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So a real question about patent rights and a real time situation is offensive because its your similar product-- but your support of a meaningless, actually non existent situation questioning my integrity is OK --- really, you are so full of it, please you are after all supposed to be professional. Of course my position is defense this is a totally stupid discussion which again has nothing to do with pin-less bridges. By the way I would think that you would have some knowledge of the subject -- like do fasteners add to the strength of the bridge glue joint, there a chance to be constructive.

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Ken Cierp

http://www.kennethmichaelguitars.com/

I was sorry to see this thread head south so soon. I am also interested in ways to securely mount pinless bridges. That the original poster unfortunately mentioned Lowden's name at some point and that he hoped to build a "Lowden" kit lead others to derail the original discussion.
I think most of us have built our guitars on the designs or elements of the designs of instruments we have admired. Some of us directly credit the source ("Martin clone", "Gibson based", etc.) while others make minor changes and claim them to be totally original. Taylors "NT" neck design has some features that were found on J.G.Stauffer's adjustable necks. The previous use of shims has also been mentioned. That Taylor felt the combination of elements was patentable and did so, doesn't change these facts. I'm sure they would defend their patent if they felt someone was "infringing" it with their work.
I know most discussions wander off topic eventually, and will admit that I am as bad as anyone for this. Hopefully it is in a constructive or humorous way (insert goat picture) rather than in an acrimonious and destructive way.

My support of a meaningless, actually non-existent situation?
Questioned your integrity?

Ken, get a grip!

What I said was:

Then you questioned my integrity by bringing up something entirely unrelated. Guitars are guitars. They have a lot of similar looking parts. Similar doesn't equate to patent infringement. You may have missed this, but it was at least four other people, not me, who questioned your integrity about potentially trading off George Lowden's name and reputation.


Yes. Are they necessary? No.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

"...like do fasteners add to the strength of the bridge glue joint, there a chance to be constructive."

"Yes. Are they necessary? No."

Hi Trevor,
I built some travel guitars with pinless bridges. I wanted to keep the bridge fairly traditional looking and relatively light weight. The bridges' held up fine for well over a year when tuned to pitch, but after being put in a sale venue came loose. My assumption is that at some point they were tuned at a higher pitch and that they were too close to the limit of the glue's strength. I repaired them by regluing and using small bolts through the bridge. But I am searching for other methods to improve the holding ability without noticeably increasing the footprint.

Hello Ken,

I believe you did yourself the most harm by deleting your original posts. I would totally accept your explanation and feelings on the matter if you would have been forthright about it last Sunday. Now it's a bit of a gray area for me.

I for one was trying to participate in your pinless bridge query and I apologize if the comments I made after you deleted your posts offended you. Frankly, your attack on Trevor is really out of line, unprofessional and insulting.

Sincerely,

Tim Minkkinen

TimoM...

It's interesting to hear it works without a bridge plate. Fwiw, Lowdens have bridge plates. I personally feel that the purpose of the bridge plate is more than merely protecting the top from the ball ends, but hey, that's me.

I made a Lowden clone once. It died on the table before completion. Something oily in the cedar top prevented it from taking finish, even after I took it to a professional finisher. After much expense and frustration, I took it outside, shot it full of holes, and left it in the back garden to decompose.

About a year later, I had another whack at it. After much trials and tribulations, I finally completed it. It sounded nothing at all like a Lowden and in fact sounded quite bad. So I got in there with the planes and reworked the resonances to my normal numbers and it sounded much better, but still only an 8 outta ten. I played one song with it at an open mic, then left for Scotland with it, where it promptly disappeared at the Paris airport. I took it as a sign that maybe I oughtn't bother trying to clone Lowdens, though the shape will be what I se for my medium jumbo.

Ken,

Many (most) of us base our guitars after makers long dead, whose products are more or less public domain in practice, if not necessarily by law.

