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Old 03-10-2011, 06:01 AM
Dave Whitla Dave Whitla is offline
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Default Restoration of French bass

Hello everyone. I have a question on behalf of myself and my luthier!
My old French bass is currently undergoing a fairly significant restoration of the top. I’ll attach a ‘before’ photo. It has been re-arched in a cast, and a large number of old cracks, cleats, patches and straps are being removed and redone, including chest and soundpost. The bass bar, which had been sprung too hard and was actually cracking the top from the inside, will be replaced (and not sprung). There was a lot of woodworm damage, around the lower end of the center seam and bass bar particularly, which had been “repaired” using epoxy . This is being removed and new wood patches inserted. The restoration is being done by Tom Barrett and I feel that he is doing an excellent job.

Most of this work is nearing completion (second photo), which leads me to my question. There will be three larger patches covering the width of the upper, middle and lower areas. Obviously this will make the top thicker. What Tom and I are looking for input on is how should he approach the graduation of the top once the overall work is done. I don’t have all the measurements from before the work was started, but the top was quite thin in many places. The center of the top was about 10mm. The bass was cut down at the upper shoulders at some stage, so aiming completely for the original graduations is probably not the way to go, even if we knew them. We have decided to realign the bass bar slightly from its original position to accommodate the ‘new’ dimension of the top.

I would like to keep the beautiful, dark sound this bass had before as much as possible, but I would also like to return it towards what it might likely have been 200 or so years ago. Any input would be greatly appreciated.
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Old 03-10-2011, 07:07 AM
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Ken Smith Ken Smith is offline
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Cool wow..

That bass has seen some days. A sprung bar in a bass can cause a ton of damage to the top.

To re-shape a top in a mold you have to gut the entire top of all old work and brace it while making the cast to prevent collapse. This is what I have seen, not done so I will make that clear.

Breast patches should be 'feathered' in as opposed to inlaid straight down 'into' the wood as cutting 'down' into the grain of the top and inlaying wood with right angle inlays at 90 degrees can cause cracks along its own edges.

If you have a 10mm center then have him leave as much original wood as possible all around the inside and use as many breast patches inside the top where ever it seems thin based on that 10mm center and re-graduate it after all the breast work is down. It will look strange with all the wood feathering out into the old wood but don't be concerned with how it looks. I just had a German bass restored and it looks quite odd inside but it's graduated quite well.

The cracks under the patches will need to be glued first but if they are distorted and don't close, they should be veined in with small spruce. Sometimes while pressing a top out the cracks open again and again while working on the bass so be prepared for that. In the end all will be tight but, the bass will be like partly new again with all of the fresh wood.
Do not let fresh wood be a factor in graduating the bass to sound old when it's just newly restored. The bass has to break-in again and will take 2-5 years until you start hearing the old wood blend in with the new wood and sound as one. This has been my experience with old basses after major top repairs. Touch-up repairs including re-opening the Top are not unheard of either as the bass breaks back in all over again.

The sound of the bass just before the repair is the condition it has been in for the longest time. It will never sound 'exactly' like that again. It will have more focus in the sound and the old depth of tone will return slowly. My Cornerless bass was just re-strung after its long and detailed restoration and the depth from what Arnold described is not as deep as before but the focus as expected is improved. In time, that bass will mature again as the new wood mixes with the old.

So, be patient with the post-restoration sound and think of the bass's long term health while repairing the top rather than its immediate sound. The sound will come back.

This is the LeJune bass you once showed me, correct?

Also, repair the back and ribs as needed. After the top is fixed, it will be the weakest link that goes so make it all strong and check all the old existing work before closing up the bass. The bass needs what it needs and should never be repaired with limits in mind. I wish your bass (and you with it) the best of luck in its new and continued life.
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Old 03-10-2011, 06:26 PM
Dave Whitla Dave Whitla is offline
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Hi Ken,
Thanks for that Yes that is the LeJeunne bass- good memory!

Tom has been feathering in all the patches, so there should be no worries there. And he did undo all the old repairs before pressing it into the cast for re-arching. He also removed quite a few shims (up to 4mm worth in some places) to get the top fitting to itself properly. He had to remove some original wood to repair the woodworm damage, but with all the epoxy that was in there it probably wasn't really functioning properly anyway. He is trying to keep as much original wood as possible. In some places the worm damage/epoxy was almost through to the varnish.

