Official Luthiers Forum!
https://www.luthiersforum.com/forum/

Defending Tradition, Bridge plates, Braces, Serviceability
https://www.luthiersforum.com/forum/viewtopic.php?f=10101&t=45382		 Page 1 of 2
Author:  Hesh [ Thu Mar 19, 2015 12:22 pm ]
Post subject:  Defending Tradition, Bridge plates, Braces, Serviceability
The first guitar that I ever built was a Stew-Mac dreadn*ught kit and that's what started all of the madness for me including a career change, moving to have a better shop that happened to have a house over it, and lots of spending on all sorts of tools, etc.

I recall from the kit back in the day that the bridge plate was inlet into the two lower X legs. I also recall asking about this on this very forum about a year later. The replies that I received pointed me in the direction of serviceability and the notion that at times bridge plates may have to be replaced....

These days as a partner is a very busy repair business I know all too well that bridge plates do at times need to be serviced, replaced, capped, etc.

Others told me back then that because bridge plates may need servicing inletting may not be a good idea. Later in life pro repair people told me the very same thing. These days as someone who has to remove and replace bridge plates at times I now know this to be a valid concern.

Then along comes my introduction to Ervin Somogyi and my personal fascination with him as a Luthier as well as the superb instruments that he is best known for. When I got a peek at Ervin's bracing he was coupling some tone bars with the bridge plate. I again wondered if this might have serviceability implications in so much as the plate was now more difficult, not impossible mind you...., to remove.

Around this time someone introduced the notion that braces too can perform as meridians for vibration and that braces are not just another structural support.

Of course all along there were numerous glue threads..... where some proclaimed the superiority of HHG and liked it so very much that they may be seeking marriage equality with HHG these days.... We discussed the glass like, very hard nature of HHG and how some believed that it transmitted vibration better than say glues such as epoxy.... Dampening came into play and then along comes CF.... laminated braces.

Now no disrespect intended, ever, to Trevor and my hat's off to ya for your superb instruments AND the innovative approach that you have had based on science and engineering to guitar building. My entire life I was a technologist of sorts very nearly to the point of helping Al Gore invent the Internet (not really, it just came to mind...:)).

Falcate bracing is attractive to me too mostly because the reviews that I have read of Trevor's guitars are all glowing with a common theme, more volume, great tone!

Now if you have hung in this thread long with me and any of this is making any sense at all good for you - here's the point.

Should we not be concerned that a falcate braced instrument has the bridge plate mounted beneath the two primary longitudinal braces or the equivalent of the X brace on a traditionally braced guitar? If the plate ever needs servicing it's going to be a bear if not nearly impossible to get the plate off....

Another concern that I have as well is the nature of the bracing being curved. I see failed guitars every single day and no I am not looking at my personal collection either.... ;) I know how a blow can pop a brace and how often this actually happens in the real world. From the fat guy who got drunk and sat on his ax to the jealous lover who pitched the Martin down the stairway trying to hit her exiting lover we see it all. Admittedly the stories are more fun than the repair work but I'll save that for another day.

So again not picking on Trevor but I have concerns that curved braces when they take a hit or impact are going to do what curved structures try to do and that is rotate. Maybe this is by design to help get the bridge plate off? :)

Anyway with great personal respect for Trevor I have to ask the following:

1) With falcate bracing how is the bridge plate removed?

2) Have any of your instruments been damaged as they might be in time by players and what resulted was a popped brace, if so which braces, etc.

3) Can't know because I have not bought your books (yet) but is there any concern that the CF laminations and the likely need for CF laminations in curved structures and the glue required to laminate the braces have a dampening affect on the ability of the braces to transmit vibration?

4) I use CF in my UTB but HHG to glue the UTB to the top. Again I don't have the books so what glues are you recommending to glue bracing, HHG?

Thanks in advance!
Author:  SteveSmith [ Thu Mar 19, 2015 1:14 pm ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
Hi Hesh - how's the meds? You sharing 8-)

