Side bending alternatives...

Talk about musical instrument construction, setup and repair.

Moderators: kiwigeo, Jeremy D

Post Reply
Insomnomaniac
Myrtle
Posts: 80
Joined: Fri Oct 15, 2010 6:17 pm
Contact:

Side bending alternatives...

Post by Insomnomaniac » Sat Oct 22, 2011 12:43 am

Ok, after some pretty major financial setbacks, I am FINALLY getting around to starting on my first uke...

Money is still very tight, so I'm trying to save some money where I can. Being a carpenter I have most of the tools I will need (or at least ways and means of improvising) but one thing which is throwing me a little is a side bending iron. I don't want to spend $250-300 (plus shipping) on a side bending iron which I may not end up using very much (straight away). Can anyone suggest a workable alternative that won't break the bank? I work at Bunnings, so anything I can source through there would be an advantage (staff discount and all...).

Help!
Ian

Carpenter turned Knifemaker, now tentatively trying Luthiery as yet another hobby on the list...

User avatar
WaddyT
Blackwood
Posts: 231
Joined: Tue Apr 15, 2008 1:49 am
Location: Charlotte NC
Contact:

Re: Side bending alternatives...

Post by WaddyT » Sat Oct 22, 2011 2:12 am

I know stuff is different where you are, but here is the one I made. My cost is less than $50. Parts = truck replacement tail pipe section from auto supply store (cut in half, split one half down the length and squeezed it inside the other half for mass), scrap wood, electric charcoal starter from a home improvement center (squeezed to fit in pipe), grill thermometer, jar lid in end, and finally a router speed controller for temperature control. I have a blanket and you can see the form, which I use as a check for my bending, but I still (working on #10 now) use the iron and hand bend. It's just too easy, and I get no spring back.
P1030062 (Large).JPG
P1030062 (Large).JPG (71.37 KiB) Viewed 20333 times
Waddy

Build Albums 12 done - 1 in process

Clip for #1 Barrios' "Una Limosna por el Amor de Dios" - Not me playing

jeffhigh
Blackwood
Posts: 1536
Joined: Thu Feb 07, 2008 5:50 am
Location: Caves Beach, NSW
Contact:

Re: Side bending alternatives...

Post by jeffhigh » Sat Oct 22, 2011 5:06 am

Where are you located Ian, there may be someone close who will let you use their iron.

User avatar
Sean Syman
Wandoo
Posts: 19
Joined: Thu Jul 14, 2011 10:15 am
Location: Christchurch, New Zealand

Re: Side bending alternatives...

Post by Sean Syman » Sat Oct 22, 2011 7:39 am

First time I bent sides, I steamed the wood in this, which would have cost us maybe $10 to put together;
DSCF0503.JPG
It's sitting over a boiling pot on a gas cooker with a lid that channels the steam up into the aluminium ducting. The wood was then wrapped around some pegs on a form to create the bend. It did the job, but a bending iron is much easier and better, much less spring back (although a bending iron doesn't look like a missile launcher!). Jeff's idea of borrowing the use of someone else's would be the way to go if you don't want to spend the money (that's what I've done), but there are other ways.

Cheers, Sean

User avatar
woodrat
Blackwood
Posts: 1154
Joined: Tue Nov 25, 2008 6:31 am
Location: Hastings River, NSW.
Contact:

Re: Side bending alternatives...

Post by woodrat » Sat Oct 22, 2011 8:11 am

Sean Syman wrote:First time I bent sides, I steamed the wood in this, which would have cost us maybe $10 to put together;
DSCF0503.JPG
It's sitting over a boiling pot on a gas cooker with a lid that channels the steam up into the aluminium ducting. The wood was then wrapped around some pegs on a form to create the bend. It did the job, but a bending iron is much easier and better, much less spring back (although a bending iron doesn't look like a missile launcher!). Jeff's idea of borrowing the use of someone else's would be the way to go if you don't want to spend the money (that's what I've done), but there are other ways.

