Bending wood the new/old way

[ErnieM]

Hi all,

The question I'm asked the most by people seeing my harpsichords is "How did you bend the wood for the case?" As I described in the 'Harpsichord Project' I laminate the bent section of the case.
A friend and fellow builder, Kevin Fryer, uses a totally different bending system that I thought would be interesting for some of you. This video shows Kevin bending a poplar board about 6' long x 10" wide x 5/8" thick.

http://www.youtube.com/watch?v=gsiNSEAew2o

Ernie

 

[Joe Scharle]

I've noticed violin makers using the same technique, on a much smaller scale!
Bet you won't find that heater at your local Harbor Freight!

 

[Sealeveler]

Thanks for the link,interesting.Tony

 

[Trent Mason]

Thanks for sharing Ernie. That's an interesting technique using that bending iron. :eusa_thin

 

[ErnieM]

I've noticed violin makers using the same technique, on a much smaller scale!
Bet you won't find that heater at your local Harbor Freight!

No, but I think they have one at the BORG - and use it on all the wood before putting them on the racks for sale.:rotflm:
Ernie

 

[CarvedTones]

I've noticed violin makers using the same technique, on a much smaller scale!
Bet you won't find that heater at your local Harbor Freight!

When I did some bent side string instruments, I used this method:

http://www.scavm.com/awfribs.htm

Fits my budget pretty well. :gar-Bi
There is an interesting NA bow making technique involving burying the coals of a fire, wetting the dirt over it and using heated logs that were soaked and then heated over the fire before the coals were buried. There are two short logs in three pieces - one is split lengthwise before soaking and heating. The split pieces are positioned flat side down over the buried coals to cradle the third one. The recurved end of bows are bent by slipping the end between the logs and prying up the cradled log and applying a little foot pressure to push the log back down. Water is poured over the logs every few minutes.

Ernie,

Do you have a dedicated bending iron like the one in the video?

 

[ErnieM]

When I did some bent side string instruments, I used this method:

http://www.scavm.com/awfribs.htm

Fits my budget pretty well. :gar-Bi
There is an interesting NA bow making technique involving burying the coals of a fire, wetting the dirt over it and using heated logs that were soaked and then heated over the fire before the coals were buried. There are two short logs in three pieces - one is split lengthwise before soaking and heating. The split pieces are positioned flat side down over the buried coals to cradle the third one. The recurved end of bows are bent by slipping the end between the logs and prying up the cradled log and applying a little foot pressure to push the log back down. Water is poured over the logs every few minutes.

Ernie,

Do you have a dedicated bending iron like the one in the video?

Andy

Thanks for the link - very interesting. No, I don't have a bending iron in the shop - I wish I had room for one. Kevin makes many more instruments per year than I do and his shop is huge. You can tour his shop here.

Using the bending iron seems more precise (and certainly quicker) than the laminating method I use. At the very least, it gives you more control over the amount of the bend. Lamination works well though - especially when you've used your laminating form for a while and learn to adjust the thickness of the bending plys to achieve a good match with your blueprint. Still, the bending iron is very tempting. Maybe if I can talk my wife into putting my tablesaw in the living room.:rotflm:
Ernie

 

[Glennbear]

Maybe if I can talk my wife into putting my tablesaw in the living room.:rotflm:

I cannot help but feel the resident harpischord painting artist would not be real keen on that idea.

:gar-La;

 

[CarvedTones]

I am curious about whether it makes much difference about which side you heat on a board that thick. That was (and probably still is; just haven't frequented a luthier board lately) a subject that came up for debate from time to time. With most string instruments, the wood is so thin you really couldn't heat one side without pretty much heating it through, but with a board as thick as he uses in the video, I would think it might make a difference. A lot of pro builders use a heat blanket that warms up the whole thing and their jig and slow pressure.

 

[ErnieM]

I am curious about whether it makes much difference about which side you heat on a board that thick. That was (and probably still is; just haven't frequented a luthier board lately) a subject that came up for debate from time to time. With most string instruments, the wood is so thin you really couldn't heat one side without pretty much heating it through, but with a board as thick as he uses in the video, I would think it might make a difference. A lot of pro builders use a heat blanket that warms up the whole thing and their jig and slow pressure.

I doubt that it would matter. That said, it's a rare board that's perfectly straight to begin with. If the board is even slightly cupped, I would put the concave side onto the bending iron and bend the wood in the same direction as it seems to want to go.

Glenn: You got that right!

Ernie