Maple side crack, any suggestion ?

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Valben
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Maple side crack, any suggestion ?

Post by Valben » Mon May 21, 2018 1:01 pm

Hi All, this is the first time I have tried to bend a maple cutaway side. Result in the pic below :-(
Not sure what I have done wrong, I have used the same method I have used for other woods like Blackwood, Lacewood, Myrtle, Purpleheart and Rosewood. the only difference with Maple is that I have thicknessed the cutway portion of the side to 1.9mm.
Any suggestions about possible repair method or I shall I start the fireplace ?
cheers
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IMG_20180520_113152.jpg

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kiwigeo
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Re: Maple side crack, any suggestion ?

Post by kiwigeo » Mon May 21, 2018 1:28 pm

Others may have ideas but generally when I get to this stage the side gets chucked back on the shelf or in the fire. Are you bending with a blanket and form or free hand on an iron? I always have fun bending the cutaway horn on my Gore style steel strings. Im bending Rosewood and do it freehand on an iron but always find it challenging. I trashed 4 sides on my first Gore build...the last one I managed to get bent on first attempt. All I can say is good luck :)
Martin

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Re: Maple side crack, any suggestion ?

Post by blackalex1952 » Mon May 21, 2018 1:54 pm

Well, there are many more experienced luthiers on this forum than me. But in my experience this kind of cross grain tear is pretty much destined for the trash. I once tried as an experiment, to repair a similar split with superglue then continue bending, but the fumes are horrible when hand bending and probably a serious health hazard once the side is back on the iron. I also have found that a bending strap is a sound investment when hand bending if that's what you are doing. In fact any method of bending using something which keeps the heat and the moisture evenly through the timber is the way to go. Eg. alfoil wrap around the piece or a wet towel or even a scotchbrite pad on the top side of the wood. The issue, I suspect, is that the wood dried out too quickly while it was being bent, I usually soak the timber first in hot water with a little hair conditioner to be safe. I also spritz with a water spray if not wrapping the wood in foil, as the bend takes the moisture out. After the bend I immediately clamp into the side mold to cool, then if necessary, refine the bends on the iron after that if necessary. I know a luthier who is highly respected who boils his sides before bending. There is also a tute by Robbie O'Brien on this forum and on youtube called "pandoras box". Cneers, Ross
https://www.youtube.com/watch?v=rqSglfu6xtA
"Everything I say on the topic is based solely upon inexperience and assumption!"

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Valben
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Re: Maple side crack, any suggestion ?

Post by Valben » Mon May 21, 2018 3:20 pm

Sorry , I have just realised that I have missed some vital information:
I use a blanket on a bending form and, when required, I retouch the side by means of a bending iron using a stainless support strap.
This crack has shown-up out just out of the bending form.
In the past (few) cases bending cutaways I actually had no problems except for some pressure marks on the inside of the bends, that have been easy to repair.
I was thinking about preparing full depth inner and outer forms and use some 30min clear epoxy with strong clamping.
If it solves the problem I can then use the same epoxy as pore filler on both sides and back before starting the finishing process thus to match the final colour tone.
If it doesn't solve the problem then I will just procure another maple set and try one more time :-)

Many thanks for the prompt answers/suggestions received till now, I am new in this forum and very impressed with the technical topics being discussed. I will definitely contribute as much as my modest experience allows :-) cheers

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Allen
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Re: Maple side crack, any suggestion ?

Post by Allen » Mon May 21, 2018 4:32 pm

I think that you will have a devil of a time trying to hide that in a repair unless it's getting some serions sunburst treatment.

For tight bends like cutaways or those on ukuleles, I'd go down in thickness a bit more. Like 1.7mm.

That and I always bend them on the iron first. I have much more feel there for what the wood is willing to do. You just have to get them close to shape. Afterwards you can put them back on the form and finish setting the shape without fear of breaking them.
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colburge
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Re: Maple side crack, any suggestion ?

Post by colburge » Tue May 22, 2018 7:29 am

Throw it away, it isn't worth the effort. It is frustrating, I have done it and tried to repair with epoxy or CA and it just turns out horrible.

Col

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Valben
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Re: Maple side crack, any suggestion ?

Post by Valben » Tue May 22, 2018 9:48 am

Hi guys, thanks for all the suggestions. It is difficult to give up to a nice (and costly) piece of timber like that but will follow your suggestions and use my time to something more productive. Cheers

Fisherman
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Re: Maple side crack, any suggestion ?

Post by Fisherman » Tue May 22, 2018 12:55 pm

Could be repurposed as ukulele sides? Probably 2 sets...?

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kiwigeo
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Re: Maple side crack, any suggestion ?

Post by kiwigeo » Tue May 22, 2018 6:01 pm

Fisherman wrote:
Tue May 22, 2018 12:55 pm
Could be repurposed as ukulele sides? Probably 2 sets...?
If the crack is towards the end of the side then yes it can be used for a uke or chopped up for use as bridge patches, soundhole reinforcement patches etc.
Martin

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Valben
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Re: Maple side crack, any suggestion ?

Post by Valben » Fri Jun 08, 2018 12:03 pm

sometimes I am stubborn but it didn't feel right to waste a so nice maple set, so here the solution I adopted which consists on a cross between Florentine & Venetian cut-away :-)
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IMG_20180602_103239.jpg
IMG_20180602_103258.jpg
IMG_20180602_103245.jpg
IMG_20180604_163048.jpg

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colburge
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Re: Maple side crack, any suggestion ?

Post by colburge » Fri Jun 08, 2018 4:08 pm

Great solution, well done.

Col

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kiwigeo
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Re: Maple side crack, any suggestion ?

Post by kiwigeo » Fri Jun 08, 2018 8:59 pm

Bldi hell....I never would have thought up that one. Bravo...well played!!
Boe Jonamassa wrote:
Fri Jun 08, 2018 4:08 pm
Great solution, well done.

Col
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Fisherman
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Re: Maple side crack, any suggestion ?

Post by Fisherman » Sat Jun 09, 2018 1:29 pm

I’d still hoick them...

Just kidding! That is a great way to turn it into a design feature.. looks great - cant wait to see how the whole thing looks when it is finished.

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Re: Maple side crack, any suggestion ?

Post by Jim » Sun Jun 10, 2018 8:58 pm

+1 on the well played!

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lamanoditrento
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Re: Maple side crack, any suggestion ?

Post by lamanoditrento » Mon Jun 11, 2018 8:45 am

Love the problem solving! Well done :cl
Trent

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Francis
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Re: Maple side crack, any suggestion ?

Post by Francis » Wed Jul 11, 2018 2:42 am

Really great solution to that problem.

I've had a couple of sides crack and I've put it down to not allowing the side to heat through enough and applying pressure too far from the point of bending - probably a combination of both!

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