question about back graduations

[Rob Menapace]

I have a roundback bass that's had a top off re-graduation plus a new bass bar, the back also was re-graduated, but with the back still on. So the back is still the original thickness around the edges, where it connects to the ribs. How important is it that the back have it's graduations going all the way to the edges? I'm trying to figure out whether it's worth the extra expense to have the work done. The bass is sort of a pet project of mine, I've probably already exceeded the amount that it's actually worth, but I've gone this far, and I'm hearing conflicting ideas about how important the back is. There's the idea of "if it ain't broke, don't fix it", but I also know that the edges can be especially critical in the graduations. I'm just hoping for some general info on the importance of the back graduations from some of the esteemed experts that post here, thank you!

[Ken Smith]

Well, just for conversation, what were the thicknesses of the Back measuring in the center on thru to the edges by the Lining and what are the numbers 'after' you re-graduated the Back? Also, what were the numbers of the Top as well?

In my opinion, numbers by themselves do not tell the whole story. The density of the wood plays a huge role as do the dimensions of the bass as far as the length and width of the plates and combined.

Harder wood can possibly go thinner than softer variations of the various species. Wider and/or longer pieces might need to be thicker than smaller ones like the difference between a Cello and a Bass but in a gradual sense. Arching and Bracing also add to the equation or subtract from it at times. A bigger arched Top by design is stronger but not necessarily better.

I have one English Bass with a very dense Top that someone thought from looking from the F cuts was too thin and his comment to a potential buyer helped to 'kill' a sale for me. When it was later 'gauged' and its extra density evaluated it was deemed 'graduated just right within itself'. 'Within itself' is the key phrase here. If the wood is soft and you go too thin, it will be weak and fail in one or more ways. If the wood is hard and left too thick, the sound will be suppressed to the degree that the plates are not graduated within its personal range.

How do I know all of this? I don't, and I admit it. I just happen to have owned many many basses or all ages and schools of making and have had most of them on a bench at one time or another for examination as well as seeing many other basses that I didn't own. After examining more basses than I can remember, I do know that more often than not, the bass is too thick or too thin somewhere on the plates. If we are not sure by just looking at the Bass, then the graduations are left alone. Only when we are totally certain that something is way off to I approve an action in regards to graduation or adding back in. 'We' meaning the Luthier and myself discussing the work to be done.

What to do? Evaluate every project thoroughly before cutting anything. Taking away is easy. Putting back is not. Adding breast patches to re-thicken and reinforce a thinned, depressed or sunken Top is very difficult and not all the Luthiers do such a great job of it. Many basses done in 'professional' shops have been repaired for profit rather then for quality and 5, 10 or 20 years down the road the truth will be told when the Bass itself speaks out from its human imposed illness!

[Ken McKay]

Back grads are critical, edges are not. Where the plate is glued to the ribs/linings, thickness and stiffness are not important within normal limits. It would waste your money to regraduate the back plate again for that reason.

As a matter of fact I think the best possible way to graduate the back would be from the outside after the instrument is fully strung. But that has nothing to do with your question.

What exactly are you thinking you might want to achieve by this regrad?

Someone with a few basses could try this experiment of give and take. Tap the back at the point where the SP is situated with a thump of the finger. Listen for the sound level of the open strings. Now repeat with a couple other basses and relate this to their sound level, loudness, punchiness (not necessarily timbre) . A stiff back can prevent a bass with a perfectly good top from sounding loud and responding to the bow well. Now reverse this in your head as you imagine the sound starting at the string, through the bridge, rocking the top, causing the post to move the back.

[Rob Menapace]

Thank you for the helpful replies. What I am trying to achieve is a bass that's been properly re-graduated, given the general standards of acceptance. I had to ship the bass to have the top work done, so I'd like to make sure the bass is correct before it gets shipped back. I was not sure how important the edges of the back plate were, if I understand the above reply, they are not as important as the overall graduation of the back plate. The luthier feels the benefit of taking off the back and redoing the edges might be marginal. I mostly wanted to make sure that the work done is correct, for both achieving it's full potential tonally, and also for when the time comes that I might have to sell it. Thanks for the info on the tapping experiment too, have to try it. I'll work on getting the numbers on thicknesses.

