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I've started in on my fourth guitar, and my first cutaway, an SJ of the venetian variety. Yesterday I glued up the linings, and this morning I sanded the back linings down to meet the sides. I had the bass side closest to me, so it was blocked from view by the body mold. Focusing on even pressure as I did the sanding dish shuffle, I watched for the cutaway side to come down to meet the dish. After just a couple of minutes of sanding, I stood the mold on its side to inspect the edge I'd been sanding, and to my horror, saw that the bass side had already sanded down to the point where the linings go from straight to triangular. In other words, I took a good 3/16" off the bass side in a matter of a couple of minutes, while the treble side linings had just begun to come down flush to the sides...

So now I have a rather wedge shaped set of sides. My theory is that the greater surface area created by the cutaway prevented that side from wearing down at the same rate as the non-cutaway side.

What should I do? a) Leave the sides wedge shaped, and tell myself it'll be more comfortable to play that way, or b) sand the treble side down to the same thickness, yielding a shallower body overall, or c) admit defeat, scrap the whole thing, and take up macrame?

It's times like these that I question if I really "cut out" for guitar building, so to speak.

Any words of wisdom or encouragement would be greatly appreciated.

Ken

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Mountain Song Guitars www.mountainsongguitars.com

I don't know very much. But in thinking of your dilemma, I am wondering if you removed the kerfed linings form the 'too low side' and re-glued in taller linings that you can then sand down to match the side thickness of the treble side. Since you will be routing off the side for the binding/purfling you may be able to salvage it.

Good luck!

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Steve Walden
Aspiring Builder,
Bartlesville, OK

Did you pre-taper your sides like you would on a non-cutaway? If so, that could be your problem. On a Venetion with a domed back, the side gets narrower as you get to the horn but gets wider again as it goes into the cutaway. This can cause the lining to get sanded to a changing width but the sides aren't necessarily off, bass to treble. Did you measure?

On a venetion, I don't taper my cutaway side as much and I profile the the back before putting on lining to prevent that problem.

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http://www.chassonguitars.com

I'd leave the taper. Tell folks you planned it that way. At least it's tapered the right way!

Don't know that I'd even bother removing the linings on that side, as long as enough gluing surface area is left. But, then again, I'm no pro. Just my opinion. Based on the fact that my current OM wound up with a taper, too. Intentional, of course.....

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Wes McMillian
Santo, TX
http://www.wesmcmillian.com

That's an interesting idea Walden. From what I understand, though, ideally there should be a thin skin of side left after routing the binding ledges, no?



Kent, I decided not to profile the sides ahead of time for that reason, though I did make templates directly from the body mold, which includes the cutaway. I just erred on the side of caution at the last minute. I did profile the sides once I glued in the neck and tail blocks, and glued the linings in 1/32" above the side profile.

Things were going so smoothly till now...

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Mountain Song Guitars www.mountainsongguitars.com

I'm inclined to agree with you. Since it is the back, it shouldn't affect the heel/block/fretboard/top plate/bridge relationship. You can be I'll be watching very carefully as I sand the top linings down, though.

Any acoustic/tonal issues I should be concerned with, if I leave the taper in there? What does crooked sound like?

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Mountain Song Guitars www.mountainsongguitars.com

The cutaway curls back toward the center of the body and then back towards the neck the profile is vastly different profile than a non cutaway side. The elevation of the rim at any given point perpendicular to the body centerline must be equal both sides of the centerline. because the cutaway reverses direction the standard side profile will not work and will cause you to either over sand the non cutaway side or cause a tilt in the dish depending on how you do the sanding process.

Steve (Walden) has an excellent idea! Use the kerfed linings to make up the difference if there indeed is any after you measure as Kent rightly suggested.

And you ARE cut out for guitar building Ken my friend. This stuff happens to us all even though not everyone is willing to post their trials and tribulations here. This is how we learn and what you have is something that can be fixed I am sure.

Right. Just to be clear, I only profiled the sides once the blocks were glued in, and I then profiled the sides in the sanding dish. I then glued in the linings. Up to that point the sides were money. The taper only occurred once I went to sand the linings down flush to the already profiled sides.



Hesh, thanks for the words of encouragement. I thought I'd gotten all my boneheaded screwups out of my system on the previous builds, but as I'm discovering, there's plenty more room for error when one introduces a cutaway into the equation.

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Mountain Song Guitars www.mountainsongguitars.com

This then confuses me a tad. I take it that you set your non profiled rim and block assembly in your dish and using a transfer compass, traced the intersection profile using the intersection of the rim to the dish? How did you account for the decline from butt to neck? (Back) how did you index the intersection plane at the points where the rim would not touch out on the dish? Which would be most of the rim in my thinking as the end blocks full rim height would rest on the dish and the rest of the rim would be clear.. I am not trying to be contrary here just trying to figure out how you did this. What kind of tool that you used to trace the profile? How you accounted for both the bridging effect of the full non profile rim over the dish as well as the depth change butt to neck?

I am sure I am missing something in the translation here but would seem to me that this process for tracing your profile would lead to a equal depth at both butt and neck unless you used a stand off shim at the butt.

The reason I am asking so much is to try to figure out why you ended up sanding deeper on one side than the other. If the profiles were equal heights on side to the other and the lining is glued in place the same height above the profiled rim all the way around then if the sanding dome is maintained at a perpendicular angel to the rim you should contact a given point both sides at the same time.
If you sand as I know some do by laying the sanding dish on the bench and moving the rim back and forth in line with a given centerline of the dish there is the possibility of applying to much pressure to on side of the rim assembly.

There are al lot of different ways to use the sanding dish. I use a rod and bushing adapter for my dish. The rod is set in a fixture that aligns with the centerline of the rim at a given axis point that sets the angle from butt to neck. The dish has a bushing that matches up with the rod or axel and contacts the both the neck block and tail block at the same time. I rotate the sanding dish around this axel fixture till the lining is flush with rim and the bottom of the neck and but blocks are fully radiused. This axel and bushing does not allow the plane of the sanding dish to get out of square with the rim assembly.

Really what I am getting at is that if the profile is equal height and square one side to the other the only thing that can cause you to sand more from one side than the other is to allow the dish to get out of plane to the rim or vise versa.

I am not knocking your system, only trying to help you figure out where the problem originated at.

Water co. cut cable, so i'm on cell phone. Sorry for shorthand. I hand planed down to predetermined points on neck an tail blocks, then used dish to work sides down. I almost made a spindle for my dishes based on Lance's, but was impatient to get it done. Dumb mistake. I do think my screwup was caused by the greater cutaway-side lining to dish surface area, moreso than a difference in pressure, though that may have been a factor, too.
Thanks for your interest in my predicament, Michael.
Ken

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Mountain Song Guitars www.mountainsongguitars.com

I'm not a builder by any stretch of imagination, however, I would suggest that you *not* scrap the guitar and keep on going the way it's going. Who knows? It may turn out to be the best sounding instrument any of us have ever heard. That's why I admire these guys here so much-- they all know that the whole is greater than the sum of the parts. I started to take a different view on these things after I heard that upon introduction, the Les Paul and the Telecaster were referred to as "the log" and the "canoe paddle" by those who thought they just didn't look right.

Half a dozen posts above someone asked a very profound question, " What does crooked sound like? Maybe that explains all the strange noises coming out of my music room!............... Mikey

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The Biggest Little City, Nevada
www.hammondguitars.com
I love building guitars!