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

Help with hole sanded into the side
http://www.luthiersforum.com/forum/viewtopic.php?f=10101&t=32856		 Page 1 of 2
Author:  Beth Mayer [ Wed Jul 13, 2011 5:17 pm ]
Post subject:  Help with hole sanded into the side
I closed the box on a tenor uke, flush-routed the overhang and have been sanding away to even the sides. I noticed what looked like a blemish in the edge of the treble side of the upper bout, but was concentrating on a spot closer to the waist. As I went on, I saw the "blemish" getting larger and when I looked, I had worn an apparent thin spot in the side right down to the kerfing. When I looked at the inside, I could see a line of light through just above the lining. [headinwall]
Not sure what to do. When I rout it for binding, the area won't be completely routed off, and I'm also concerned that the binding routing process may cause some chip-out to occur at that spot.
It is just off the maximum curve of the bout. I've attached a picture of it from the inside and the outside (my camera doesn't take closeups really well).
Thanks for any advise you can give. Beth
Author:  LuthierSupplier [ Wed Jul 13, 2011 6:17 pm ]
Post subject:  Re: Help with hole sanded into the side
I would add the binding, then add a black/white/black or black/white purfling under the binding. Just add purfling until it covers the hole. If you don't like black/white, then a thick maple under the binding or a taller binding of one solid color would work. You may have to get creative here, but it is doable. Good luck!
Author:  the Padma [ Wed Jul 13, 2011 6:25 pm ]
Post subject:  Re: Help with hole sanded into the side
Learning the skills of this craft can really be a hard pile of sawdust to suck up sometimes.

Well you probably gonna get a few dozen different "fix it" suggestions

starting with

patch on the inside...rather obvious

patch on the outside...real ugly. but can be covered with a dark burst finish.

wider banding.

let in rib rest ~ sort of like the let in arm rests.

Maybe a brass plaque engraved with something like..." Do not remove this plaque until the power switch underneath is first turned to the off position."

Start over.


Blessings
duh Padma
Author:  David Newton [ Wed Jul 13, 2011 6:54 pm ]
Post subject:  Re: Help with hole sanded into the side
First of all, I want to commend you for showing your mess-up for all the builder world to see, you must be a brave person.

Second, this little spot is just the part you can see, the rest of the side is too thin also.

Go ahead and finish it up however you want, and chalk it up to a learning exercise. You aren't the first one to do such a thing, nor will you be the last. You just are the first one to fess up to it.

Start another one real soon.
Author:  Beth Mayer [ Wed Jul 13, 2011 7:08 pm ]
Post subject:  Re: Help with hole sanded into the side
Thanks Tracy. It's beyond the kerfing so I wouldn't have anything to glue it to.
Padma....wisdom, as usual.
David...there's no room for ego when you really want to learn something. This feels like a pretty safe place to look for solutions and "fessing up" is part of that.
I'm not ready to throw in the towel. I thicknessed the sides to 0.08", but I had a raised spot there and spent too much time on it. I don't think that the sides are uniformly too thin. That said, the edge of the defect is obviously very thin, so I will have to use some kind of interior patch for it, if no other reason than to prevent tearout during binding routing.

Thanks for the responses! Keep 'em coming. Worst case...I'll learn another valuable lesson, as I have from all my mistakes. I have a refrigerator magnet that says "Never make the same mistake twice"! So far, so good!
Author:  B. Howard [ Wed Jul 13, 2011 7:44 pm ]
Post subject:  Re: Help with hole sanded into the side
This is a little out there, but have you considered veneering the sides. A 0.040" veneer would do nice and the bindings and purflings would cover the seem nicely. Would also mean that you would not be routing the bindings back to the kerfing, thereby maintaining what structural integrity is still there. We all make mistakes, it's how you recover from them that matters.
Author:  unkabob [ Wed Jul 13, 2011 7:46 pm ]
Post subject:  Re: Help with hole sanded into the side
This may be a dumb idea but why not add a raised binding. Maple veneer is around 0.024" thick and if made wider than the hole by an eighth or so could save the project. It may be unorthodox and ,for guitar builders orthodoxy is paramount, ukuleles are flexible. Think outside the box, literally. Then blend it in with sandpaper on a stick. I'll bet that it will sound at least as good when you are done.

I'm too cheap to let that much work and wood go to waste.