[Arnold Schnitzer]

Both Kens gave excellent information above. To stir the pot a little: there are makers who believe that the back table should be as stiff as possible and not vibrate, therefore allowing the top to vibrate more. Then there are makers who believe the back should behave as a secondary soundboard and vibrate like crazy. Whether you rework a back table's thickness (and by how much) will depend on which camp you are in. I've seen back thicknesses (round-backs) of 6mm all the way to 14mm.

[Ken Smith]

Both Kens gave excellent information above. To stir the pot a little: there are makers who believe that the back table should be as stiff as possible and not vibrate, therefore allowing the top to vibrate more. Then there are makers who believe the back should behave as a secondary soundboard and vibrate like crazy. Whether you rework a back table's thickness (and by how much) will depend on which camp you are in. I've seen back thicknesses (round-backs) of 6mm all the way to 14mm.

14mm? Did we both see that Bass?

Anyway.. Of the Basses I have owned, those with harder maple backs seem to project more volume providing they were properly thicknessed within. Those with softer backs seem to put out a softer tone, less penetrating in the mids. The only softer maple Backs I have seen recently are those of Italian Oppio, a local wood of north Italy used often on Italian basses and Cellos. I currently have two Oppio Backed basses and although both loud and deep, they do not 'throw' out the sound as well as some other basses with harder maple regarsdless of them being round or flatback.

[Arnold Schnitzer]

Ken, I hope you are not comparing flat-backs to round-backs, because the bracing on flat-backs makes them a whole different animal. I assume the O.P. was discussing rounds. Am I mistaken? My experience as a maker tells me that harder wood on the back and sides usually relates to a brighter sound, softer wood to a more mellow sound. I don't notice a difference in projection.

[Ken Smith]

Ken, I hope you are not comparing flat-backs to round-backs, because the bracing on flat-backs makes them a whole different animal. I assume the O.P. was discussing rounds. Am I mistaken? My experience as a maker tells me that harder wood on the back and sides usually relates to a brighter sound, softer wood to a more mellow sound. I don't notice a difference in projection.

Yes Arnold, Round Back on the Graduation think but again, some basses even with Flatbacks that seem to heavy feel like the sound is held back. Some Roundbacks with softer wood seem deeper and more of a spread sound then the harder Backs that have more punch or long range penetration.

There are so many variables here so I will step aside here as this is just my experience from the basses I mainly use and have owned. That's a lot of basses actually in comparison but still, it's something I've noticed.

[Ken McKay]

... there are makers who believe that the back table should be as stiff as possible and not vibrate, therefore allowing the top to vibrate more. Then there are makers who believe the back should behave as a secondary soundboard and vibrate like crazy. Whether you rework a back table's thickness (and by how much) will depend on which camp you are in. I've seen back thicknesses (round-backs) of 6mm all the way to 14mm.

Interesting comment. Put me in the back-needs-to-vibrate camp.

As far as back plate stiffness goes my understanding and belief is that the top and back plate should match in stiffness somewhat. A double bass resonates similar to big violin when it has a carved back plate. Customarily the plates are usually tap-tuned so that they are about a tone or semi-tone apart or thereabout. This seems to be traditional and results in a normal sounding and responding instrument (violin, viola or cello and roundback basses).

If the instrument sounds stiff and non-resonant it might be a candidate for a regrad. After measuring the thickness of the top, if excessively thick, I might consider taking it off for some thinning. Any structural concern would trump any thinning for resonant purposes.