I've built one falcate braced guitar and it did work well. A bridge plate repair should be less likely in this design. The way I did mine mostly followed the guidelines in the "Book". On mine, the bridge was made with carbon-fiber cloth laminated in between the top and bottom halves and the same carbon-fiber cloth was laminated between the bridge plate and the top. I think this will likely eliminate cracking and probably make it pretty darn hard to damage anything with the pins. I'm sure some player out there will find a way to tear one up. I wouldn't want to have to try and replace that bridge plate.
Author:  John Arnold [ Thu Mar 19, 2015 1:32 pm ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
I don't remove nearly as many bridgplates as I used to. Part of that comes from repairing older Martins, which have the bridgeplate tucked under the X-braces. Repairing the pin holes is usually pretty simple. I tape over the holes on the bridgeplate and fill the holes by alternately dropping thin CA and locust dust in them. After it hardens, I remove the tape and redrill and ream the holes.
Author:  Hesh [ Thu Mar 19, 2015 2:24 pm ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
SteveSmith wrote:
Hi Hesh - how's the meds? You sharing 8-)

I've built one falcate braced guitar and it did work well. A bridge plate repair should be less likely in this design. The way I did mine mostly followed the guidelines in the "Book". On mine, the bridge was made with carbon-fiber cloth laminated in between the top and bottom halves and the same carbon-fiber cloth was laminated between the bridge plate and the top. I think this will likely eliminate cracking and probably make it pretty darn hard to damage anything with the pins. I'm sure some player out there will find a way to tear one up. I wouldn't want to have to try and replace that bridge plate.


Hey Steve! I'm off those.... meds now and stuck with good ole Tylenol and it sucks.... Thanks for asking! :D

You just answered one of my questions and thanks too for that. So what you are saying is that the plate is laminated and the bridge too likely eliminating the common bridge plate killer of a cracked or split plate? Because of the laminations this is unlikely to happen? Sounds right to me too.

The next common issue for bridge plates is when a bridge lifts in the back the plate no longer has the benefit of it's big brother brace, the bridge and can crack, split, come loose too. Mind you this is with string tension present as well pushing in front of the bridge down and pulling up on the belly area.

I still see the possibility of with a bridge lift the plate becoming unsupported and perhaps distorting in it's efforts to counter the pull of the strings and deformation of the top. A laminated plate might not and likely will not split but it still can distort I would suspect. If it does it would need to be replaced or this distortion may contribute to another bridge lifting since the under lying support for the bridge is distorted.

Anyway it would be nice to be able to push the clock 40 years ahead and see how this bracing system does in time.

Hey john: We repair far more plates than we replace too but we do replace them and replaced one for an OLFer several months ago.

What we do is make composite plugs on the lathe that are spruce on top of what ever the bridge plate material is, maple, EIRW, etc. We also turn our plugs so that the grain orientation is the very same as the top and won't use end grain. The two part plug is hoped to come apart as two parts if anyone ever wants or needs to replace the bridge plate. Our thought is that the plug will separate too. But you can see that even with plugging and redrilling pin holes the entire reason for the composite, two part plug and the extra effort required is so the the instrument remains serviceable well into the future should it need a bridge plate repair again.
Author:  Jeff Highland [ Thu Mar 19, 2015 7:05 pm ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
Hesh wrote:
Anyway with great personal respect for Trevor I have to ask the following:

1) With falcate bracing how is the bridge plate removed?

2) Have any of your instruments been damaged as they might be in time by players and what resulted was a popped brace, if so which braces, etc.

3) Can't know because I have not bought your books (yet) but is there any concern that the CF laminations and the likely need for CF laminations in curved structures and the glue required to laminate the braces have a dampening affect on the ability of the braces to transmit vibration?

4) I use CF in my UTB but HHG to glue the UTB to the top. Again I don't have the books so what glues are you recommending to glue bracing, HHG?

Thanks in advance!


