Bent side "spring back"

Tudorp

Big guy with a lil' uke..
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When bending sides. Is is normal to have at least a little spring back when taken out of the form? If so, how much is too much? What does this mean? Not bent properly? Not enough heat? Not enough time in the form? Does it have to be heated and bent again and back in the form?

Thanks in advance for the input..
 
Im not sure what the actual temp was on my hot pipe, but I gauge it by spritzing water on it. it the water sizzled, and dances off, I figure that the heat is hot enough. I just noticed on a couple sides I bent the other day, they sprung back a little bit, but not much. I was able to put them back in the form without any problem or overstressing the wood to get them back in. I was just wondering if they spring back a little bit, if that should be expected.
 
I find that it really depends on the wood species as to spring back. Almost all of the Aussie woods I use take the "set" very well with bugger all spring back. Then there are some other types that I've been using like Honduras Rosewood and Zircote that have a fair bit of spring back and I always end up touching them up on the hot pipe.
 
You can't just bend the sides until they can be jammed into a mold then leave them to set like jello in a mold. The mold is simply to hold your side to a precise curve, not to keep it going flat. Different timbers are different, some will just set where you leave them, others will fight to move.
Try using you're hot pipe to get the side as close as possible them pop it in the mold for a few days to dry. Then come back and touch it up very dry so that you don't introduce more water that can cause the side to move around again.
 
Im not sure what the actual temp was on my hot pipe, but I gauge it by spritzing water on it. it the water sizzled, and dances off, I figure that the heat is hot enough. I just noticed on a couple sides I bent the other day, they sprung back a little bit, but not much. I was able to put them back in the form without any problem or overstressing the wood to get them back in. I was just wondering if they spring back a little bit, if that should be expected.

I just know that with koa I will get some springback if I don't remove all of the water through the bending process, no matter what temperature I get it to. Water removal without burning is a function of time and temperature.
 
All that makes sense.. I took my sides, and wet em, and reheated them on the pipe until they were good and dry by letting the pipe heat the water out of them, and placed them back in the "die/press" type of mold I made for them. Let them set for a few hours, and removed them, and they seemed to stay with next to no spring back this time. They should probably stay in there for a day or so I assume? But I placed them in the assembly jig, and clamped them in there for a day. Maybe tomorrow, or next day, I can glue the back on. But the re-heat and dry seemed to set them now pretty good. I just wanted to be sure that there is no stress on the fibers before I actually started the gluing and assembly. Thanks for the feedback and advice guys..
 
Nothing quite like a good bending setup with heat on both sides and then doing two complete cycles of heat; the first the basic bend with moisture, the second done after the sides have cooled down and done dry at maybe a bit lower heat. The thing about a good double (or more) stainless steel slat bender is that you can "set" the bend and completely dry out the sides under pressure in the bender. You can't really do that with a hot pipe.

I think if you're serious about building ukes, you should be super-serious about building the right jigs and fixtures to make the uke making easy. You'll get better results.

Ideally, we're making perfect uke kits and then building perfect ukes from those kits. The better your parts are, the better the final result will be. Newbie builders are just so impatient to get results that they frequently blow right past the steps that make good results easy.
 
Agreed. Somehow it bothers me when I see new builders wanting to jump right into building without getting set up properly from the beginning. Even buying, or paying someone else to make their molds. That part I just don't get. I think before you bend your first piece of wood or attempt to carve your first brace you should spend a couple of months making all the jigs and molds you need. If you are new to lutherie (or even wood working), what better way to learn the necessary skills which will be even more demanding when you actually start building.
Make lots of molds. It's good experience and you'll get better with each one you make. IMO, your finished mold should look at least as good and be as perfect as you expect your finished uke will be. Your finished uke will only be as good as the mold in which is was made. If you've got kinks or flat spots in your mold, they'll be there in your uke too.
And do your homework. It's all out there. Twenty five years ago I learned to build from a guitar parts catalog (probably Stewmac) figuring things out from there. Today with the Internet it is so easy to get up to speed with everything you need to know. When you are equipped with sound technical information and well executed forms and jigs it greatly improves your chances for success, making building easier and even fun instead of a frustrating series of mistakes. There are no short cuts to doing the work.
 
Agreed. Somehow it bothers me when I see new builders wanting to jump right into building without getting set up properly from the beginning. Even buying, or paying someone else to make their molds. That part I just don't get. I think before you bend your first piece of wood or attempt to carve your first brace you should spend a couple of months making all the jigs and molds you need. If you are new to lutherie (or even wood working), what better way to learn the necessary skills which will be even more demanding when you actually start building.
Make lots of molds. It's good experience and you'll get better with each one you make. IMO, your finished mold should look at least as good and be as perfect as you expect your finished uke will be. Your finished uke will only be as good as the mold in which is was made. If you've got kinks or flat spots in your mold, they'll be there in your uke too.
And do your homework. It's all out there. Twenty five years ago I learned to build from a guitar parts catalog (probably Stewmac) figuring things out from there. Today with the Internet it is so easy to get up to speed with everything you need to know. When you are equipped with sound technical information and well executed forms and jigs it greatly improves your chances for success, making building easier and even fun instead of a frustrating series of mistakes. There are no short cuts to doing the work.
All good advice..there Chuck:agree:..I built a Fox type bender first and then my neck turning jig... then a Solera..then i produced my first uke :) and then I scrapped it co's it wasnt good enough.:(
 
Thats true, myself included. I think anything you go into with excitement, ya tend to do that. It's good to get excited, but even better to calm down and think about how you will tackle it, and reserach. I saw the same thing with hot rods. I have built many vintage hot rods over the years (yeah, I'm an old gear head, grease monkey). My 1st hot rod I built with my dad when I was 14. He was seasoned, and of course was there by my side to keep me from getting too excited and make stupid mistakes, but my 1st on my own, I remembered what my dad taught me about cars, and mechanics, and did well, but there were still those little stupid mistakes. Each one I built over the years were more and more inovated, and better than the last. As I matured into a veteran hot rod builder, I would see the younger guys and newbies make the stupid mistakes because of their excitement and rush to get their car done. I think anything ya do with your own hands with the type of people that do work with their hands must be that way. Now that I am 50, and new to getting into something new for me, I see that 14 year old hot rod builder frothing at the mouth again, hahhahh.. Thanks guys, all good advice. I need it since my Dad is no longer here to slow me down.. ;)
 
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