While the top is off, I would assess the top and back thickness and get the frequencies of their modes, Taking into consideration the type of wood but regardless, I might try to match the back to the top by thinning one or both while the top is off. One tone to a semitone is what I would shoot for depending on where they are to begin with. There would no advantage to removing the back for this. The tap tone of the back on the ribs will be close enough.

If it were a flat back bass, the individual braces might be too thick or thin and can be thinned or rebraced to achieve a normal stiffness. there is no tap tone of a flat back, it acts more like individual sections with their own resonances in each section. The platform that the soundpost sits on I think of as a separate resonating body. But it shouldn't be too floppy or stiff. I have no tuning scheme for the back braces but here is my belief. Flatter, thinner back braces act more like a carved back, smoothing out the resonances with higher damping to spread the peaks of the individual resonances of the braces tones therby making it more like a carved back which has a more damped tones. Flat backs are peaky with closely spaced resonances, while carved backs have less peaks but are much wider with higher damping. They vibrate in a different ways, if you have lazor and a camera you can see it clearly, or better yet, just read about it.

[Arnold Schnitzer]

Ken M., it's my belief that when backs and tops are "voiced" too closely to a pitch, the result can be a wicked wolf tone. Also, I think most flat backs are way over-braced.

[Ken McKay]

Some interesting inside baseball for ya...

On my cornerless bass that I just finished I made the top first and then wanted a hybrid bracing for the flat back. I designed my own to spread out the stiffness with an X-brace with the intersection at the soundpost. This is not anything new, many makers have done an X but mine was different because it is braced similar to a flat top guitar that CF Martin designed. An X with lower fan type braces. The reason was for the braces to hold the back into a slight dome shape with minimal weight. I thought this might make it behave similar to a carved back. And not have the cross grain situation of the flat back with its cracking problems.

Since I was shooting in the dark I tap tuned it, removing wood from the braces to make its stiffness similar to the top. The X back did have nice ringing tap tone that was close to the top's. It was about a tone higher. After stringing, it did have a pretty strong wolf at open A. I was kind of expecting that and was able to move it a little as to not interfere with bowing by using a brass weight on the afterlength.

The bass seems to have a pretty nice smooth round sound that is a little different from the typical flat back to my ear. As for long term stability, I am certain that I have done a positive thing by not gluing 3 or 4 braces straight across the full 27 inch width of the back. So now the wood can expand and contract across the grain freely as well as flatten the dome when it gets dry. I will know if a few seasons just how beneficial this was but have already noticed the back going flat during dry spells. I also notice the post getting looser and tighter with this.

[Ken Smith]

Some interesting inside baseball for ya...

On my cornerless bass that I just finished I made the top first and then wanted a hybrid bracing for the flat back. I designed my own to spread out the stiffness with an X-brace with the intersection at the soundpost. This is not anything new, many makers have done an X but mine was different because it is braced similar to a flat top guitar that CF Martin designed. An X with lower fan type braces. The reason was for the braces to hold the back into a slight dome shape with minimal weight. I thought this might make it behave similar to a carved back. And not have the cross grain situation of the flat back with its cracking problems.

Since I was shooting in the dark I tap tuned it, removing wood from the braces to make its stiffness similar to the top. The X back did have nice ringing tap tone that was close to the top's. It was about a tone higher. After stringing, it did have a pretty strong wolf at open A. I was kind of expecting that and was able to move it a little as to not interfere with bowing by using a brass weight on the afterlength.

The bass seems to have a pretty nice smooth round sound that is a little different from the typical flat back to my ear. As for long term stability, I am certain that I have done a positive thing by not gluing 3 or 4 braces straight across the full 27 inch width of the back. So now the wood can expand and contract across the grain freely as well as flatten the dome when it gets dry. I will know if a few seasons just how beneficial this was but have already noticed the back going flat during dry spells. I also notice the post getting looser and tighter with this.