Hi Hesh, Having built 6 Falcate braced guitars IMHO

1) Removing the bridge plate would be impossible, but I cannot imagine it ever "failing" through splitting due to the lamination of CF fabric and the two central falcate braces spanning it. Ball end wear would be addressed by insitu repair or preferably avoided by using unslotted pins
2) The chances of a popped brace end are minimised by the use of a fishtail of CF entending onto the soundboard from the brace ends
3) The high strength epoxy I use is every bit as hard as HHG, dampening does not seem to be an issue.
4) The braces in this method are not laminated a la Proux , but capped and underlayed with CF strands As such, epoxy is used for all soundboard bracing.
Author:  uvh sam [ Fri Mar 20, 2015 6:15 am ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
Hesh,
Not every guitar is a Martin. Some would say martins are "tanks" compared to many hand makers instruments today. It is for this reason that I would say that the "new" style of building may require a different approach in repairing than the old way. Instead of pulling a bridge plate, the repair may mean replacing the top! This may sound radical to us, but I have heard from many players that they do not have the time or patience for a guitar to "open up" in ten years, which has pushed many builders to build lighter and lighter which will certainly create new problems we didn't see with the traditional design of guitars.
I do not have sympathy for the player who beats his guitar around and knocks braces loose, cracks the top, or allows it to dry out, so if you want a guitar that you can do that to, perhaps a delicate handmade guitar is not for you.
As for the falcat/cf style of building, the big thing to remember is that many of the problems you may I counter with the traditional build model are due to cold creep over time. Supposedly the carbon fiber prevents this so I would wager bridge plate repairs as we are used to them may not be a problem in the future for those guitars.
All of this goes to a greater question of how long a guitar should last. If it will last a thousand years but sound terrible the whole time, who cares how stable it is.
These are questions for the maker to answer as they will most likely be responsible n the event of a catastrophic failure.
The bright side is that as a whole, the hand maker market s so small that the number of guitars the average repair guy will see that have falcate bracing is so small, it may not be worth losing sleep over. Just keep on working on those martins, that's where the money is anyway
Author:  Hesh [ Fri Mar 20, 2015 6:55 am ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
Thanks guys, some really excellent thinking and posts here, Steve, John, Jeff, and Sam.

From Jeff's and Steve's post I already decided that replacing a plate on a falcate braced instrument may not even be necessary. John brings up repairing over replacing and that's most certainly an option if the plate does not split and a laminated plate likely would never split.

Sam has me, correctly I would add, reminded that these are not Martins and repair as we know it may need some new thinking to deal with falcate braced instruments. I also appreciated what Sam said about the fact that there is a market for instruments that sound good now, today, and won't need a decade to naturally open up. Kind of like anything high performance, there may be down sides but immediate gratification might not be one of them.

I still do see the possibility of braces popping after all the guy who gets drunk and sits on his guitar likely is a nondiscriminatory guitar abuser and would not cut a Falcate braced instrument any slack either... Since epoxy has been used and when regluing we are working blind in the box, often that means that epoxy would likely be the choice for regluing braces as well since the residual epoxy from when it was built can't be completely removed. No biggie, just different and requiring as Sam said a different approach. Still thinking here how to not have the epoxy glue the clamps since I think that epoxy will attach to waxed paper which is often what's used to shield clamps and magnets from Titebond and HHG. Not sure on this though, epoxy and waxed paper.

To the guys who have built a falcate braced instrument what epoxy did you like?

Back to bridge plate distortion. I was looking at some pics of Falcate braced guitars last night and where the major braces cross the bridge plate they are at their thickest which seems to me would likely help the bridge plate resist distortion over time too.

Thanks for the insights guys, much appreciated. Wondering when we will see our first Falcate braced instrument in for a set-up.
Author:  meddlingfool [ Fri Mar 20, 2015 8:11 am ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
Not only at their thickest, but nearly perpendicular to the force of rotation. As Sam pointed out, the major cause of bridge lifting (aside from low RH) is, I -believe-, cold creep allowing the bridge to roll forward causing the force to not only be in shear, but in an upward 'peeling' direction.

With all those factors (height, direction. Lam plate/bridge) I would think the falcate to be about as bomb proof as it can get while still making pretty sounds.
Author:  SteveSmith [ Fri Mar 20, 2015 10:04 am ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
Hesh, I used System 3 T88 for my falcate braces.
Author:  John Killin [ Fri Mar 20, 2015 11:21 am ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
Hesh wrote:
Still thinking here how to not have the epoxy glue the clamps since I think that epoxy will attach to waxed paper which is often what's used to shield clamps and magnets from Titebond and HHG. Not sure on this though, epoxy and waxed paper.

To the guys who have built a falcate braced instrument what epoxy did you like?



I'm not sure how well this would work, but in the canoe building world the mold is waxed before the fiberglass or Kevlar is wetted out with epoxy. I haven't tried it (because that is another expensive hobby I haven't been able to justify yet) but I've read where in addition to the wax now people are using the film that you seal your windows with in the winter as a barrier to cover the mold. This leaves a smooth surface on the inside and allows the fiberglass to release from the mold easily.

I bet you could use that film in place of wax paper with some practice.
Author:  John Arnold [ Fri Mar 20, 2015 12:04 pm ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
Quote:
A laminated plate might not and likely will not split but it still can distort I would suspect. If it does it would need to be replaced or this distortion may contribute to another bridge lifting since the under lying support for the bridge is distorted.

You can heat press the bridgeplate in place to flatten the area.
Author:  SteveSmith [ Fri Mar 20, 2015 1:29 pm ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
I used wax paper when I laminated the falcate braces together with epoxy. I can say that MOST of the wax paper came off and what didn't was not a big deal.

