Back and sides thickness?

[wolfe]

Hello,

I am new to the forum, and also new to guitar building. I am just about to start construction on my first acoustic guitar.

The answer to this question may be on this forum somewhere, but I figured I'd ask anyway. What thickness do most builders prefer when it comes to backs and sides? A follow up question would be, what would you recommend if I don't have a thickness sander?

For my first build, I plan on using a beautiful set of quilted maple I recently purchased. The backs and sides are currently approximately 0.125".

Thank you.

[runamuck]

The first thing I would strongly recommend is that you not use quilted maple for your first guitar - especially without a thickness sander.

However, if you insist, a very, very sharp hand plane will do the job if you can set it up at a 50 degree angle. See if you can find someone with a thickness planer in your neck of the woods, though.

Somewhere in the area of .070 to.080 for the sides and .090 for the back but that really depends on the wood.

Oh, and then there's bending the sides; quilted maple can sometimes be challenging.

Get a set of plans for the type of instrument you want to build or get Cumpiano's book.

Jim McCarthy

[wolfe]

Originally Posted by runamuck

The first thing I would strongly recommend is that you not use quilted maple for your first guitar - especially without a thickness sander.

However, if you insist, a very, very sharp hand plane will do the job if you can set it up at a 50 degree angle. See if you can find someone with a thickness planer in your neck of the woods, though.

Somewhere in the area of .070 to.080 for the sides and .090 for the back but that really depends on the wood.

Oh, and then there's bending the sides; quilted maple can sometimes be challenging.

Get a set of plans for the type of instrument you want to build or get Cumpiano's book.

Jim McCarthy

Thank you for your response. I am not dead set on using quilted maple for my first build. Which type of wood would you recommend to use for a beginner?

I do not have a thickness sander, but I do have a thickness planer.

Thank you for the recommendations on the backs and sides thickness.

[martinedwards]

any figure in the wood makes life more challenging, both in planing and bending.

for a 1st attempt I'd go for plain mahogany, walnut or rosewood. several suppliers will do a pack of practice sides which might have pin holes etc so they aren't perfect for most folks but they're a cheap way to practice the bending process.

[runamuck]

Originally Posted by wolfe

Thank you for your response. I am not dead set on using quilted maple for my first build. Which type of wood would you recommend to use for a beginner?

I do not have a thickness sander, but I do have a thickness planer.

Thank you for the recommendations on the backs and sides thickness.

I'd suggest East Indian Rosewood. Contrary to Martin, I would not suggest Mahogany. My experience has been that some Mahogany bends quite easily and some of it can be really difficult and prone to fracture and ripple.

When I first started out, I had resawn Mahogany from the same board and I cracked 3 sides in a row. Obviously, my lack of experience bending had a lot to do with that but in bending other Mahogany sides over the years I discovered it to be unpredictable.

It's very risky trying to thickness plane down to the thin dimensions you'll be needing and that's why people use thickness sanders or a hand plane. If my planer is perfectly tuned up with freshly sharpened blades and I'm using a slave board, I feel comfortable going down to .125 or so if the wood is
unfigured and there's no run-out. But since I have a thickness sander I never risk even that anymore and stop planing at about .20.

Jim McCarthy

[wolfe]

It looks like I may need to make some more tool investments! A thickness sander sounds like a must have. I did use a slave board to plane down to .125 and it was pretty scary. I wouldn't want to try any thinner than that.

Thanks for the advise on recommended first time bending species.

Does anyone have experience bending cocobolo?

[mmapags]

http://www.kitguitarsforum.com/board....php?f=4&t=777

Take a look at this thread on the Kit Guitar Forum. It shows a way to build a relatively inexpensive manual thickness sander. To buy a power one is very expensive. This is a nice option thicknessing your first couple of guitars. BTW, I don't know that I'd ever use a hand plane to thickness a back. Just don't see how you could get a uniform thickness that way.

[wolfe]

Originally Posted by mmapags

http://www.kitguitarsforum.com/board....php?f=4&t=777

Take a look at this thread on the Kit Guitar Forum. It shows a way to build a relatively inexpensive manual thickness sander. To buy a power one is very expensive. This is a nice option thicknessing your first couple of guitars. BTW, I don't know that I'd ever use a hand plane to thickness a back. Just don't see how you could get a uniform thickness that way.

Thanks for the link! I may try this for my first few projects. That's an innovative and inexpensive solution!

[arie]

For the first back, sides, and top I used a plane and a scraper. Not easy and hard on the hands. For our next pieces I bought a small milling machine and a Wagner Safe-T-Plane. I also bought a couple of Bosch power sanders.

For the next guitar I think I'll rough mill the tops/backs/and sides with the Safe-T-Plane, semi-finish with the sanders, and then final dimensioning will happen with a scraper. I actually don't have the room for a thickness sander nor a way to deal with all the dust and noise just yet.

As to the actual thickness of the wood it really depends on what you want out of the guitar and how responsive you want it to be. Is it a small guitar or a large one? is your back going to be a diffuser or a reflector? what is the guitars energy budget? how are you bracing it? etc... simply quoting numbers to strive for doesn't really take into account the characteristics of a particular species of wood nor the stiffness of the wood, or any other organic properties or construction techniques -all of which influence final dimensioning.

Although I'm not a seasoned builder with a large body of work under my belt by any means, I would urge you to avoid the "exotics" for your first couple if instruments. IMO plain straight grained, Mahogany, EIR, and Spruce are proven to give good results for beginners and easy success is a great confidence builder towards working with the more challenging species of woods.

[wolfe]

Originally Posted by arie

For the first back, sides, and top I used a plane and a scraper. Not easy and hard on the hands. For our next pieces I bought a small milling machine and a Wagner Safe-T-Plane. I also bought a couple of Bosch power sanders.

For the next guitar I think I'll rough mill the tops/backs/and sides with the Safe-T-Plane, semi-finish with the sanders, and then final dimensioning will happen with a scraper. I actually don't have the room for a thickness sander nor a way to deal with all the dust and noise just yet.

As to the actual thickness of the wood it really depends on what you want out of the guitar and how responsive you want it to be. Is it a small guitar or a large one? is your back going to be a diffuser or a reflector? what is the guitars energy budget? how are you bracing it? etc... simply quoting numbers to strive for doesn't really take into account the characteristics of a particular species of wood nor the stiffness of the wood, or any other organic properties or construction techniques -all of which influence final dimensioning.

Although I'm not a seasoned builder with a large body of work under my belt by any means, I would urge you to avoid the "exotics" for your first couple if instruments. IMO plain straight grained, Mahogany, EIR, and Spruce are proven to give good results for beginners and easy success is a great confidence builder towards working with the more challenging species of woods.

Thank you for sharing your experiences. As far as bracing, & diffuser / reflector characteristics, I haven't even begun to consider these things yet. I obviously have a lot to learn. I guess I need to figure out which species I will try first.