question about back graduations

[Arnold Schnitzer]

Originally Posted by Ken McKay

Seems like a perfectly good place to put a spring if you are looking to recoup some free green energy. 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]

Originally Posted by Arnold Schnitzer

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..

[Arnold Schnitzer]

Originally Posted by Ken Smith

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]

Originally Posted by Arnold Schnitzer

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

Read this; Posting Pics Tutorial, by Mike Smith.

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

[Eric Rene Roy]

Originally Posted by Arnold Schnitzer

(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/showpo...4&postcount=39

I will say I did try one thing Hans did, but with bad results (I had to replace a customers back). 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.

[Ken Smith]

Originally Posted by Eric Rene Roy

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/showpo...4&postcount=39

I will say I did try one thing Hans did, but with bad results (I had to replace a customers back). 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]

Originally Posted by Eric Rene Roy

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]

Originally Posted by 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.

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? 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.