Ken, unless you make two identical basses it's hard to attribute the sound to the bracing. The Cornerless design in itself is a huge difference in sound due to the fact the fibers run end to end with no blocks stiffening them up in the middle. I think you have too many variables here to consider the bracing itself a contributing factor.

[Ken McKay]

Well, I kinda agree with you there Ken. But a flat back is a viol and a roundback is violin. Each type has a characteristic timbre regardless of the shape of the instrument. Psychoacoustics and playing style also have an effect on the sound of a given instrument but the mental exercises transfer to reality. For example ask yourself what if this bass had that back or what if this roundback bass had a flat back? Armed with all of the available knowledge we have, as well as tradition and a good ear, the puzzle comes together.

In other words expected results are born from understanding.

Attached is Andrew Brown's double bass dissertation in pdf.

[Ken Smith]

Well, I kinda agree with you there Ken. But a flat back is a viol and a roundback is violin. Each type has a characteristic timbre regardless of the shape of the instrument. Psychoacoustics and playing style also have an effect on the sound of a given instrument but the mental exercises transfer to reality. For example ask yourself what if this bass had that back or what if this roundback bass had a flat back? Armed with all of the available knowledge we have, as well as tradition and a good ear, the puzzle comes together.

In other words expected results are born from understanding.

Attached is William Browns double bass dissertation in pdf.

Ok, you expect me or someone to read this 136 page study and make something out of it? From this study, what advancement on the making or repairing the DB has come about?

I think the Wood and The Varnish has a lot to do with the sound of a bass as well. The Player not so much. Maybe a good player can get a better sound than the Plummer can but even if my wife pulls the stings on my Storioni it will sound like the Storioni.

[Ken McKay]

Oh common! A little light reading...Paul reads it in the bathroom.

Truthfully, I don't expect anyone to read it or be interested in this unless they are a geek like me. But there is a lot of good stuff in there with some very careful and thorough research and investigation. I see you read some of it by your comments...:D

There is a lot of stuff to talk about if anyone is interested. This might be a good topic of its own.

[Ken Smith]

Oh common! A little light reading...Paul reads it in the bathroom.

Truthfully, I don't expect anyone to read it or be interested in this unless they are a geek like me. But there is a lot of good stuff in there with some very careful and thorough research and investigation. I see you read some of it by your comments...:D

There is a lot of stuff to talk about if anyone is interested. This might be a good topic of its own.

I posted 13 minutes after you. Giving the time to post and the time I wasn't on line a few minutes and the time scrolling thru that link after I opened it only to find there were 136 pages... I may have read a sentence or two.. not three.. I looked at a few pictures as well.. lol

No, anything I said or posted had nothing to do with that link or study other than mentioning it was 136 pages long. That much I noticed.

I have a few basses in restoration right now that will need wood added back into the top to fix the Butchery that went on in it past from other luthiers. I say this now.. It it sounds good, leave it alone unless you know fairly sure that it still has a ways to go and also do so without weakening the plates.

With basses being so different from one another in every which way, unless you are using some controlled materials, that study does very little to contribute to the improvement of the making or repairing of a double bass.

[Rob Menapace]

This has turned into a pretty good thread! I just wanted to clarify...if anybody is still following from the original post, that the bass in question is just a shop bass with interesting wood and a comfortable size/shape for me to play. I would certainly never re-graduate a real makers bass. When I bought the bass, it had had a bunch of work done to it, including the re-graduation of the back (with back on), and re-graduation of top, graduated around the bass bar, and not all the way through to the edges. The current work being done is to graduate the whole top and fit a new bass bar. I've decided to leave the back alone, partially based on some of your responses, mostly based on the suggestion of the luthier doing the work...just wanted to say thanks for opinions/info, also I did read some of the 136 page paper, I'm into it, thanks for posting the link.