Your original deleted post stated that you were going to produce and market a Lowden kit sold by that name, including his proprietary Dolphin bracing, by name. Sure, his 'Dolphin' bracing is just a marketing spin which is pretty much meaningless, but everyone knows exactly who you're talking about when you say it. Since George is a living, working luthier with a family to feed, I think stepping on his toes like that is a little iffy practice, and that is precisely why I have turned down the many requests to replicate his guitars that I have had. If you decided to make and sell a medium jumbo kit with rounded-not-knife-edge bracing it might get more acceptance. Or you might try to contact George to see how he feels. Maybe he'll give you the thumbs up, who knows? Though personally I've tried contacting him with that very request myself a few times and got no answer, and since for me, not a no is not the same as a yes, I didn't proceed with more of them.

Your heated and late responses aren't really making you look good, if you care about that.

I was looking for the RESET button on this thread but I don't see one....

Bob

P.S. I should probably point out that that is my sarcastic humor again....

Oh, and as far as practical attachment goes...

Pinless bridges require fasteners about as much as standard bridge do. In other words they don't. So just design a bridge with enough footprint for the glue to hold and you're good to go. I wouldn't skip the bridge plate though. For the last year or so I've been using bridge plates with a curved back that extends behind the bridge for about 2cm, and have found that is has very much reduced the bellying behind the bridge typical in a Martin/Gibson based design...

This thread is starting to head down the road to distasteful. I'd rather not see another source of knowledge decide that participating in this forum isn't worth the bother.
How about some more discussion that relates to the original topic - I for one am interested.

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

seems like a subject that I would also like to see explored here , especially by the ones who have experience with pinless bridges, I have only owned one pinless guitar , a Breedlove, and it had a mechanical attachment as well as being glued...

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MK5acoustics.com

The original, now deleted question was whether or not a Pinless bridge required additional mechanical attachment (or maybe it was whether it benefitted, I can't recall exactly, and it's gone now).

There seems to be a bit of a debate about whether the mechanics of a Pinless bridge causes more strain on the glue line than a pinned bridge with the ball ends pulling up on the bridge plate. I'm not sure if one side won the arm wrestle conclusively or not.

There are thousands of guitars that have been out there for a long time with Pinless bridges using only glue, so I think it's safe to say that the design, if it has enough square inches of gluing area, does not require additional mechanical fasteners. Just like a normal bridge, all it needs is a good joint and bobs your uncle.

The guitars that I'm aware of that have had additional mechanical fasteners, that have subsequently had glueline failures which caused the bolts to pull up through the top, have been Gibsons. The bolts were small enough that the head would fit into a 1/4 recess, so the shaft and nut were very wee. They had no washer on the inside either, so when it was down to fastener strength alone, the string tension was directed entirely onto two very small surface areas, thus the pulling through the top.

I would think that if decent sized washers were used, mechanical fasteners would be more useful.

But I still don't think they're necessary in either design.

I for one also have an interest in this topic. I had a similar discussion over at the Gibson forum when I was redoing my J-40. That is more or less the J45's little brother and is made from the backs, sides and tops that were not accepted for the 45's. The big difference is it has double X bracing and a pinless bridge. When I redid it I was thinking of putting a pinned bridge on it so I asked at the Gibson forum about the difference in tone. My concern wasn't so much about it being bolted on (which it is) but more about how it effects the tone. The response I got from guys that actually owned the J40 is that they didn't think the tone was effected much by the bridge but more by the double X bracing. I ended up using the original bridge but I shaved and scalloped the braces down and today it is one of my Go-To guitars for having a big sound.

If I were to build one with a pinless bridge again I would probably copy the J45 including the bolts. I am not an expert on the topic but to me it seems you would want the bolts installed. It seems to me that the bolts would do 2 things. 1. because the bridge is now being pulled straight up toward the nut the bolts would help keep the tension off the glue joint. 2. The bolts would act like a fulcrum much like the strings do on a pined bridge putting more tension on the lower bout which would help the lower bout to vibrate more efficiently.

Again, I am no expert by any means but looking at it from a strictly physics point of view it seems logical to me to have bolts. Plus you can then put those cool pearl dots you see on Gibson bridges...

Bob

Bolts or other hardware store variety fasteners are not required to hold a pin less bridge in place. True some manufacturers have used hardware to augment bridge attachment in the past but also as already mentioned in some cases they were used as locators and possibly for clamping action as well (clamping action idea is speculation on my part).

