English wheel

[Stevie]

I think it's because you can target the heat accurately with a large "old fashioned" iron and that means greatly reduced distortion, but with a flame it inevitably spreads out and then you end up with an undulating top. With the domed pressing on the back that's less of a consideration because it will be much stiffer but still pertinent to some degree.

At one place I worked, the welding bench was topped with an additional 1/4" mild steel plate, in a half-hearted attempt to provide a flat plane reference of sorts, but over the years folks would lay the lit oxy-acetylene torch down on it while lining up parts for welding, and the 1/4" plate looked like The North Sea on a good day. That would be unavoidable if playing flame heat on a guitar with its much thinner sheet materials and then you would have to go about correcting it. No easy task and almost impossible to hide when the end finish is polished and electro-plated (unless you're Mr. Mike Lewis of course!)

The metal will seem to have a life and mind of its own TT, you'll do a bit and it'll move some place else while your gaze is focused elsewhere. That said, I know you'll be OK after a bit of practice. When and If you get it somewhere that suits you, you'll need a swager to put the flange around the edge. No swager? Make a bending tool by hack sawing a slot in the end of some steel bar and go around the edge bending bit by bit gently. That flange will probably need shrinking slightly but it's so little that you may get away with dressing it back against the line of the swage. Use a soft face or mallet to dress the mounting flange otherwise every hammer blow will stretch the material. Even though you'll need to coax the flange down flat, you'll be chasing even more ripples down if you use a hammer.

If I'm guilty of judging others by my own perceived shortcomings, it is because I have stood on the shoulders of giants and I don't like heights!

e&oe ...

[Pickers Ditch]

The other thing that you must remember is not only heat distortion which Stevie describes very well is that every time you deform sheet metal - put a bend in, roll it, twist it, hammer it, etc. - it stretches.

Us tin bashers (yes, I'm allowed to use that term as I'm a time served, fully indentured apprenticed sheet metal worker who gave it up when the apprenticeship was completed) were taught these things and it still seems like a black art to me.

There are booklets with tables listing the stretch factors for different metals, guages, folds, angles etc. but the only thing that seems to work is practise, practise, practise - just like playing slide guitar really.

....also beware of snips, guillotines and folders; they bite too.


My right index finger 55 years on - terrible nail growth, and the cuticle still splits and bleeds at the slightest opportunity.

[Michael Messer]

The soldering of a metal bodied resonator guitar is done from the outside. It could not be done any other way. Soldering in that way is a skilled job and the excess is wiped off with a damp cloth.

Shine On
Michael

[Stevie]

It is obviously done that way and to "make good" the joint it would no doubt be done from the outside even if it had been soldered on the inside first. It's entirely conceivable (but unlikely) that (for argument's sake) the inside of the back or the top could be soldered inside, but at the end of the day, like varnishing the floor boards in a room the last joint has to be from the outside so we all know how they must be put together don't we? Value engineering decrees no internal soldering of course (especially in rice bowl economies).

I imagine that wiping off the excess is a method approaching that of a lead wipe which is outside the scope of this thread but a spectacular skill nonetheless. I have a lead wipe on my "top hat" downstairs carsey downflush cistern down pipe. They all laughed at me when I restored / preserved it. Rolls Royce car doors used to be lead flashed on the outside, probably still are. It's a black art. It's a dying art- literally ...

I have a mangled RH "ring" finger nail PD, caused by an argument between a metal framed window transom light latch, and a floorboard chisel at Thames TV in Teddington. From memory, where I was working I had to fly downstairs, along a ground floor corridor lined with framed monochrome prints of faded stars and up at least one flight of steps to a rest room and precious running cold water, by which time the damage had permanently set in. As I ran along that corridor, I collided with Benny Hill who I knocked to the ground and endured a stream of abuse. I bet his picture's up on that wall now!

For me this is a great thread, but for most contributors I expect somewhat less so, and for that I apologise.



e&oe ...

[linkous]

This is how I make a cover plate, deuce (no English wheel needed):











All kind of designs:









And also hand rests:  

[Stevie]

That's lovely work linkous, especially the fretsaw work. I like your approach too. Reminds me of the sandbag technique. I assume that the fret saw work is performed after the basic shaping. How long does it take to arrive at that dished profile? Lovely handrests too. Definite thumbs-up.

e&oe ...

[Deleted]

Wow, impressive!
So you use a hammer to create the dome.
Thanks for the info
TT

[Deleted]

Stevie, when I was at school I wanted to do woodwork O level, but I was forced to do german. I vowed to do no work whatsoever for it in principle, and was rewarded with a 'unclassified'. I think I would have stuck with crafting, and I regret being forced out of it. But here I am, ready to take it on again
I have a little knowledge and fewer skills, so this thread (like many here) is like water to a sponge for me, and it should be of interest to anyone who loves guitars.
TT

[Stevie]

I went to a grammar school where anything manual, mechanical, practical and so on was discouraged. On the day I left, I was told by my form teacher that I would amount to nothing. Can you imagine any teacher telling one of the little varmints that these days? It's easy to get the impression that they're all told how wonderful they are and can do no wrong whatever they try. This has resulted in what I perceive as an "entitled" generation. I drifted into sheet metal work because Pa had his own company and I suggested to him that I might get a job at the local hospital as a porter. "No son of mine ..."! Well, unlike PD, I was pretty much self taught with no apprenticeship, and the old fella sent me off to college where I got my HND. That like the grammar school education was wasted too! Funny how things work out n'est ce pas?

I, I, I, Me, Me, Me. Enough already! MM is tearing his hair out ;<D

e&oe ...

[linkous]

Most of the work is sawing with the fretsaw, Stevie, and that is done before forming the dome. The following is making the wooden mold. Shaping the dome actually doesn't take that long, depends a bit on the material, I noticed that brass sheet (1mm thick) seems a bit tougher.


I work with two hammers, deuce, a rubber mallet (actually just the head) resting on the plate and a heavy hammer that I use to hit the rubber one as I move it around on the plate.

Here's one more:







To hide this..

[Deleted]

Brilliant!
Sorry, but can you post a pic of the fret saw and blades?
TT

[linkous]

Fretsaw is a Stanley, deuce, but it can be done with any other..




The saw blades I use are those from Proxxon (model 28113). But again, there are many other brands that are just as good, as long as they are suitable for cutting metal.


Whenever possible I use the jigsaw, such as with a had rest for example:



Keep in mind that building a (reso) guitar is not rocket science (contrary to what many may say here ..). Just like with so many skills (guitar playing, for example) it just has to exert some kind of addictive attraction to you. Then it will work.


Good luck!

[pete1951]

Here is a pic of a back I made (via the famous Rubber Press) you can see there is about 6mm of a lip that was soldered to the sides. 20 years on and it is still in one piece.
Pete

[Deleted]

Very grateful for your insights.
TT

[pete1951]

Apr 18, 2021 8:30:49 GMT linkous said:

I have also tried a dual-olian, but with 2 full size cones. I might try your method of cover plate making, without a cover plate it did not sound as good as I hoped but I should finish it sometime. Mike Lewis ( Fine Resophonics) did a few with the 6”- 9 1/2” setup maybe Michael M can tell us what they sounded like?
My bridge is cast is yours extruded aluminium?
very interesting work, maybe start some other threads about your guitars 
Pete

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