Bob :ugeek:
Author:  alan stassforth [ Wed Jul 13, 2011 8:34 pm ]
Post subject:  Re: Help with hole sanded into the side
Only solution I see is an inside reinforcement.
Move on,
and don't do that again!
Author:  Lincoln Goertzen [ Wed Jul 13, 2011 9:04 pm ]
Post subject:  Re: Help with hole sanded into the side
Hi, Beth,

I can't improve on the ways to fix this one, but the best way I know of to eliminate the problem on future instruments is this:

After you have the box glued up and the top and back flush trimmed, rout a channel into the top and back less than the thickness and height of your proposed binding scheme. That means, if your binding is .250" x .080", rout your channel about .200" x .060".

That will show you how far you are able to sand without problems.

I hope this helps, and I wish you well.
Author:  Steve Davis [ Wed Jul 13, 2011 9:20 pm ]
Post subject:  Re: Help with hole sanded into the side
I think its time for a florentine cutaway
for that lead ukeleleist!
Author:  DennisK [ Wed Jul 13, 2011 9:58 pm ]
Post subject:  Re: Help with hole sanded into the side
I'm not too picky about visual flaws as long as it sounds good, so I would most likely patch it. Take a piece of the back offcut, thin it down until it's nice and flexible, glue it on, and sand it flush. Make it pretty big so it reinforces the very thin area around the hole also. Try to match up the curl so it's not blaringly obvious.

Another option would be to reduce the depth enough that the binding will cover it. Peel the back and linings off, plane the rim and headblock down, glue new linings, and close it up again. But that would affect the sound more than the patch. Plus it's a lot more work.
Author:  dpm99 [ Wed Jul 13, 2011 10:19 pm ]
Post subject:  Re: Help with hole sanded into the side
As someone once said to me (and I have to remind myself of this all the time), the best way to make a fine guitar is to make ten lousy ones first. Make sure you post photos of the repair work!
Author:  Beth Mayer [ Wed Jul 13, 2011 10:22 pm ]
Post subject:  Re: Help with hole sanded into the side
Steve, I love that idea...more's the pity that I'm not (yet) gifted enough to do that.
Dennis, I like the idea of removing the back and shaving the rim down, but I think it would turn out too thin and, as you say, affect the tone adversely.
Unkabob, I did actually consider your option of a binding strip "outside the box", but I don't know how it will look.

I suppose I'll do the patch. The situation is a bit discouraging, but it's very heartening to have so many thoughtful responses. Thanks! [:Y:]
Author:  Mike Lindstrom [ Wed Jul 13, 2011 11:03 pm ]
Post subject:  Re: Help with hole sanded into the side
I feel your pain. I sanded a ukulele top so thin you could see though it. I don't have any good ideas to add to the discussion, but I'd vote for the oversized proud bindings. I'm picturing a sort of pop art cartoony looking thing. Could be cool. Might need that really expensive flexible wood to pull off what I'm imagining. Hard to clamp with the side that thin.

Mike
Author:  the Padma [ Thu Jul 14, 2011 1:55 am ]
Post subject:  Re: Help with hole sanded into the side
unkabob wrote:
It may be unorthodox and ,for guitar builders orthodoxy is paramount, ukuleles are flexible.

Bob :ugeek:



um Bob,

where did you get this pedestrian, cart load of B.S.* about orthodoxy is paramount for guitar builders? Common, were? Is not true! Common , show where its written! Is just old wives tales for them uninitiated in to our ancient craft of loofierisming and perpetuated by music store salesmen who will lead you down the garden path and even help swipe your credit card.

Orthodox pfft ...an't that some sort of religion anyways?


blessngs
duh Padma

Ps...me likes the extra banding idea.

* B.S. ~ Belief system
Author:  jfmckenna [ Thu Jul 14, 2011 7:47 am ]
Post subject:  Re: Help with hole sanded into the side
I did the very same thing on the second guitar I ever built, a 12-string guitar. The guitar had walnut sides. As a total noob I went down to the hardware store bought some walnut wood putty and filled it in. That was 21 years ago and I was just playing that 12-string yesterday :)

Not saying you should just fill it, it don't look pretty like that but I think you can patch it some how and still have a nice instrument for years to come. Since you can actually get your hands in there then patch it to reinforce the thin side. You probably have some side material left over so you can use that to create a patch for the outside. Try to orientate the grain as close as possible, cut out a rectangular section around the hole and install the patch.