Where the question arises is in the final stage thicknessing (is that a word?). Tom is a brilliant luthier, but he's looking for input for how to approach the graduation of the top once the final three patches are in. It seems like there are a lot of different possible approaches or patterns, and we are not sure how thick/thin to make the top to best combine what the original maker might have done with the long term health of the bass. Are there any luthier resources where we might be able to find out what the thicknesses of French basses of this age would have been? Or are these closely guarded trade secrets...

Also, thanks for the advice regarding my expectations of the sound post-restoration. I'm not really worried about all the new wood, because a lot of restrictive cross grained wood has been removed. But adjusting my thinking in terms of 2-5 years of 'break-in' will be a help. Intellectually I understand the necessity of all this for the long term health of my bass, but I still can't help hoping it isn't transformed too much. Thanks.
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Old 03-10-2011, 06:33 PM
Dave Whitla Dave Whitla is offline
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BTW, the back and ribs are in much better shape, generally. Three of the ribs were replaced at some point, probably when the shoulders were cut down. An airline broke the neck off a few years ago and the neck block was replaced and nearby areas of the back and ribs were strengthened. Hopefully this restoration will be the last major work for a long time...
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Old 03-11-2011, 12:31 AM
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Cool ok..

Like I mentioned in another Thread awhile back, I have not personally seen any 18th century French basses in person that I can recall. Only a few in pictures.

On your bass, 10mm center is on the thick side, not huge but some Panormo's are 6mm (all over) on the lighter side. I think 7-9mm center is more average but this also depends on the density and strength of the wood. The condition of the bass is important as well here.

Your Luthier has the bass in his hands. He has to determine what's best. If 10mm is the center then maybe go to 5mm or so at the edges but, measure what you have now. You can see the cracks on the bass and determine maybe what damage was from over thinning, what cracks are from Back movement and what cracks might be from accidents. Then with the estimated density and strength of the Top wood, pick a plan and stay with it. If this bass was thinned in the past then maybe you wont know what the maker did originally. The restorer has to map out the top now and make a plan for what might work for the future. Have him measure the current graduations in with circles and ovals from the center to the edges and bouts.

Later French basses (after 1850?) are notorious for being heavily wooded and in turn are often thinned down for tone and sometimes, too much so.
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Old 03-12-2011, 07:58 AM
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Matthew Tucker Matthew Tucker is offline
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Quote:
Originally Posted by Dave Whitla View Post
I would like to keep the beautiful, dark sound this bass had before as much as possible, but I would also like to return it towards what it might likely have been 200 or so years ago.
Those two conditions MIGHT be mutually exclusive!

I think I'd measure the existing grads and aim for them, and depending on what they are, and what the arching SHAPE is like, leave it a bit thicker all over. Like Ken says, you can always take some wood away later. Just make sure you glue the top on with thin glue!

Yep, unless you're going to double the whole inner surface you're going to have to feather the new wood into the old grads anyway. so that's going to force your hand a bit, unless you want lumps at the edges.
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Old 03-20-2011, 07:13 AM
Dave Whitla Dave Whitla is offline
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Thanks for your input guys.
I think the present thicknesses are very thin. As you can see from the 'before' picture above, there were dozens of cross grain cleats, straps, etc. keeping it together (and presumably restricting it from vibrating).
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Old 03-20-2011, 01:52 PM
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Cool thin..

Quote:
Originally Posted by Dave Whitla View Post
Thanks for your input guys.
I think the present thicknesses are very thin. As you can see from the 'before' picture above, there were dozens of cross grain cleats, straps, etc. keeping it together (and presumably restricting it from vibrating).
I had one modern bass that was quite thin all around but well graduated. The type of Pine used for the Top was very hard and dense strong wood. It seemed ok for the graduations vs. the density of the wood. So, softer or weaker wood needs to be thicker as well in comparison. Older basses might be the correct thicknesses or might have been overly thinned and need corrections. The life experience of the bass shows you what it likes and doesn't as does its tone as well in combination with its condition.
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