[Ken Smith]

This has turned into a pretty good thread! I just wanted to clarify...if anybody is still following from the original post, that the bass in question is just a shop bass with interesting wood and a comfortable size/shape for me to play. I would certainly never re-graduate a real makers bass. When I bought the bass, it had had a bunch of work done to it, including the re-graduation of the back (with back on), and re-graduation of top, graduated around the bass bar, and not all the way through to the edges. The current work being done is to graduate the whole top and fit a new bass bar. I've decided to leave the back alone, partially based on some of your responses, mostly based on the suggestion of the luthier doing the work...just wanted to say thanks for opinions/info, also I did read some of the 136 page paper, I'm into it, thanks for posting the link.

I have heard of some fairly high end basses being re-graduated to correct what they though was made wrong. I have heard that many Strads and the like have also been altered internally to make them perform up to current standards. This is not always successful.

Like I mentioned, I have had basses go both ways in restoration, wood in and wood out. So far, every bass was improved.

On your bass that was worked around the bassbar, let me give you some information that might help. 30 or so years ago I heard about a full sized Maggini in a big shop for restoration. Along the entire bassbar area the top was built up under the bar. The Luthier thought that this famous maker was wrong and he was more knowledgeable. He removed the excess wood under the bar and 'sprung in' a new bar and closed up the bass when all the work was done. Guess what? The Top collapsed!.. This Luthier thought he knew more than Maggini.. Go figure..

When my Gilkes (Jilkes) was opened up for restoration and a new bassbar, I felt along the Bar area inside the Top and guess what? A similar platform as was described to me that was in the Maggini. That Bar platform-Top relationship was left intact and the Bar place in the Bass without any spring at all. This Bass dated 1814 on the Label has never cracked and has never sounded better in the 5 years I've had it.

Maybe in your Bass, leave a platform built up under the Bar like Maggini and Gilkes did. I would try that if it were my bass if possible just to see what it does.

[Arnold Schnitzer]

I read some of the dissertation Ken M linked. What I found most interesting was the response of players to the round vs. flat back comparison. Comments were all over the place and contradictory. The author pointed out how subjective the whole subject is. I personally think there is something to having a "spring" of brace wood under the soundpost, regardless of whether the bass has a round or flat back. I have had the opportunity to add a back brace to a round backed bass on several occasions, and felt the bass responded quicker afterward. Ken S. has some experience with this as well. Your comments, Maestro?

[Ken Smith]

I read some of the dissertation Ken M linked. What I found most interesting was the response of players to the round vs. flat back comparison. Comments were all over the place and contradictory. The author pointed out how subjective the whole subject is. I personally think there is something to having a "spring" of brace wood under the soundpost, regardless of whether the bass has a round or flat back. I have had the opportunity to add a back brace to a round backed bass on several occasions, and felt the bass responded quicker afterward. Ken S. has some experience with this as well. Your comments, Maestro?

Well, let me start by saying if not for seeing this already in one old Italian that passed thru my hands as well as seeing it in use on New basses made by both Arnold and Jeff B. I would not have felt as confident as I did when I requested such a modification on two of my own favorite Italians.

My Candi went in for some repairs and a new Neck Graft. Due to an old repaired crack in the Back running up from the bottom to the soundpost area I suggested we put a center brace in the roundback Candi for two reasons. One, this would keep direct pressure off of the Crack from the soundpost for ever! and Two, the Candi made from soft Italian maple aka Oppio would benefit as well from this structurally and hopefully tonally.

My Martini has a 3-pc back of this same Oppio but seems to have been graduated much thicker by the maker back in 1918/19 when it was made. The soundpost had over the years pushed on the back joint that is only a few inches from the post but outside towards the C-bout, not a center joint as it is 3 pieces as I mentioned. This center brace was more of an alongated back patch but a brace no doubt joining the center and outer pieces of the back therefore once again taking the direct pressure off of that joint nearest the Post area. The Candi brace was mostly all across but did not reach all the way t the Ribs or linings. Thus a center brace/patch in one.

Results?. Both basses are louder, more focused sounding and healthier as well. I was very pleased with the outcome as I know both of these basses from before the repair.