If you Google "pin less bridge" and find the link to the AGF there is a decent conversation there, four pages worth, where Al Carruth brings up the unwanted extra mass of additional hardware and in a very important spot as well, center of the sound board and how undesirable this is or at least is to those of us who pay attention to the various components that make up a guitar top.

Additionally how many tens of thousands of Harmony Sovereigns and the OMish little brother were produced with pin less, not-agumented-by-stinkin-hardware-store-nuts-and-bolts, bridges many of which are still firmly attached to the instrument. Sometimes looking at history can be telling as to the future, sometimes not so much....

Anyway as someone who has removed and reglued way more bridges including pin less bridges that I care to remember on this lazy Sunday afternoon when I have two electrics behind me waiting for attention hardware is not necessary.

What is necessary is good form with bridge attachment, knowing how to use the glue that you intend to use, not using a glue that sucks in sheer, a decent sized foot print for the target bridge, a perfectly prepared bridge patch and bridge underside (don't forget to scrape just prior to glue application) and having a methodology to get all clamps in place if using the recommended HHG prior to the glue jelling is FAR more important. Do all these things well and you too will never need any stinkin bolts.

BTW - when we repair bridges that have been bolted on by the manufacturer it's not unusual for us to fill the hardware holes (two layer, turned on a micro lathe, plugs with each layer matching the top and plate material AND grain orientation as well) thusly, although mouse nuts so-to-speak... increasing gluing area. The original bolts go in a little parts bag in the current steward's (client's) case. Of course the "what's appropriate for the instrument" thinking applies here as well and I am speaking of a player instrument not a historic, museum piece.

Lastly some older Gibsons with that awful plastic bridge although not pin less they did use a lot of hardware to secure them to the top. It's common for these cool old girls to be very valued players these days and on my site is a write-up of how we replaced the plastic-fantastic... bridge with a shop-made wooden bridge - the bolts got pitched.... Replacing the plastic bridges on old Gibsons is also something that we seem to do often and everyone always reports a huge improvement in tone - what ever that means....

Regarding servicing it can be more difficult to remove the saddle with strings in place on certain designs but so long as there are enough windings on the tuner posts and not self-locking modern tuners the saddle can still be removed and I usually only remove the low e, a, and d to get to it. I also remove the saddle before a restring and inspect and tweak the fit as need be so that I don't have to do any unnatural acts to get the saddle out once stings are on. Everything that one does in setting up an instrument can work either for you or against you depending on the order of the process. I greatly prefer to have it all work for me and love it when it all does.

So are bolts required - no, are they a good idea - no, is there a down side to bolts - yes, added mass in a critical location, can a pin less bridge stay in place without bolts - yes.

How big does the footprint of a pinless bridge need to be to keep it in place when tuned up a step and a half above standard (EADGBE) pitch?

Might be time to do some testing and find out? It's not all foot print either other contributors to a success or failure include glue, woods, prep, top bracing avoiding distortion, RH, bridge design, neck angle (torque on saddle....) and perhaps some luck too.

Of the few pinless bridges that I did see that failed, the weak link was the bridge area. Yes the glue joint of the pinless bridge will be stressed higher than a pinned bridge. That failures I saw was caused by no plate , this allowed the bridge to separate. The tops also showed sever rotational stress. One used a bolt and after the glued joint failed the heads of the bolts came through the top.
Of the ones I have seen without any issue they had plates. Bridges had about the same foot prints of a typical belly bridge.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Hi Meddling,

Well for me, as I explained, it started as an experiment. I saw no reason for a bridge plate on a pinless bridge and stand by that assertion. I used a relatively stiff top, left it a bit thicker than normal, 105% of my typical target deflection, a 95 degree X brace, 5/8'' tall a the X. The bracing is tapered, no scalloping. I have a few mule tops that I do tests on, if the bridge is securely glued and the bottom of the wings cover the X it takes far more force than 140 ft lbs of torque to rotate an unplated bridge more than 1.5 degrees. Now if you scallop the X and use an over thinned top and add a deep bridge plate it is a different story, you create the scenario where failure is inevitable, you are enhancing rotation, pinless or not.

