000/OM Build thread. Ba-Zillion questions

[ClaptonWannabe2]

Originally Posted by JonWint

I read Cumpiano and 3 or 4 others also.

Your best chance and quickest way of completing a guitar is if you build from a kit. In that case, the StewMac instructions will be almost entirely what you need to get it done.

Looking to lmi. O'Brien guitar kit. There's a bit of tweaking you can do with the kits. Though his kit suggests spruce and EIR. It's my preference too.

[charles Tauber]

Originally Posted by ClaptonWannabe2

What creates the taper to the sides themselves.

You do, or the kit comes already pre-contoured.

There are several different geometries one can use for the curvature of the back: cylindrical, spherical or something in-between. First, one decides what curvature the back is going to be. Then one decides how deep the sides are going to be at heel and an butt. The curvature of the back, in conjunction with the depth at heel and butt - and the shape of the guitar - determines the shape of the sides.

Latterally, the further you go from the centreline of the guitar, the shallower the sides. With the "S" curve of the guitar shape and the domed back, the sides are relatively thinner at upper and lower bouts. Superimpose a taper t the depth of the sides - from butt to heel - and you have an interesting contour for the sides.

Essentially, once you know what geometry you want, you can trace that onto the assembled sides, then chisel, plane and/or sand to the markings. There are different method for marking the sides based, in part, on the curvature of the back you are using and your method of building.

[ClaptonWannabe2]

Originally Posted by charles Tauber

You do, or the kit comes already pre-contoured.

There are several different geometries one can use for the curvature of the back: cylindrical, spherical or something in-between. First, one decides what curvature the back is going to be. Then one decides how deep the sides are going to be at heel and an butt. The curvature of the back, in conjunction with the depth at heel and butt - and the shape of the guitar - determines the shape of the sides.

Latterally, the further you go from the centreline of the guitar, the shallower the sides. With the "S" curve of the guitar shape and the domed back, the sides are relatively thinner at upper and lower bouts. Superimpose a taper t the depth of the sides - from butt to heel - and you have an interesting contour for the sides.

Essentially, once you know what geometry you want, you can trace that onto the assembled sides, then chisel, plane and/or sand to the markings. There are different method for marking the sides based, in part, on the curvature of the back you are using and your method of building.

I foolishly thought radiusing achieved this with sanding in a radius dish? Radius is only for the bottom and top, the curves of the side edges are what gets you from waist to heel and butt symmetrically and artistically?

[runamuck]

I'd suggest making all the jigs yourself - except a radius dish. I made one and, oh god! The dust! What a mess. It's worth spending the $80
-100.

[charles Tauber]

Originally Posted by ClaptonWannabe2

I foolishly thought radiusing achieved this with sanding in a radius dish? Radius is only for the bottom and top, the curves of the side edges are what gets you from waist to heel and butt symmetrically and artistically?

One method is to use radius dishes. Still, if you started out with a uniform width side, you'd be doing a LOT of sanding to get the contour you want. It's much quicker and easier to know what shape you want to end up with and then trim the sides before bending (e.g. on a bandsaw) or after assembling the sides, using chisel, plane, coping saw and sanding. Then sanding is to finalize the sides' gluing surfaces, rather than primary shaping.

If one has a machine-powered rotating sanding dish, you could power sand the sides to contour.

Look carefully at a guitar side, or, better yet, take a piece of paper and trace the contour of the side onto the paper, then look at the odd shape of the side.

[Bruce Sexauer]

For the first 15 years of my lutherie career I used simple clamping cauls to glue my braces to my backs and a hand plane to form my sides to receive the back. That’s about 75 guitars and they work as well as any others. There are many ways to handle every task we do, and the key is to throw your self into the process and solve the problems as they come up. Not everyone is cut out for the work.

[redir]

I don't use radius dishes but if I did I would just buy one. Some things are just not worth it in terms of time, time is money after all. That and the fact that MDF seems to be the material of choice and as someone already mentioned the dust in making one would be outrageous.

I'm still using clamps for bracing too. I guess everyone is using Go-Bars now but I just don't feel like making the change. If I was just starign off though I probably would.

[ClaptonWannabe2]

Who else sells radiused bars for brace shaping?

Martin I believe, and they are sold through Blues CreeK?

Anybody else?

[charles Tauber]

Originally Posted by ClaptonWannabe2

Who else sells radiused bars for brace shaping?

I don't know, but they are easy enough to make.

