Bending owie's

C

ChuckBarnett

Well-known member
Joined
Mar 3, 2017
Messages
490
Reaction score
3
Location
Arlington, WA U.S.A.
My first experience building. This is a tenor ukulele with sides and back of quilted maple. On the inside of the waist of both left and right sides I have break out. I bent this with a bending iron at roughly 325 to 350 degrees. Also on the outside opposite of the breakout is a dimple in the wood. Somebody said, this being a figured wood, the dimpling won't be of much consequence. It won't be visible unless you're looking for it.
 

Attachments

  • 20170527_131553.jpg
    20170527_131553.jpg
    49.1 KB · Views: 102
You're brave to start with a very difficult material! Did you use a metal slat behind the bend to support the wood?
 
Not sure about brave… Cheap, mebbe. ;)

A couple years back I found a table top roughly 27” wide by 36” long. Had a pretty good bow in it (due perhaps to the top being finished and the underside not?). Top was laminated 1” x 6” solid wood and I figured I could rip the boards apart and resaw and perhaps get about 10” of width in a book-match back. So I paid $30 for the wood for the sides and back (enough for several if one is careful). That is a key reason I started building with a tenor ukulele.

On using a metal slat: I was unaware of that technique but am very interested! The videos I’ve studied are of people either with bare hands or gloves working over a bending iron. Didn’t see a support slat. I assume that would’ve helped?
Thanks!
 
Yes, when bending troublesome wood, which most figured wood seems to be, try putting a piece of metal behind the bend. Put your hands behind the metal and use it to apply the bending force to the wood. I use aluminum flashing that can be found in most hardware stores. Still, you can break the stuff but the flashing greatly improves the chance of success.

For sure, salvaged wood can sometimes make great instruments. Cheap salvaged wood is better yet.

I'm sure that a lot of the folks here will be interested in the progress of your first build, so keep us posted!
 
Thank you! And thank you for the tip.

I wonder if there's anything I need to do about the breakouts? Brian of Griffin Ukuleles suggested sanding them down and glueing a thin veneer over them on the inside. What has anybody done with this sort of a problem?
 
Put some CA in those areas and clamp them back down. Use some wax paper between the clamp and the wood. CA will stick to wax paper but you can sand it off.
 
Yeah, I would try and bend the sides back until the cracks close and do the CA glue thing. Then reinforce with cleats on the inside. The cracks just might look like grain lines. This is a good example of recovering after a boo-boo and making the mistake disappear. For me, building can seem like a constant recovery from tiny problems. You will learn on your first build that recovering is part of the building process. And then there are those things where no recovery is possible but this is rare. Remember: A good military maxim is: Know your lines of retreat. In other words: before you start doing something, keep in mind how you are going to get back to square one if things start to go bad.
 
I just repaired a similar one to that this morning on Koa about 10mm from the edge...the damage down to my stupidity :eek:..I used thin CA glue and a clamp..it can just be seen with very close inspection co's I know where it is ... but it looks like part of the natural grain and I hope it will be invisible after finishing.
It's in the centre of the pic at the side of the end block..the lining will support it and the binding will remove 50% of it ..I hope :rolleyes:
 
Last edited:
Had a newbee builder come over to my shop trying to figure out out why he was breaking just about every set he attempted to bend. He was beating his head against the wall for six months. He had been closely following the Hana Lima book. He said this book states that the sides should be 3/32" thick. Holy Cow!! that's damn near 100 thousands or close to 1/10th an inch. All other parts of his technique were fine but those 20 thousands of an inch were killing him.
 
Best not to produce that type of crack in the first place but the procedure for gluing that back would be to make two curved cauls, one for each side of that waist bend. Just glue and clamp. You may well get away without the need for those cauls. I wouldn't sand them down, what's the point? You've already got the perfect 'joint'. Personally I would use hide glue, sizing first. I'm sure CA will do the job but you might want the thicker type of CA. Just make sure you don't starve the joint, which can happen with thin CA.
 
I had to touch up a quilted sapele side before joining the two sides, so I took some photos to illustrate the method. Quilted sapele can be at least as troublesome as your maple but bending with a slat to support the runout grain works well.


34953351305_bbc7921d09_z.jpg


34953349035_66e22b9814_z.jpg
 
Successful hand bending is reliant on several factors:
1: Thickenss of material
2: Finished surface of material
3: Heat of the iron
4: Speed of bending

Wood is a thermo plastic and practically every piece will bend differently, react to heat differently and definitely cause problems if you soak the sides before bending, especially curly material. I'll bend some curly myrtle tomorrow and show you how to achieve this task without he use of water BUT, using a 'backstrap' to support the wood and transfer heat. And I wont be using gloves that will inhibit how I 'feel' the wood on the iron. You will have to get this over on the Facebook account of UU because I cannot download form my Mevo camera. It will go out live on my facebook group at 8.30am BST and I will share it to the UU page after boradcasting. Bit cumbersome but I don't have the time to shoot and edit anymore
.
 
I am new to this craft, but from all of the study I have done, it appears that most of the side sets I have seen and advice given in books is that best results are achieved using quarter-sawn wood. That piece in your photo looks like it may have been flat-sawn or otherwise. I started with some figured black walnut that looked similar and used a steam box to bend the sides. If I had that piece I would be tempted to soak it, flip it over, lay it on the iron until it conformed and then crazy glue it. But, that's me, the newbie.
 
As a newbie you then ought to refrain from giving bogus advice... I don't know anyone of repute who uses a steambox and would never advise anyone to soak figured wood for bending by hand - the irregular grain direction causes 'facetted' bending. Believe me, I've done enough of this to stand right by what I say -most figured wood needs to be bent dry - watch the video on it.
 
I did some curly maple binding the other day. Used a damp rag on the pipe and backstrap. Without the backstrap the wood would split.
 
You must log in or register to reply here.

Similar threads

Timbuck
More on heat bending.
Replies
10
Views
424
Moore Bettah Ukuleles
Moore Bettah Ukuleles
A
Side bending service
Replies
5
Views
437
rb4player
R
LabRat_3k
First time bending..
2
Replies
26
Views
1K
LabRat_3k
LabRat_3k
Pete Howlett
Side Bending - my 180
Replies
2
Views
466
Pete Howlett
Pete Howlett
Timbuck
Bending the waist of problem wood.
Replies
1
Views
314
DuckyI
DuckyI
Top Bottom