Cheers, Sean
Hi Sean, You know you are the first person that I have seen use this technique in lutherie (surely there must be others). It is a technique more associated with boat building and furniture making than lutherie but I cant see why it shouldn't produce the required result. Thanks for showing us the pic.

John.
"It's never too late to be what you might have been " - George Eliot

User avatar
Sean Syman
Wandoo
Posts: 19
Joined: Thu Jul 14, 2011 10:15 am
Location: Christchurch, New Zealand

Re: Side bending alternatives...

Post by Sean Syman » Sat Oct 22, 2011 10:23 am

I come from a sailing family, so we just made use of what we know. The spring back is a real problem, I was using this to bend a teardrop shape for a Weissenborn and cooked the sides for at least half an hour. I can't see this process working so well for tighter bends around the waist, especially for a uke, but it's cheap enough to give it a go.
DSCF0512.JPG
DSCF0512.JPG (163.78 KiB) Viewed 20290 times
Here's the form I used, the touching faces of the pins are curved to the match the curve of the side. I didn't have any problem with splitting, the sides would have been about 2.2mm and could have been thinner to make bending easier.

User avatar
graham mcdonald
Blackwood
Posts: 473
Joined: Thu Oct 25, 2007 11:57 am
Location: Canberra
Contact:

Re: Side bending alternatives...

Post by graham mcdonald » Sat Oct 22, 2011 1:06 pm

A length of 50mm diameter pipe and a propane torch. Should work just fine for ukes.

cheers
Attachments
bending_kit.jpg
Graham McDonald
http://www.mcdonaldstrings.com

User avatar
auscab
Blackwood
Posts: 650
Joined: Wed Jan 12, 2011 1:12 am
Location: Melbourne Australia

Re: Side bending alternatives...

Post by auscab » Sat Oct 22, 2011 5:03 pm

Hi Ian,
Just an idea, that could be the cheapest way to go.
I read once where an old way of bending was done in a brass pipe in which cotton wool balls soaked in metho were thrown in, the pipe was held vertical on the bench. it got me thinking that if you didn't have welding or brazing capabilities it could work like this picture.
If you got 800 mm x 75 mm pipe
plugged 50 mm at one end with silicon pink

Then drill breather holes ,four maybe half way up.

Pack just below the breather holes down to the silicon with a rag Green

Bury the pipe in the ground to just below the breather holes, pour in metho till the rag is fully soaked and light from the breather hole . the first time you light it it should be a gentle start up,when the first lot of metho is finished be careful when the second lot goes in to the hot pipe ,it will heat the metho and the slightest spark could set it off with a backfire, same for when you go to light it after the second fill, stand back.

I make smaller versions of this at work sometimes , with long thin tin cans to heat a chisel that is my waxing chisel, I hold colored hard wax to the hot chisel an can melt it in long runs, let it go half hard then shave the coloured wax flush with what ever I'm filling

It would be safe to try out side ,and if it works you could adapt to do at a bench later.
if it will hold 500ml of metho it should run for ? 30 minutes at a time.
Could be the 10 buck bender

cheers
Attachments
bending_pipe.jpg
bending_pipe.jpg (112.24 KiB) Viewed 20240 times

User avatar
auscab
Blackwood
Posts: 650
Joined: Wed Jan 12, 2011 1:12 am
Location: Melbourne Australia

Re: Side bending alternatives...

Post by auscab » Sat Oct 22, 2011 5:52 pm

PS.

The smaller versions I do at work dont have the rag in them, the holes in my can are 20 mm approximately above the bottom and I just fill to the holes with metho.

MattW
Myrtle
Posts: 72
Joined: Wed Apr 27, 2011 9:42 pm

Re: Side bending alternatives...

Post by MattW » Sun Oct 23, 2011 11:13 am

Insomnomaniac wrote:Ok, after some pretty major financial setbacks, I am FINALLY getting around to starting on my first uke...