At the ISB this summer with all of the great old and expensive basses there the Candi had quite the audience. Italian Luthier Sergio Scaramelli came by several times during the week looking it over and playing it with passion I might add. A true compliment to the bass. Sregio mentioned he owned a Candi Cello that in other words, needed his big brother back home if you get my meaning. At this same time, world renown Italian bassist/soloist Stefano Sciascia played the bass and I must tell you, this guy can make a grown man cry. He was there to play in one of the venues in which the Karr/Koussevitzky bass had been prepared for him to do so. He told me if not for the Karr bass (the one they 'used' to call an Amati) he would have chosen the Candi to play. I played the Karr bass and I must say, Sergio would have sounded much better with the Candi. It has more power and more color to the sound. If just doesn't have the Karr mojo in it. Maybe I can call Gary and have him play a few minuted on the bass and see what mojo might rub off.. You think?;)

There is something to be said for adding this center Brace in many cases. My Gilkes however is made from such dense wood that it was not even considered. The Gilkes is a bass made from the finest woods one could ever wish for, made by a maker with magic in his fingers and posses more power than any 3/4 bass I have ever seen matching and surpassing most 7/8ths and 4/4 basses I have seen in projection as well. This Bass needs only to be played as it was made as perfect as a Strad Cello and needs no modifications.

Modifications are good to do if it helps the bass. If it ain't broke, don't fix it!

[Ken McKay]

Well, since the meastro spoke, I might take a turn.

Regarding the players responses to the listening test being contradictory and variable. Browns summary on the subject:


It can be seen that the opinions of bassists on the subject a spectrum of bassists contains bassists that believe the difference is clear and important and others who believe there is no significant difference. Many of the responding bassists are somewhere in between, unsure if a real difference in sound between the two types exists.
And then Brown goes on to show that there is an acoustic difference and measures it and publishes it. Interesting that players have variable views but it makes perfect sense since both types are seen in modern orchestras almost interchangably.

Martin Schleske a modern violinmaker who is alive today makes "tonal copies" of some of the finest stradivari and del Gesu violins. He charges a small percentage of what it would cost for an original. As a physicist and violinmaker he has developed some techniques to test and replicate violins. Schleske was quoted by Brown in the dissertation on page 47 to say:


"To make an acoustal copy of a Guadagnini bass, it would cost almost as much as the original instrument. The ratio between the cost of an original violin (DM 1,000,000) and an acoustal copy (DM 40,000) is much more attractive than as with a bass (DM 150,000 and DM 75,000)"
And an interesting comment on page 48 (with and illustration by J Bollbach) regarding the static pressures on the bass.


"The back plate of the double bass is subjected to strong forces. The back serves as the anchor for upper and lower blocks, as a platform for the ribs, and supports downward string pressure on the top plate through the soundpost. Each of these areas must be strong enough to support the static forces as well as dynamic forces during playing and transport. About 2/3rds of the downwardstring pressure is supported by the soundpost, whichmay be calculated to about 353 N. (79 lbs) According to Guth."
Seems like a perfectly good place to put a spring if you are looking to recoup some free green energy. :cool: And here is also where the graduated plate, thick in the center and thin at the recurve, works to a similar advantage. Or a sprung X brace.

[Arnold Schnitzer]

Seems like a perfectly good place to put a spring if you are looking to recoup some free green energy. :cool: And here is also where the graduated plate, thick in the center and thin at the recurve, works to a similar advantage. Or a sprung X brace. Good stuff, Ken. But why put spring in any brace? To me, that's just asking for future trouble. The cross or x-brace is under spring pressure from the soundpost, so why also stress the glue joint?

While on the subject of bass back bracing, some colleagues of mine suggested installing what amounts to a single angled long brace, which I have used with excellent results. It's up to our esteemed host whether he wants to post the pics. (Nick Lloyd used this same system in his 2009 Silver Medal ISB bass.) It provides the requisite support for the soundpost, but avoids the cross-grain attachment which makes traditionally-braced flat-backs so trouble-prone.

