| Official Luthiers Forum! http://luthiersforum.com/forum/ |
|
| Fixing break in side http://luthiersforum.com/forum/viewtopic.php?f=10101&t=48121 |
Page 1 of 1 |
| Author: | MaxBishop [ Thu Aug 11, 2016 10:17 am ] |
| Post subject: | Fixing break in side |
I need some help here. I just bent the sides for a flamenco guitar commission. The wood is figured Lawson Cypress and bending caused a break in one side at the waist. I used Super Soft, wet the sides with water before bending - maybe I cranked down the bender at the waist too quickly? This is what it looks like from the outside. Attachment: Break outside.jpg Anyway, I'm looking for suggestions on how to glue it to ideally make the break invisible. Thanks, Max |
|
| Author: | profchris [ Thu Aug 11, 2016 11:39 am ] |
| Post subject: | Re: Fixing break in side |
I don't think invisible is possible. If I were making it as a player for myself and wanted to use the pair of sides, then I'd: 1. Hot hide glue a patch of 1/16 plywood on the inside, following the curve. 2. Slather hot hide glue in the cracks. 3. Back in the mould, heat gently, and crank down to try to get it to shape. 4. Once glue is dry, scrape the outside to shape and see how it looks. The cross-grain cracks would be visible, but under finish might look like creases from bending. Maybe a super-skilled person could scarf in a graft, or series of grafts, somehow matching the grain, but I couldn't. For a commission, I'd be looking for another pair of sides. |
|
| Author: | DanKirkland [ Thu Aug 11, 2016 1:06 pm ] |
| Post subject: | Re: Fixing break in side |
I've fixed this before on a finished guitar. I didn't take pictures unfortunately since it was on a short list to get done quickly. Chris is right it won't be completely invisible but we can fix it and make it presentable. I haven't worked with the wood you have but I was working with non figures maple. My method is as follows Cut a fill, (you can use filler too depending on the situation) get the fill as tight as possible glued into the crack with little to absolutely no gaps on either side. The tighter the better if you're using a wood splice, if you use a filler just ignore this step and fill it. Let it dry. Once dried sand it flush. Then take a very fine very stiff paint brush and color the grain pattern onto your patch. Use as close a color match as you can, stains work well for imitating grain lines as they aren't super bold. In this case you can just sort of connect the dots so to speak with the break in the grain lines. Draw your lines and let it dry, go.over it again if you need them to stand out a bit more. Rinse and repeat until you have a good match. Again this takes time and a steady hand. But you should have a good result if you're patient. |
|
| Author: | Hesh [ Thu Aug 11, 2016 1:15 pm ] |
| Post subject: | Re: Fixing break in side |
Hey Max! You should stop by one of these days and we can catch up. I'm afraid that this will show no matter what you do to repair it and if it were mine I would be replacing the sides. |
|
| Author: | Haans [ Fri Aug 12, 2016 2:56 pm ] |
| Post subject: | Re: Fixing break in side |
If it is a commission, replace the rib or ribs. You cannot hide that. What temp did you bend the waist? |
|
| Author: | DennisK [ Fri Aug 12, 2016 3:30 pm ] |
| Post subject: | Re: Fixing break in side |
Yep, new sides for this one. Use these as the inside laminate for double sides on something else. Maybe look for some nice Brazilian rosewood veneer that's too thin to build a guitar out of otherwise  You can still pair it with a solid back for tone quality, since BRW backs are easier to come across than usable sides.
|
|
| Author: | Joe Beaver [ Fri Aug 12, 2016 9:12 pm ] |
| Post subject: | Re: Fixing break in side |
Since it is a commission then new sides, if you can find a good match for the back. Otherwise new B&S. I suspect you already knew this but were hoping for a miracle. I don't blame you for that. I've been there a time or two. |
|
| Author: | MaxBishop [ Sun Aug 14, 2016 8:22 am ] |
| Post subject: | Re: Fixing break in side |
Thanks to all for your responses. I'm checking on some new sides. Max |
|
| Author: | talladam [ Sun Aug 14, 2016 6:47 pm ] |
| Post subject: | Re: Fixing break in side |
Just for my curiosity, is this crack because of the grain? To me it looks like there is a weird bit of grain there. I haven't really tried to bend anything like that though.. |
|
| Author: | MaxBishop [ Mon Aug 15, 2016 8:05 am ] |
| Post subject: | Re: Fixing break in side |
I don't think it was due to the grain. I am beginning to think I left the piece too thick at the waist. Max |
|
| Author: | Joe Beaver [ Mon Aug 15, 2016 12:16 pm ] |
| Post subject: | Re: Fixing break in side |
The other side bend ok? |
|
| Author: | MaxBishop [ Mon Aug 15, 2016 6:30 pm ] |
| Post subject: | Re: Fixing break in side |
The other one broke too - just on the inside. |
|
| Author: | Joe Beaver [ Mon Aug 15, 2016 8:06 pm ] |
| Post subject: | Re: Fixing break in side |
Some wood just doesn't want to be bent. Hate it when that happens. Is that the same as Port Orford Cedar? |
|
| Author: | MaxBishop [ Tue Aug 16, 2016 7:18 am ] |
| Post subject: | Re: Fixing break in side |
Yes. |
|
| Author: | MaxBishop [ Tue Aug 16, 2016 8:10 am ] |
| Post subject: | Re: Fixing break in side |
I just went through the current "Supersoft 2 AND water?" thread and the side bending Youtube tutorials linked inside and it looks like I used too much water. After using Supersoft 2 I put the sides in an envelope of kraft paper soakedwith water. Apparently this weakened the wood fibers enough so they ruptured at the waist while bending. Thus endeth this cautionary tale  Lesson learned.Max |
|
| Author: | Joe Beaver [ Fri Aug 19, 2016 7:37 pm ] |
| Post subject: | Re: Fixing break in side |
As they say, all's well that ends well....... Or as I like to say, it's not how bad things go that matters, it's how well you recover. |
|
| Author: | Mike OMelia [ Sat Aug 20, 2016 5:56 pm ] |
| Post subject: | Re: Fixing break in side |
I've looked at this a lot. To me, it's "over baking". |
|
| Author: | Woodie G [ Sun Aug 21, 2016 7:12 am ] |
| Post subject: | Re: Fixing break in side |
Did the side have excessive spring-back once removed from the bender, or was it close to the mold shape? If the side is bent late -after nearly all the moisture has been exhausted, and after the SuperSoft 2 has been baked out - the side will show excessive spring back once out of the bender. If this was more the case of fiber collapse with everything else done correctly for the bend, the side will likely show minimal spring-back once removed. What type of blanket is being used? Is it a 5 watt per square inch blanket, and is it being allowed to heat at maximum rate during the initial heat-up? We run the blanket at full through the completion of the bend, then to peak temp for the wood...we then throttle the blanket to maintain the desired drying temperature. A slow heat-up for rosewoods will usually not matter, but for woods that we bend with minimal moisture to avoid fiber collapse, such as curly mahogany, koa, and other highly figured woods, it runs the risk of exhausting the water before the bend. The reason to use butcher paper as a moisture reservoir is that it allows a much more consistent distribution of the right amount of water, although it also does a very nice job of picking up the excess resins from rosewoods. |
|
| Page 1 of 1 | All times are UTC - 5 hours |
| Powered by phpBB® Forum Software © phpBB Group http://www.phpbb.com/ |
|