Money is still very tight, so I'm trying to save some money where I can. Being a carpenter I have most of the tools I will need (or at least ways and means of improvising) but one thing which is throwing me a little is a side bending iron. I don't want to spend $250-300 (plus shipping) on a side bending iron which I may not end up using very much (straight away). Can anyone suggest a workable alternative that won't break the bank? I work at Bunnings, so anything I can source through there would be an advantage (staff discount and all...).

Help!

Hi

I may be able to send you something, do you have a small propane torch or similar means of heating a short pipe?

I can send you an aluminum cylinder with 4mm wall thickness approx 100mm in diameter and 300mm long. One end is cloesed off, it was a calibration gas cylinder, but is empty and has been drilled. You could mount it up similar to the examples shown by others above. PM me if your interested.

Where are you located for postage?
Cheers

Matt

Insomnomaniac
Myrtle
Posts: 80
Joined: Fri Oct 15, 2010 6:17 pm
Contact:

Re: Side bending alternatives...

Post by Insomnomaniac » Mon Oct 24, 2011 4:12 pm

Thanks for the tips, guys!

Cylinder is on its way from Matt, and I'll use a burner setup like Graham suggested to heat it. Looks like a pretty straightforward setup with some degree of adjustability temperature wise. Fingers crossed!
Ian

Carpenter turned Knifemaker, now tentatively trying Luthiery as yet another hobby on the list...

MattW
Myrtle
Posts: 72
Joined: Wed Apr 27, 2011 9:42 pm

Re: Side bending alternatives...

Post by MattW » Mon Oct 24, 2011 7:14 pm

No problem

Here's a pic of mine

Image


Image
Cheers

Matt

User avatar
graham mcdonald
Blackwood
Posts: 473
Joined: Thu Oct 25, 2007 11:57 am
Location: Canberra
Contact:

Re: Side bending alternatives...

Post by graham mcdonald » Mon Oct 24, 2011 9:03 pm

The general rule for heat is that water sprayed onto the heated pipe should bounce off in little drops, rather than stay on and then steam off. One thing to think about if you are going to be bending uke sides is that the pipe should be of a smaller diameter than the tightest bend in the sides, usually the waist or the upper bout. That is why I suggested a 50mm diameter pipe. Any scrap metal yard should find a length of 50mm pipe of some kind quite cheaply. It is also useful to mostly close the open end of the pipe off to keep the heat in. The pic I posted has a piece of copper sheet roughly bent to shape and pop-riveted in place.

Have fun

cheers

graham
Graham McDonald
http://www.mcdonaldstrings.com

User avatar
charangohabsburg
Blackwood
Posts: 1818
Joined: Sat Oct 16, 2010 1:25 am
Location: Switzerland

Re: Side bending alternatives...

Post by charangohabsburg » Mon Oct 24, 2011 11:47 pm

Sean Syman wrote:First time I bent sides, I steamed the wood in this, which would have cost us maybe $10 to put together;

Image
[...]
Impressive!

Some time ago I have seen something similar in this video:


youtu.be/

Its quite impressive too.
Breaking the sides does not seem to be an issue with this method, but I'm not sure how highly figured (flamed, curly, etc.) woods behave using steam.
Markus

To be stupid is like to be dead. Oneself will not be aware of it.
It's only the others who suffer.

Insomnomaniac
Myrtle
Posts: 80
Joined: Fri Oct 15, 2010 6:17 pm
Contact:

Re: Side bending alternatives...

Post by Insomnomaniac » Tue Oct 25, 2011 12:03 am

Thanks for the extra tips there Graham! I can probably find a narrower pipe at work somewhere, too. I could set up a 2-sided jig that way as well. Hmmm...
Ian

Carpenter turned Knifemaker, now tentatively trying Luthiery as yet another hobby on the list...

MBP
Blackwood
Posts: 180
Joined: Sat Aug 20, 2011 3:48 pm

Re: Side bending alternatives...

Post by MBP » Tue Oct 25, 2011 2:11 am

Some copper pipe and a 100 watt light globe work great.

Just wire up a standard light to a cut extention cord. Silver solder an end and cut small tabs for screwing onto a wood block.'

Post Reply

Who is online

Users browsing this forum: Google and 24 guests