[Ken Smith]

Good stuff, Ken. But why put spring in any brace? To me, that's just asking for future trouble. The cross or x-brace is under spring pressure from the soundpost, so why also stress the glue joint?

While on the subject of bass back bracing, some colleagues of mine suggested installing what amounts to a single angled long brace, which I have used with excellent results. It's up to our esteemed host whether he wants to post the pics. (Nick Lloyd used this same system in his 2009 Silver Medal ISB bass.) It provides the requisite support for the bassbar, but avoids the cross-grain attachment which makes traditionally-braced flat-backs so trouble-prone.

Arnold, do I have pics from the inside of the Bass? If I do which were sent from you then it would be best that you post them. I do currently have the Bass that has that new system and will welcome it in any other future repair as it's seen fit to do so. The Bass sounds at least as good after as it did before. This is the modern English made Lott copy I currently have made in part by the former owned of the actual Lott who is a Luthier and another older Luthier that did the main 'frame work' on the Bass. After settling in the US/NE its first winter, I gave the bass to our esteemed maestro 'Sir Arnold' to repair and he did quite the fine job as usual I must say..:cool:

[Eric Rene Roy]

(Nick Lloyd used this same system in his 2009 Silver Medal ISB bass.) It provides the requisite support for the soundpost, but avoids the cross-grain attachment which makes traditionally-braced flat-backs so trouble-prone.awww...I missed looking inside his bass...I would have liked to see that.

This was some minor inspiration for some that I have been trying...and just good work to look at. http://www.talkbass.com/forum/showpost.php?p=2746464&postcount=39

I will say I did try one thing Hans did, but with bad results (I had to replace a customers back:eek:). He said he did spots of glue every inch or so to allow for wood movement. I did this...and the wood moved...causing a bulge in between two of the glue spots. I won't try that again.

[Arnold Schnitzer]

Arnold, do I have pics from the inside of the Bass? If I do which were sent from you then it would be best that you post them. Sorry, posting pics is beyond my computer capability...

[Ken Smith]

Sorry, posting pics is beyond my computer capability...

Read this; Posting Pics Tutorial, by Mike Smith. (http://www.smithbassforums.com/showthread.php?t=100)

Or, email them to someone that knows how to post them. That someone NOT being me.. lol..:eek:

[Ken Smith]

awww...I missed looking inside his bass...I would have liked to see that.

This was some minor inspiration for some that I have been trying...and just good work to look at. http://www.talkbass.com/forum/showpost.php?p=2746464&postcount=39

I will say I did try one thing Hans did, but with bad results (I had to replace a customers back:eek:). He said he did spots of glue every inch or so to allow for wood movement. I did this...and the wood moved...causing a bulge in between two of the glue spots. I won't try that again.

Are you totally sure it was the Bracing and not the aging of the wood? Besides commercial drying if done so, how long did the back wood sit in block form and/or at near finished dimension before it was used to make a back and put on the bass? How long id it take for the Back to fail.

And, what do you mean by Spots of Glue? Just Glue over the wood or with patches or braces? Ever seen the upper back bend of a Panormo School Bass?

[Eric Rene Roy]

The wood was plenty dry and about 8 years old. The bass was made in the fall of 08...did well through the winter, and then I saw it at the ISB (June 09) and it was fine...perfect even...I looked it over well as it is the one and only I did with glue spots. We had a record breaking amount of rain in June and July...and it was July when it failed. I suspect the owner let it sit in his house with the windows all open and 80 to 90% humidity instead of running his air conditioner to keep it at a more healthy 40 to 50%. Regardless of his care...it wouldn't have developed the problem it did had I glued the braces normally.

