Side Bending

[Darryl]

Hi All,

I've started my first resonator project and would like some advice on bending the sides.

The Gary Dusina process I'm loosely following advises using two 0.015" shim stock strips to sandwich the side material (in my case, solid mahogany). I can see how these pieces would help to form the wood into a fluid bend. 

Long story short, the supplier I'd ordered the steel from has let me down, so I hoped one of you might know where (preferably in the UK) I can get something suitable - or if there are alternatives I can consider. 

I know I can pick up a sheet of aluminium at my local DIY store, but fear this might not offer the same 'flexing' characteristics necessary.

Grateful for your advice.

Darryl

[Stevie]

Pure aluminium is extraordinarily flexible and pretty rare too. I imagine you're suggesting some form of dural alloy?

e&oe ...

[Darryl]

Hi Stevie,

I only saw the sheet in passing whilst wandering around B&Q in a daze. The description online is "Silver effect Anodised Aluminium Smooth Sheet, (H)1000mm (W)500mm (T)0.5mm" - they keep it in the building materials section.

I suspect that this would bend easily enough and do the job, but it won't be as springy as shim steel so I'm concerned it wouldn't shape the wood properly.

Thanks,

[pete1951]

Some Nationals ( or rather fiddle edge Dobros) were made of aluminium , they are considered to sound inferior to wood ,brass or steel. Welding aluminium is also a much more skilled job than soldering, which on brass is fairly easy.
Pete

I have made ( with the help of an aircraft engineer) a metal body reso but can’t remember how we bent the sides( this was 30 years ago) will check with him soon.

[linkous]

I think Darryl is looking for this, Pete: link


You can also visit a painting, carpet or wallpaper store, darryl: link 2

[Darryl]

That's brilliant, thanks. The StewMac tool is, obviously, the right item, but I'd need two and would get stung for VAT+ admin fees to import it, so that carpet fitting tool looks perfect. I can (hopefully) jigsaw the 2m version in half and have the two pieces I need.

Thanks, Linkous - and thanks Pete and Stevie for your help as well.

[pete1951]

Ha! So it’s not FOR the sides! It’s just that I couldn’t believe anyone would be using Solid wood for a reso! I might start a thread about it ( not)
Pete.

I should have gone to Specsavers

[Darryl]

Pete - Yeah, tell me about it. This has been more contentious than when Dylan 'went electric'! 

[Stevie]

Pete, as a one-off, to have had any much chance of a finish worth looking at you would have used bending rollers. In that instance of a guitar body, bending first one way then the other then back again and then back yet again for one side alone is very tricky to get right. Some of the bends have variable radii. I would have really struggled big time. It hinges precariously on exactly where each bend starts and trying to gauge that within the rollers by eye, and knowing what you can get away with tweaking it to fit exactly.

The anodised aluminium alloy sheet does not lend itself to welding- mild steel has a lot going for it in this application whether soldered of welded (although there's much less distortion with soldering) as does brass. anodise stinks when it's being burned or ground. Better to find untreated material and apply a surface treatment after fabrication. I'd twist Bonzo's arm!

e&oe ...