Attachment:
FalcateGlueUp.JPG
Author:  david farmer [ Fri Mar 20, 2015 6:24 pm ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
Hesh! Your looking at pictures of Falcate bracing? and asking about Epoxy preferences?
What is the sound of one repairman sliding down the slope to the dark side? wow7-eyes beehive idunno [uncle]
Your post title was just a tease.
Author:  kencierp [ Fri Mar 20, 2015 6:33 pm ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
I use heavy duty plastic packaging tape as a release bearer -- have yet to find anything that sticks to it. CA-- Bondo -- Epoxy -- PVA etc. nothing sticks. Actually been using it for decades -- currently have "Duck" brand in the shop for shipping.
Author:  johnparchem [ Fri Mar 20, 2015 6:37 pm ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
I have mostly used ultra performance paste wax on my molds and cauls while gluing with epoxy I have not had problem with them releasing from the mold. I have also used was paper which mostly comes off. I use System 3 T88 to laminate my braces together and I use West System 105/206 when gluing the braces down or gluing CF on to the braces.

From Ken's suggestion as well I have recently used plastic packing tape for all sorts of gluing operations
Author:  Hesh [ Sat Mar 21, 2015 5:59 am ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
david farmer wrote:
Hesh! Your looking at pictures of Falcate bracing? and asking about Epoxy preferences?
What is the sound of one repairman sliding down the slope to the dark side? wow7-eyes beehive idunno [uncle]
Your post title was just a tease.


:D Yeah, don't tell anyone OK David? :D
Author:  Haans [ Sat Mar 21, 2015 6:26 am ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
Defending Tradition...

Image
Author:  david farmer [ Sat Mar 21, 2015 12:35 pm ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
It's o.k. Hesh, I have sinned in my heart too. ;)
I actually think it's kind of cool that folks around here pack CA's and Rainsongs on long river trips.
Hard to deny the efficiency and practicality. If it gets hot in the sun, finnish cooking lunch on the back and just dip it in the river to cool. loose a paddle? There ya go!
It's almost enough to make me forget a fret dress I did recently.
The neck came out of the factory w/ .015"relife in the neck, a hump over the body and, by god, that's how it's gonna be until the apocalypse, a belt sander on the fret tops, or a come along hooked to the headstock. :D
Author:  Hesh [ Sat Mar 21, 2015 1:51 pm ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
Yeah Rainsongs are impressive no matter how devoted one may be to tradition..... or not.....:) Certainly way better build quality over Ov*tion.... And they can sound pretty impressive too. Reminds me of how I put myself through university being a sailboat dealer in a town with no water.... I remember being in the fiberglass hull commissioning a Catalina 27' and just how good the tunes on the radio sounded in the fiberglass hull.

Funny you should mention the belt sander... I've been tempted.... on some of these really tough fret dresses to employ a hand held belt sander.... and I've even brought it up to Dave Collins thinking that if I give him the idea in a couple months I will have a purpose built electric sander for fret dresses.... :)
Author:  Hesh [ Sat Mar 21, 2015 1:52 pm ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
As always superb work Hans!!! That pic defends tradition quite nicely (if we ignore the CF :)).
Author:  meddlingfool [ Sat Mar 21, 2015 2:17 pm ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
Not that I'd endorse this as a methodology for fret dress, but theoretically with fine enough paper...

This is my fretboard radiusing machine. The platten is concave with a compound radius.
Author:  meddlingfool [ Sat Mar 21, 2015 2:21 pm ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
Image
Author:  Haans [ Sat Mar 21, 2015 3:35 pm ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
BRW, Hesh...Larson laminated braces.
Author:  Jfurry [ Sat Mar 21, 2015 5:29 pm ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
My mentor h as made a couple Larson copies Haans. Love the laminated braces.
Author:  david farmer [ Sat Mar 21, 2015 7:15 pm ]
Post subject:  Re: Defending Tradition, Bridge plates, Braces, Serviceabili
Yikes meddlingfool, making first contact w/ that thing must take some commitment.
You need a foot switch or something.

If Dave's looking for an encore after the run of saddle mills..... Too much heat w/ the belt sander. I'm thinking, long stroke, reciprocating file with a DC motor and a really sensitive variable speed trigger.
The, "De-humperator"? Turns a ski jump into fallaway in 30 seconds or less! . :)
Page 1 of 2 All times are UTC - 5 hours
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/