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I have had some trouble profiling sides using a radius dish. Last set I was happily grinding away and when finished had 3/8 difference in height on the lower bouts. Tonight I decided to use an old trim carpentry trick and scribe a line around the circumference of the back using a 15' dish and a 25' on the top. I was amazed at the amount of material you remove from the ends/sides to achieve your spherical shape. I trimmed the end blocks just proud of the line with my table saw and planed the rest. I'm planning on gluing my kerfed linings just proud of the sides minimizing "wheel time" Other than getting a perfect radius on the end blocks I can do a much cleaner job with my little Lie Nielsen plane.
Any comments/thoughts/critiques TIA

One standard technique is to level up the sides in the mould (if you use one) and chock them to your preferred front/back taper as the mould/sides sit in a dish. Scribe around with a pencil stuck through a bit of wood. Plane (block plane, spoke shave) close to the line. Glue in the linings, level to the line with said plane/spokeshave and then (and only then) use the dish to sand on the bevel angle. Should take no more than ~ 2 minutes of sanding to get a perfect fit, and you have a pencil line to reference to so you avoid accidental "tilts". Same for the top edge (or vice versa if you started with the top). I think this is largely what you ended up doing.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

Yes thats the plan. I've installed cabinets and millwork for my dad for years and your always scribing to a floor/wall etc. I don't see any difference in fitting a set of sides. Thanks.

If doing the radius dish method without a rotating dish I work with the body in the mold and the dish clamped to the bench. I keep rotating where I hold the body 90 degrees every time I check the progress. It seems we naturally exert pressure more on one side than the opposite so I just keep changing where I hold the body. By doing this I am able to keep the body sides very close to equal.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

I scribe, plane, then finish up with the dish. Like Trevor said, it only takes minutes to get the final sanding bit done.

I've been there. I'm really attracted to the setups I see where people stick the dish over a dowel and rotate:

http://www.frets.com/FretsPages/Features/JT2000/JT2000Views/jt77.jpg

http://www.frets.com/FretsPages/Features/JT2000/JT2000Views/jt78.jpg

But I'm not set up for that. I keep the rims in the mold and rotate the mold. So now I'll do 15 strokes, flip the mold around 180 degrees, 15 more strokes. So if I had the neck side of the mold in my right hand, I'll do 15 strokes, flip it 180 degrees so the neck side's in my left, 15 more strokes. It keeps me even because I just naturally put more pressure on one side than the other.

More or less, just like Fred.