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Kevs-the-name
02-22-2016, 07:10 AM
I see lots of people asking “what thickness should xxx be”

I am trying to find out how the thickness (or more to the point the thin-ness) affects a ukulele build.

I have some very nice Utile mahogany. I have made a top and back that are around 1.8mm at the moment (will be sanded) but I managed to snap the original sides when bending. All I have left to match up is a very thin 1.1mm - 1.2mm sheet.
Would you use it for the sides? or is it too thin. otherwise ill have to scrap the idea... (in which case Im not sure what to do with the plates) any ideas please?
thank you

Michael Smith
02-22-2016, 07:24 AM
That is pretty thin but you could always add a veneer on the inside.

DennisK
02-22-2016, 07:40 AM
It would certainly be fine if you use side braces than extend past the edge of the linings (so there's no weak point where they meet). Or as Michael says, glue a veneer. Shallower box depth is another option to reduce the necessary side stiffness. Or depending on how stiff it feels, you might be fine at normal depth without any reinforcement, provided you don't lose much thickness in the various sanding steps.

Allen
02-22-2016, 08:50 AM
Double sides.

Find something else and veneer them. A friend of mine that is a hobby builder makes all his sides with 2 veneers. They hold their shape off the form perfectly, and are very stiff.

Rob-C
02-22-2016, 09:14 AM
Utile is pretty cheap - enough for two and a bit soprano ukes is going for £20 off ebay. Why not get some more?

Kevs-the-name
02-22-2016, 12:29 PM
Utile is pretty cheap - enough for two and a bit soprano ukes is going for £20 off ebay. Why not get some more?

I partly agree with you Rob, the problem is matching up.
The top and back are the same. I'm concerned that different sides will be, well, different!
The thin wood I have is an exact match.

Sorry to be stupid, but how do I 'double' or 'vaneer' the sides?

Pete Howlett
02-22-2016, 12:39 PM
Kevin
When bending mahogany you need to have the iron very hot, almost scorching hot and the sides about 1.65mm. Abandon your project - matching is too much of a headache and I should know, I spent an hour this morning going through piles of koa to match up some orphans. I'll send you some wood that will bend easily, properly thicknessed for top back and sides. Practice on this before you have a go at that Cuban I sent you. If you have cracked the Cuban stuff I'll send you another set - just let me know. When things start to go bad, that's the time to stop and judging by your post you are already half way down the road to ruin!

Michael N.
02-22-2016, 12:50 PM
Try bending it, see what the result is. If it distorts or corrugates too much, bin it. If it bends nice and evenly you can also add reinforcing strips across the width, on the inside. Some guitar makers do that anyway. There are a number of Torres guitars with sides as thin as that, some even thinner. Of course the sides on those are much wider than on a uke. Somehow they've managed to survive almost 150 years and of course some are still being played.

Pete Howlett
02-22-2016, 01:01 PM
Some modern Martin guitars have sides at 1.2mm!

Kevs-the-name
02-22-2016, 11:58 PM
Kevin
Abandon your project - When things start to go bad, that's the time to stop and judging by your post you are already half way down the road to ruin!

Thank you Pete. This is the kind of advice that I need!

I guess trying to rectify stuff at my level of building experience is just not worth it!! (Although good to learn!)
I'll get the 'easy' tasks right before trying expert methods!

I WILL learn to bend ha ha!

Thank you ALL for taking the time to advise. I appreciate your help no end...
It's all a learning process!