Of course I have no way of knowing that this pinless bridge guitar will last for decades, but in my experience structural failures start to reveal themselves relatively quickly. The photographed guitar that we are talking about is nearly 3 1/2 years old and the top shows only very slight distortion. The tweaks I recently made were redoing the nut and saddle to the standard I now hold after 15 more scratch guitars, releveling the fretboard for the same reasons and drop filling areas that I originally didn't really care about as it was an experimental.

As for the tone, one of the primary remarks is it sounds "clean", overtones are few. It has remarkable clarity, quickness and tonal separation and was very inspirational to me as a builder because it revealed a tonal nature achievable within a guitar I was unfamiliar with. The sound is not for everyone and its not "loud" but it is balanced. "It's the type of guitar many good players would like at their disposal", is also a common remark. Thanks for the interest.

Tim

Oh boy
Yes you need something there. If you don't have structure to support the torque and stress on the top from the bridge , it will fail.. What is the bracing you plan for under the bridge ? The top will not be stiff enough. The plate is not there just to hold the pins , The bridge , top and plate work together. On a pinless you have to support this area . Would like to see what you have planned.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

John,

The guitar is built and functioning fine and has been for over three years. What I have planned is to do more of them in the future. A bit off base to not read the post you are commenting on. I hope there's alcohol involved.

Tim

It's hard to say exactly what might have happened there, Clay, but tuning up wouldn't be my first thought.

I've gone to quite a bit of trouble on my designs to use pinned bridges, threading braces between pin holes etc., even on dense lattice designs. One significant reason for this is just the personal usability aspect - it is just so much easier to bang on a capo, drop the string tension and pull the pins if you want to do any adjustments in that area.

If you look at the pinless designs that survive, the Ovations generally do and have very stiff tops, so deflection is not a problem. I haven't had a close look at Lowdens to see how George does it, but I suspect it's to do with tapered rather than scalloped braces and including a bridge plate, so keeping the top distortion under control that way.

To me, the failure mode is more likely a peel failure due to top distortion rather than a shear failure of the glue. After all, the footprint of George's bridges looks smaller than a typical Martin belly bridge. And I suspect that is why yours failed in the sales venue, just a build up of top distortion (creep) over time leading to a peel failure. Cycling of temperature and humidity would accelerate that, so may have been a factor if that was happening too.



I've come across a cedar top like that, Ed! I had three goes at French polishing it and the finish just balled up, not wetting the surface. Usually, cedar is real easy to FP. I ended up shooting that guitar, but with nitro. Worked fine.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

The structure may be sound. 3 yrs is a good test and forgive me for speeding past that post. Having captured the bridge at the X will help and I hope you see stability in the future. I have read your post and will say that your design may be sound. Of the failures I have seen they were on spruce . The braces also were not under the bridge but did hit the front corner.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Trevor , seems like some slight modifications to your falcate bracing my be the ticket to controlling top distortion for a pinless bridge???
I would be interested in what you think, sounds like something I mike like to try..

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MK5acoustics.com

Well, there's CF in the bridge, bridge plate and bracing on the standard design, and the tops don't seem to creep, so it may well take a pinless bridge without any mods. I've never tried it, as I prefer the usability of pinned bridges, so I can't give you a definitive answer. By now, someone has likely given it a shot.

Didn't Taylor use pinless bridges at one time? And then changed back to pinned. Anyone know why? Appearance? Usability? Structure? Economics? Other?

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

After a rough start, this thread has become an interesting subject that kinda makes you go Hmmmmmm...anyone got any pics or drawings to share with ideas, or stuff that didn't work?? Maybe come up with a OLF inspired and designed pinless bridge system, kinda like the OLF guitar plans from year back??
Just thinking and having a glass of wine watching the Spurs take to the Heat!!

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MK5acoustics.com

Trevor,

You're good at math and stuff. Can you tell us if a pinless bridge actually puts more stress on the glue line than a pinned bridge of equal footprint?