By glue spots...I mean take your brace (This bass had traditional horizontal bracing) and put a one inch drop of glue every 2 inches across the brace. This is a bad idea and one I will not do again.

[Ken Smith]

By glue spots...I mean take your brace (This bass had traditional horizontal bracing) and put a one inch drop of glue every 2 inches across the brace. This is a bad idea and one I will not do again.

I have never in my life heard or that or saw that in any bass. What was the 'supposed' purpose of this idea? Glue 'outside' the joint 'on top' of the wood that's glued to the bass?

I have seen plenty of natural glue drips inside of a bass that was just sloppy work but I am sure none of it was done intentionally. My Gilkes had just about the entire Back covered in drips from seams being sloppily glued. Arnold made mention that he scraped off about 2 lbs. of glue from the back during the restoration. I am sure it was more like ounces than pounds but either way, the glue was not there to serve any purpose at all.

I have one old Italian bass in restoration with the upper and lower braces beautifully scalloped. They are slightly wider than normal but fairly shallow with a slight 'roller coaster' design from end to end. I asked the Luthier working on this particular bass (Nick Lloyd) to leave the original 'bars in place if at all possible. This way I could see if the bass sounds good with them in because we could always replace them later if 'bars are not destroyed blindly just for tradition sake.

Glue Drips? Maybe it's some sore of low cost 'sealer' to the wood that a Luthier/Witch Doctor came up with. Leave windows open in the Summer with the Rain and high humidity? Why would any human punish themselves like that and try breathing that heavy wet air. I would suspect he was at least as sick as the bass by that time.. right?

[Ken McKay]

Haven't you ever watched the New Yankee Workshop Ken?

Naam is always gluing things that way! " ...I only apply glue to the center of the breadboard ends to allow for expansion and contraction of the tabletop." If you don't believe me, a video is available which includes a measured draring.

Eric was just applying this concept a little differently, by applying spots of glue to the brace so the back (underneath the brace) could expand in between those spots. There is no glue drips outside the braces. Now he is admitting it is not advisable.

[Ken Smith]

Haven't you ever watched the New Yankee Workshop Ken?

Naam is always gluing things that way! " ...I only apply glue to the center of the breadboard ends to allow for expansion and contraction of the tabletop." If you don't believe me, a video is available which includes a measured draring.

Eric was just applying this concept a little differently, by applying spots of glue to the brace so the back (underneath the brace) could expand in between those spots. There is no glue drips outside the braces. Now he is admitting it is not advisable.

The joint itself was glued in alternate intervals? Well, don't you think you would get buzzes with unglued pieces touching with the slightest movement?

Yankee workshop?:eek::eek: I hope NONE of the Luthiers working on my basses watch shows like that for advice on how to restore an Italian Bass or even a Yankee bass for that matter. Chairs and Tables do not get played. They do not travel around to gigs in varied climates.

If you have to watch the Yankee Workshop to know how to fix something on a professional level then maybe that person needs to apprentice somewhere a little while longer.

[Eric Rene Roy]

Ken, your one of a kind. Uncle.

[Arnold Schnitzer]

Jeez Ken, be nice to your guests or you will not get dessert. :D

[Ken Smith]

Jeez Ken, be nice to your guests or you will not get dessert. :D

Yo, Mr. NY Yankee.., You talkin' ta me??:mad: .. Yeah, like I really need dessert.. wise guy..:p

:D

My comments were not directed at anyone specific. Just in general. If they apply to you and you feel guilty, try the Bull Pit for some Therapy..;)

Tell Richard I sent you. He can put out any size fire I am sure..:)

Arnold, I thought you were on my team!.. "Don't ever speak against the family again"..(Pachino)

If you are running low on Glue, let me know. I hate when things drip..:o

[Ken McKay]

That's it, I'm boycotting this site!:mad:

[Ken McKay]

...for 15 minutes... I'm back. :D

[Ken Smith]

...for 15 minutes... I'm back. :D

How was your vacation.. lol