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Pete Howlett
06-19-2014, 09:30 AM
This bubbly, irregular wide-flamed koa was hand bent on an electric hot iron.

http://i1269.photobucket.com/albums/jj589/HowlettUkulele/81d6d415-d7d9-4796-9689-020204ad316d_zpsf994ba78.jpg (http://s1269.photobucket.com/user/HowlettUkulele/media/81d6d415-d7d9-4796-9689-020204ad316d_zpsf994ba78.jpg.html)
If you are starting on this 'lutherie' journey instead of running for the heat-blanket aisle, I suggest you invest in a bending iron (found in the LMII catalogue under the curious category 'free form bending') so you can learn why crazy wood like this can bubble, split and crack even when you bend it using Chuck's excellent method. Sadly, you will be doing this without his immense experience working this stuff...

Part of the trick or skill if you will to bending is knowing 3 things-

Required bending thickness - not always the same
Degree of heat required - just a smidgen too much on the dial will scorch koa
Grain/figure orientation - where to put the awkward bits...

I do use machines to set bends but still get a great delight from hand bending, especially on a cold morning in the workshop. When I made sopranos I'd start them off on the iron and finish them in a machine - the only way to make symmetrical straight sides for binding and border decoration.

Being a builder is not about applying theory or trying someone else's techniques (though this path is so essential - in industry they call it mentoring). It's about learning a craft, developing that learning by evolving a basket of basic skills that helps you get to the point where you are confidently producing consistently good results. I've been really encouraged lately by some new builds posted here - inspiring first timers who clearly have talent. However 'one swallow does not a summer make'. Despite having reached a point where I think I am beginning to get it right more than I am missing the point, there are always rainy days: the set in the above image was the 2nd consecutive one from the pile - I cracked the first because I ignored my 3 basic steps in the excitement of getting a new bending iron which I hadn't properly road tested to find it's ideal working temperature! - A Sad but True story :)

ksquine
06-19-2014, 09:46 AM
Yep...I'm a big fan of bending irons. I broke or wrinkled more sides when I started out with a heating blanket than I have with a bending iron. The best part is the feel when the wood turns plastic and bends.
I would advocate building a bending iron for the hobby builder. Those professional irons are nice but quite expensive. All you need is a pipe, a heat source (torch, heat gun, charcoal starter) and some boards to hold the parts together. $20-50 bucks and you're ready to go. But yeah....practice on some scraps before committing your high-figure koa

Moore Bettah Ukuleles
06-19-2014, 10:32 AM
Yes, you've got to learn how to bend on a pipe before using heat blankets. You'll learn a lot more about it when you can actually feel, see, hear and small what the wood is doing. On the few occasions when I do hand bend I prefer the torch/pipe over my electric bender because it's much faster (also a lot more dangerous). If I were doing a lot of them, like Pete is, I'd probably use the electric iron and leave it on for a couple of hours. I'd use it more often if it didn't take 20 minutes to heat up.

Timbuck
06-19-2014, 11:04 AM
I prefer the torch/pipe over my electric bender because it's much faster (also a lot more dangerous). If I were doing a lot of them, like Pete is, I'd probably use the electric iron and leave it on for a couple of hours. I'd use it more often if it didn't take 20 minutes to heat up.
Chuck... it only takes a a couple of minutes to heat up an electric iron....You just preheat it with the propane torch...I've been doing it for the last couple of years with no problems.

Allen
06-19-2014, 11:16 AM
I'm bending the same as you are Pete. Those tight bends in the waist and upper bout on my instruments are just too severe to go straight to the solid form and heat blanket.

I find it very relaxing to hand bend, and it does make for one of those "magical" demo's when people come around the shop to see what a luthier does.

resoman
06-19-2014, 11:24 AM
I've been building some dulcimers and have been bending with the iron and I really like doing it this way. I'm getting faster every time and now am starting to do some of the uke sides with it. Like Allen I find it relaxing and there is so much less prep involved
I've been using a heat gun to get the iron up to temp

Pete Howlett
06-19-2014, 11:47 AM
It's hard to put across the sense of Zen-like peace and tremendous satisfaction you get when it all goes to plan, especially if you are tackling a gnarly piece of wood that is putting up a fight!

Timbuck
06-19-2014, 11:48 AM
I usually have no problems with the one inch radius on my soprano waists..apart from the last batch of Honduran mahogany that gave me wrinkle problems and I got that sorted in the end..I do these with the Foxy type bender that I made...The mould part of this bender is made from solid aluminium with 10mm carbon steel heat retaining rods at a 25 mm pitch..I don't use heat blankets, just halogen ...if I did use heat blankets I'd use them under the steel slats as heating elements, not in contact with the wood...after bending I have to sort out the radius at the top and bottom co's I didn't allow for it in the design of the bender and they end up flat...I do this in the electric bending iron, it just takes a few minutes.