The good thing is that this is on the downside of the Uke so you won't even have to look at it while you play ;)
Author:  the Padma [ Thu Jul 14, 2011 11:16 am ]
Post subject:  Re: Help with hole sanded into the side
Todd Stock wrote:
The problem with a sand-through like this is that the rest of the side in that area will be very thin, and given the hole is right on a stress riser (the edge of the lining), you can expect this to give you more in the way of problems on finishing and overall stability.

The fix? Pop off the back, strip the linings in the affected area, and laminate in a full depth patch from body wood.



Yes, this would probably be the "Ultimate" approach and that stress riser location is something to seriously take into consideration...However this approach as pointed out is not a song and a dance fix em up.

Now lets look at them kerfed linings....nice and chunkie and appear to have a nice wide surface that wold accept new linings after a suitable patch has been installed. The new linings on top of the old linings would IMNSHO (Ya me gotts a bg ego) eliminate the stress factor and hence the need to pull the back.

So there are things for you to consider here Beth rangeing from the quick and dirty hack of slap on some bondo and walk, all the way up to hard core pro job of pulling the back which is relatively easy. However attempting to remove linings glued to paper thin ribs well .....

If this was me, you know how me be doing it. Bondo! laughing6-hehe

If you go Stocks suggestion...ya may wanna get some serious steam happening so them ribs an lineings separate nice and easy.


Blessings
Author:  Beth Mayer [ Thu Jul 14, 2011 12:15 pm ]
Post subject:  Re: Help with hole sanded into the side
So Todd, you're saying that the patch alone, even if large, will not be sufficient without re-lining that area over the patch?

I do not want to do a shoddy fix. The wood was expensive, but more importantly, the end result is important to me. This uke is not for me (though I'm making it for the cost of materials to get the experience and the "owner" is aware of this). Even if it were for me, I want something I can be proud of and learn from. So, that's where I am coming from on this project.

Filippo had earlier suggested an internal patch. I thought I could do that successfully, so my plan for that was to bend a piece of body cutoff that was at least one inch longer on either side of the defect, and which would be nearly the width of the side, and patch that in and feather the ends. I would glue it's "back" edge to the lining to kind of minimally tie it in.
Before I do anything more (and while I prepare the patch) I'm going to continue to watch the discussion...it is very instructive. Thanks, Beth
Author:  Alain Moisan [ Thu Jul 14, 2011 1:36 pm ]
Post subject:  Re: Help with hole sanded into the side
Todd Stock wrote:
An internal patch is fine, provided it covers enough area to reinforce the thin area of the side. If it can be done through the sound hole, that's fine, but I suspect the better approach is to remove the back, trim off the linings (as mentioned, be gentle...preserve the side), double the side (might just be two inches worth of side...if you can bend a side, run the grain parallel to the side; if not, you could use two or three layers of appropriate veneer (try Woodcraft) running with the grain of the sides.


I agree with Todd. I guess it all depends on how you feel about your repair skills; removing a back and realigning it is not an easy job, and it may generate new and bigger problems than the one you have now.

If you go with the internal patch solution, I would try to gently chisel off the small portion of linings that is in line with the hole. This way you will be able to apply your patch all the way to the top and reglue lining on top of the patch. This will result in a repair with no fragile spot (stress riser). Of course, chiseling off linings on such a thin side is also tricky stuff...

Good luck!
Author:  SteveSmith [ Thu Jul 14, 2011 2:38 pm ]
Post subject:  Re: Help with hole sanded into the side
I'm certainly not one of the experts here but from the perspective of a newer builder I suppose if I was in this situation I would pull the back off (although I've not had a need to do that yet). Then you could remove part of the lining and measure the thickness of the sides to figure out how big the patch needs to be and do it up right. Good experience for you and lots of help from the experts here.
Author:  cphanna [ Thu Jul 14, 2011 4:19 pm ]
Post subject:  Re: Help with hole sanded into the side
Hey, Beth,
First, I agree with the notion of laying some veneer on the inside. You could put on a few layers, in fact, and have a nice, discrete, and strong structural repair. You could also add the tentalone or some other inside reinforcing brace.