It's also easy enough to radius a brace using a hand plane or even sandpaper glued to a builder's level. Another approach is a jig attached to a disk sander - I used to do that. Another approach, one that I use now, is to make a simple clamping jig that holds all four back braces while having "tracks" on each side for the hand plane to run back and forth in. When the plane in the arched tracks stops cutting, your brace is done. And lots of other methods.

[John Arnold]

I don't use radius dishes. I use 1 1/2" wide cauls cut from 2X4's. The cauls are about 1/2" thick at the thinnest point. I have two for the X-braces (30 foot radius, basically). Those two have an unglued sloppy cross-lap joint so the crossing angle can be varied. That allows me to glue both X-braces at once. I use flat tone bars and finger braces, so those are glued flat along with the bridgeplate. That is my second stage of top brace gluing. In the third and final stage, I glue the upper transverse brace and the soundhole braces. The upper transverse brace has a 50 foot radius, so I use a separate caul for that.
For back braces, I have four cauls (15 foot radius) that were rough bandsawn. I lay a slat of basswood (5/32" thick by 1" wide) on each of those to even out the curve.
Before I built my go-bar deck, I would use these flexible slats and deep throat clamps to glue braces. Worked fine.

[ClaptonWannabe2]

Thoughts on tabletop bandsaws? My space (and budget but more space) will never allow for a true large shop bandsaw. What are the thoughts on table top bandsaws and drill presses?

As for the drill press, am I better off with a mount for a hand drill than a dedicated drill press?

[charles Tauber]

Originally Posted by ClaptonWannabe2

Thoughts on tabletop bandsaws? My space (and budget but more space) will never allow for a true large shop bandsaw. What are the thoughts on table top bandsaws and drill presses?

As for the drill press, am I better off with a mount for a hand drill than a dedicated drill press?

Perhaps, you are getting ahead of yourself. It would probably make sense to first make a guitar or two before investing in a lot of specialized jigs and fixtures and woodworking machinery. You might find that guitar making isn't what you thought it was or isn't "your thing".

To answer your question directly, it is entirely possible to make a high-quality guitar using only a relatively small number of hand tools. Certainly, machinery and specialized tooling can make it easier and faster, but aren't essential.

My bandsaw is probably the machine I most use. A drill press can be used for a wide variety of tasks, beyond simply drilling holes. In both, the throat depth and depth of cut/quill travel can be limiting factors on some operations. For example, if you want to cut out a guitar top on a bandsaw, you'll need a throat depth of at least half the width of the guitar. Not a problem for full size machines, but might be a factor in some desktop bandsaws.

It also depends upon what you want the bandsaw to do. If you are going to use it to resaw wood into smaller pieces (e.g. necks, braces, bindings...) you'll want a bandsaw that takes at least a 1/2" blade, preferably wider. The thickness of the wood that you can resaw is limited by the depth of cut of the machine and the machine's power. Before investing in a bandsaw decide what you want to be able to do with it.

[mirwa]

Originally Posted by charles Tauber

If one has a machine-powered rotating sanding dish, you could power sand the sides to contour.

This is my unit, all foot powered and variable speed, interchangeable radius dishes that clip on to the aluminium drive plate

Steve

[Rodger Knox]

Originally Posted by John Arnold

I don't use radius dishes. I use 1 1/2" wide cauls cut from 2X4's. The cauls are about 1/2" thick at the thinnest point. I have two for the X-braces (30 foot radius, basically). Those two have an unglued sloppy cross-lap joint so the crossing angle can be varied. That allows me to glue both X-braces at once. I use flat tone bars and finger braces, so those are glued flat along with the bridgeplate. That is my second stage of top brace gluing. In the third and final stage, I glue the upper transverse brace and the soundhole braces. The upper transverse brace has a 50 foot radius, so I use a separate caul for that.
For back braces, I have four cauls (15 foot radius) that were rough bandsawn. I lay a slat of basswood (5/32" thick by 1" wide) on each of those to even out the curve.
Before I built my go-bar deck, I would use these flexible slats and deep throat clamps to glue braces. Worked fine.

Same here. Different numbers, same technique. I'm still using clamps.

[phavriluk]

Cumpiano's was the first guitar building book I bought. I thought the book gave a really good description of building a Cumpiano guitar, but of limited use for executing what we now understand to be 'normal' guitars. Like the ink spent on making truss rods. Why?

Like in setting necks, mixing advice causes no end of confusion. Mixing Cumpiano with other authors and their books got my head spinning.

One book that I haven't seen praised is Brian Forbes' Acoustic Guitar Making(how to make tools, templates and jigs). It offers encouragement to get hands on and demystifies a whole bunch of stuff that commercial peddlers of tooling and jigs want to be required shop equipment. I don't much need left-handed screwdrivers.