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Dave
Dave
Re: Current Build - Falcate Braced Multiscale OM cutaway
Titebond III has enough heat/moisture resistance to work on bindings. Ive used it in the past with no problems.
LMI instrument makers glue...as far as I know its an AR glue thats been tweaked. Ive used it in the past and found it pretty good.
LMI instrument makers glue...as far as I know its an AR glue thats been tweaked. Ive used it in the past and found it pretty good.
Martin
Re: Current Build - Falcate Braced Multiscale OM cutaway
F****k the blackwood bindings. 5 hours wasted trying to get the binding bent to radius of the cutaway.....even with the purfs glued on I ended up with splits in the blackwood and in the end the purfs gave up the ghost and disintegrated. Im going with Brazilian Rosewood bindings...the stuff bends like a dream after the bldi blackwood.
My f*****ng finger tips have turned black......I look like someone who's spent a lifetime on the fags.
My f*****ng finger tips have turned black......I look like someone who's spent a lifetime on the fags.
Martin
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Re: Current Build - Falcate Braced Multiscale OM cutaway
Give it a go with veneer softener...I seem to remember getting a result with some home made( I might be wrong, gettin' old, mate!)-"Homemade Softener - There's an age old veneer softener recipe of consisting of 3 parts water, 2 parts yellow glue, 1 part vegetable glycerin (which can be found at most pharmacies), and 1 part denatured alcohol. This concoction will soften veneer but it's sticky, messy, and hard to dry. It will also seal the wood cells which can have an effect on the wood's ability to accept a stain."(quoted) You may have to clean your bending iron afterwards. Bear in mind that it seals the wood, so stain won't penetrate afterwards.....
"Everything I say on the topic is based solely upon inexperience and assumption!"
Re: Current Build - Falcate Braced Multiscale OM cutaway
Hi Martin,
I found it possible to bend curly blackwood bindings to approx 50mm radius bend, on an iron without using a backing slat - about 200C taking it really slowly. Bent even better after soaking in fabric softener - I also tried veneer softener, but it seemed the results were no better than fabric softener (which is cheaper and more easily obtained). I don't know anything about the effect on finishing.
Thanks,
GregL.
I found it possible to bend curly blackwood bindings to approx 50mm radius bend, on an iron without using a backing slat - about 200C taking it really slowly. Bent even better after soaking in fabric softener - I also tried veneer softener, but it seemed the results were no better than fabric softener (which is cheaper and more easily obtained). I don't know anything about the effect on finishing.
Thanks,
GregL.
Re: Current Build - Falcate Braced Multiscale OM cutaway
I'm using supersoft, Im using a slat.....I'm trying everything except sending the bindings to the ATO for bending.
The radius is just too tight and the grain in the bindings isn't 100% right to prevent sections popping out adjacent to tightest radius curves.
The BRW looks just as nice on this guitar and it just bends a whole lot easier.
The radius is just too tight and the grain in the bindings isn't 100% right to prevent sections popping out adjacent to tightest radius curves.
The BRW looks just as nice on this guitar and it just bends a whole lot easier.
Martin
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Re: Current Build - Falcate Braced Multiscale OM cutaway
Oh what a luxury!! BRW!!! Much harder than blackwood for bindings as well. In fact, over twice the Janka!
"Everything I say on the topic is based solely upon inexperience and assumption!"
Re: Current Build - Falcate Braced Multiscale OM cutaway
Twice the Janke...half the hard yakka!!blackalex1952 wrote:Oh what a luxury!! BRW!!! Much harder than blackwood for bindings as well. In fact, over twice the Janka!
Martin
Re: Current Build - Falcate Braced Multiscale OM cutaway
Bindings and purfs all bent up. No more today...it's too bloody hot. Time for a Monteiths Summer Ale
Martin
Re: Current Build - Falcate Braced Multiscale OM cutaway
Top bindings glued in. Bindings plus purfs on bottom of bindings and two purfs behind the bindings all installed in one go.....call me Mr Octopus! The Luthier Tools binding cutting jig in the first photo....I've tried the other binding cutting jigs but Im just most comfortable with the Luthier Tools and the Porter Cable trimmer....it's something to to do with the fact I'm moving the trimmer around the guitar rather than moving the guitar around a stationary trimmer. Horses for courses...
Martin
Re: Current Build - Falcate Braced Multiscale OM cutaway
Back bindings in and the back scraped back. Had a few minor gaps that got filled by rubbing in ebony dust and then wicking in low viscosity CA glue.
Martin
- Trevor Gore
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Re: Current Build - Falcate Braced Multiscale OM cutaway
Hey Martin, how thick are those bindings? Maybe that's why the blackwood was so difficult?
Fine classical and steel string guitars
Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.
Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.
Re: Current Build - Falcate Braced Multiscale OM cutaway
That is looking fantastic ,I with interest am looking at the frequency part of this ,here is an interesting thing I see (guitar shop near by)someone picks up a well made guitar starts to play with it pressed against their chest I say move it away a little and listen to the change in sound wow what a difference ,just my silly observation .
John ,of way too many things to do.
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