Now, on the outside, I think The Padma actually had a very good idea that he camouflaged as a joke. (He has a lot of good ideas.) Why not call attention to the mistake? After reinforcing the inside, consider inlaying something on the outside. Maybe a little pearl leaf or something similar...right over the sand-through. When you're asked about it years from now you can say two things with absolute honesty: "I inlayed that leaf to prove to myself that I could fix any flaw. And I left it there as a constant reminder to myself that I mustn't make the same mistake again."

If you prefer to try to reinforce and then fill, you'd be surprised how easy it is to camouflage these areas with a little artist's oil paint. You'll have to practice to get the colors right, but you can do an amazing touch up that way. I chickened and did that on a layered, wood binding sand through once.

Good luck with it.

Patrick
Author:  jfmckenna [ Thu Jul 14, 2011 10:25 pm ]
Post subject:  Re: Help with hole sanded into the side
Beth Mayer wrote:
So Todd, you're saying that the patch alone, even if large, will not be sufficient without re-lining that area over the patch?

I do not want to do a shoddy fix. The wood was expensive, but more importantly, the end result is important to me. This uke is not for me (though I'm making it for the cost of materials to get the experience and the "owner" is aware of this). Even if it were for me, I want something I can be proud of and learn from. So, that's where I am coming from on this project.

Filippo had earlier suggested an internal patch. I thought I could do that successfully, so my plan for that was to bend a piece of body cutoff that was at least one inch longer on either side of the defect, and which would be nearly the width of the side, and patch that in and feather the ends. I would glue it's "back" edge to the lining to kind of minimally tie it in.
Before I do anything more (and while I prepare the patch) I'm going to continue to watch the discussion...it is very instructive. Thanks, Beth


The non shoddy fix would be as I tried to describe earlier. It's similar fix to repairing a guitar that had a hole poked through the side. You cut out around the hole a square or rectangle and patch it with a piece with the closest grain match you can get. Being that you probably have side extras then that's real close. I'd think since it looks like it's on the upper bout and accessible through the sound hole that this would be easier then removing the back, especially if the back is already bound.
Author:  alan stassforth [ Thu Jul 14, 2011 11:33 pm ]
Post subject:  Re: Help with hole sanded into the side
I think you should take the back off as well.
Clamping the patch would be a lot easier.
Nice tighter joint.
If the back doesn't line up very well,
you might need a purfling along with the new binding.
DAMHIKT.
Author:  jayluthier [ Fri Jul 15, 2011 4:54 am ]
Post subject:  Re: Help with hole sanded into the side
After over 40 years of building instruments, I must say that one of the most painful lessons that i finally learned was the ability to recognize when it was best to just "walk away." I'm a little surprised that no one has mentioned this option.

In my experience some instruments just don't want to be built. It's a bit like fixing an old car: first you change the valve cover and then the head starts to leak. You then do a valve job and the rings take a hit. Once you've replace the rings, then the oil pan decides to leak.
My point is that unless your objective is to make this an endless 'learning experience.' one can easily end up spending way more time and aggravation trying to fix a problem, than just simply stopping.

For me, stopping has come to mean that for the sand-through to the lining which happened to me more than once since I'm such a slow learner, you get to a point where you''re better off taking the uke (or guitar) body to a one-way meeting with your bandsaw. Then, quite deliberately, saw the body in enough pieces so you are not
the last bit tempted to try to fix it. Then with your newly acquired lesson to not sand so often "just to see how it will look" during the course of the build, start a fresh, new instrument.
While this may sound harsh and will probably invite criticism from some other forum members, I can say from experience that for me, when I learned when to stop chasing my tail with a fix, and just walked away, it was extremely liberating. And, you know, it's only a bit of wood!
For this sand-through, the only acceptable solution short of the guillotine approach- for me - has been to make a new side. And, actually if you really want to save the back and top, you can carefully disassemble the box and reuse the top and back for you next attempt.
I would walk away.
OK..forum police - criticize away.
Author:  jfmckenna [ Fri Jul 15, 2011 7:18 am ]
Post subject:  Re: Help with hole sanded into the side
laughing6-hehe I've definitely taken the band saw approach myself. Since this instrument is for some one else after some consideration I agree, it should be done up right. The other option is, fill it, keep it for your self, and build another one.
Page 1 of 2 All times are UTC - 5 hours
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/