Moore Bettah Ukuleles
06-19-2014, 12:15 PM
Chuck... it only takes a a couple of minutes to heat up an electric iron....You just preheat it with the propane torch...I've been doing it for the last couple of years with no problems.

That's a great tip. Thanks!

Chris_H
06-19-2014, 12:15 PM
I bought 3- 2" x 8"+ x 6' long adjacent boards from the same log as the board that Pete is showing right there. That stuff is very tricky to bend, way more difficult than some other very curly Koa that I have. I broke 5 sides in a row before needing to ask for help on how not to break it. I can bend it now in the machine using 2 blankets and 4 slats,

rudy
06-19-2014, 02:36 PM
I enjoy hand bending occasionally, and once I figured out that you ALWAYS need a back-up strap for wood to bend into and against my success rate skyrocketed.

Pete Howlett
06-19-2014, 03:08 PM
It also helps to know your shape and where on the iron the corresponding curves are. Excellent advice Rudy -I use a short stainless steel shim for supporting tight bends and crazy curl.

Red Cliff
06-19-2014, 10:23 PM
I recently moved up from using a hot pipe to an LMI type bending iron. But being in the UK they work out expensive - I found a company called Caramillo in the UK run by a chap called Andy Wheeldon who teaches at Newark College on some of the instrument making courses and makes guitars.

He makes them himself - here is a youtube video of how it is done which is well worth a watch: http://www.youtube.com/watch?v=JGjGFYEs9-0

I got a 'Brady' model which has curves suited for both guitar and ukulele making - but he can custom make stuff as well - worked out at 130.

The attachment is a picture of what they look like - although not the model I got. Well worth considering if you are Europe based - well made.

I should say I have no interest in Caramillo other than being a happy customer

Timbuck
06-20-2014, 01:46 AM
We did a thread on bending irons a while back ... See here http://forum.ukuleleunderground.com/showthread.php?80095-Electric-Bending-Iron-from-e-bay&highlight=bending+iron

Flyfish57
06-20-2014, 07:03 AM
I bent my first 10 or so sets on my iron. Around set four I thought I had it all figured out. That's when I had a side of Honduran Mahogany shatter...It didn't crack, but more like exploded! Now, when I bend a set by hand, that's the first thing that still comes to mind.

ukuleleCraig
06-20-2014, 02:08 PM
I recently moved up from using a hot pipe to an LMI type bending iron. But being in the UK they work out expensive - I found a company called Caramillo in the UK run by a chap called Andy Wheeldon who teaches at Newark College on some of the instrument making courses and makes guitars.

He makes them himself - here is a youtube video of how it is done which is well worth a watch: http://www.youtube.com/watch?v=JGjGFYEs9-0

Thanks for this info Red Cliff and the great link. Always nice hearing about suppliers that are local.

Red Cliff
06-20-2014, 09:36 PM
Thanks for the link to the bending iron thread Timbuck - have added a post there.

Michael N.
06-20-2014, 11:19 PM
It can be quite surprising just how fast one can get bending sides on the old iron. There was a time when I considered making a bending machine but I soon came to the conclusion that I do far too many different shapes. The time spent on making the moulds would not have been worth it.
Last week I bent 3 sets of Guitar sides - 1 Rosewood, 2 Walnut.
The first rosewood side took me 35 minutes, the 2nd rosewood 10 minutes. The rest were 10 minutes each except one of the Walnut sides which took an astonishingly low 5 minutes. That's not to boast but to reinforce how fast things can go when the 'eye' is in.

Vespa Bob
06-24-2014, 02:28 PM
When I first started building, I tried a few unsuccessful methods of heating a pipe, but once I purchased a good heat gun, my problem was solved. It's a Wagner with multiple heat settings which allows rapid heating of the pipe, then backing it down to a working level. For novice builders out there (like me) this photo may give them the idea:

bigphil
06-24-2014, 04:28 PM
Good info here if I get around to trying another uke build I may give hand bending a try.

I was pretty surprised on my trip to Oahu this year to discover KoAloha bends all their sides on a pipe. What was more surprising to me is that the sides are cut to final size first! I specifically asked about this after seeing the side pieces all neatly trimmed in the flat.

Having built nearly one uke, I'm not any where close to that skilled. ;)