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Just a question, more out of curiosity. I'm sometimes amazed (and frustrated) at how thick some of the ready cut Back/Sides come from some of the suppliers. I've even had Indian Rosewood at near 6 mm's thick! That's a lot of waste when you plane it all down to 2.5 mm's and less for sides. So my question is for those who resaw their own timber, tropical or homegrown. How thin can (or dare) you resaw to safely have enough to end up with smooth finished material? Obviously the quality of the machine, blade and set up will be a huge factor.

I try to get 12.5 max and when everything is cutting good I go for .10 to .11 when I know I will thin to .08 - like you said - depends on the type of finish you get from your blade. I get a pretty good finish from my blade and a fairly straight cut. The issue with cutting thin is that if the blade begins to wander a little - you could slice a piece too thin and mess up the surface for the next cut.
I just blew (trashed) through some nice cedar like that and my cut was not too thin - my blade did not like the cedar, but loves the harder woods.

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It's this new idea from recent decades that everyone gets a participation award. - MUX

With my setup I usually aim for 3/16" I know that is very thick but better than trying for thinner and having to much blade drift. Maybe I should spend some money and go for a better setup.

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Joe Beaver
Maker of Sawdust

I go for 1/8 - 3/16in but I don't have a very good saw. Even if I did I'm not sure I would want to go any thinner then that just in case. It might seem wasteful to cut thicker but then thing of the waste when you blow a cut.

I go from 0.125 to about 0.150.

I've cut thinner but have also wasted a fair amount of wood because it wound up too thin after sanding out the saw marks.

Kevin Looker

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I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

I end up losing about 1/16" per cut, and not usually symmetrical about the center of the cut. I've cut sides as thin as .08 to .09", but then they're taken down to ~ .06". With good conditions (sharp, clean blade and wood that's not difficult), I usually try to cut about .05" thicker than my target thickness, that gives me enough extra to be sure it's thick enough. With less than good conditions, I'll go thicker, maybe as much as .10" thicker. It usually comes down to how many useable slices can I get from the initial thickness.
I don't have an expensive saw, it's just a 14" Ridgid with a riser block, but I do keep it pretty well tuned. I use a 5/8" 3tpi Timberwolf blade for resaw.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon

Depends on the wood, the day, and how the saw/blade is doing. If it's for wood I'm going to sell I generally try for .16" off the saw for backs, .125" for sides which gets me .15 and .11-.12" finish sanded pieces respectively. For boards I'm building with I'll go thinner to maximize yield if I need to. This is for typical vertical grained lutherie tropical hardwoods... I make adjustments for grain orientation, density/stiffness, shrinkage, and moisture content for each individual board. If I didn't really know my saw, blade, and woods very well I'd probably want to add 20% to those dimensions until I did. I have a nice resaw and carbide blade.

All the wood I've ever purchased has clocked in at about 3/16th's and has been pretty rough, to me. It smooths out at about .150, which is perfect for jointing, rosetting, and sanding to final thickness.
I can see how sides might could be sawn a little thinner to start with, but I don't mind the extra security of slightly more thickness.

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Old growth, shmold growth!

Getting back to measurements that I understand...I will resaw instrument wood with a fresh blade only and set the cuts for 4mm. I don't like waste anymore than others, but as has been mentioned, the most wasteful cutting is when you have to trash all of your wood into the firebox because you screwed up big time.

6mm is overly generous to my mind.

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Expectation is the source of all misery; comparison the thief of joy.
http://redrivercanoe.ca/

4mm ~ 0.10", so we're pretty close on our minimum thickness.
6mm ~ 0.15" I agree that's generous.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon

I usually resaw to 4-4.5mm. After screwing up one too many times I/ve learn/t to err on the side of caution.

In the beginning of my re-sawing - I was trying for as thin as possible, to "Minimize waste".....

Then... The epiphany struck me that it was *MORE* wasteful to waste slices and perhaps an entire board to saw blade runout or a bit more taper than I expected....

and then - I decided to saw a bit thicker...

It takes a *LOT* of work and time to get the saw set up perfectly to minimize cut thickness and still have something useful.. to work out all the taper and barrel and all the rest... but Technique is just as important as the Saw setup... Push too hard, stop a bunch of times in the cut, uneven pressure this way or that way.... let your mind wander... That's a fine way to waste a pile of wood there too....

I decided that letting the sander eat a bit more wood was OK so long as I ended up with good slices...

Thanks

I have a 16" Makita resaw, on which I installed a 3 HP motor. I have owned it for 23 years, and I still occasionally have difficulty making a straight cut. Whoever said that resawing is probably the hardest skill to learn of any woodworking machine certainly has my vote.
I have cut about 6000 red spruce guitar tops, and resawn over 800 sets of Brazilian RW. The red spruce has mostly been cut green, using a very coarse blade. Because of the surface finish, I usually try to cut at least 0.185" thick, but I am happy if I stay between 0.200" and 0.220". The dry hardwoods are cut with a much thinner blade with more teeth (smoother cut), so I feel fairly safe cutting backs around 0.175" and sides around 0.160".
I also mill local hardwoods from green, in two steps. The first step is to cut boards that are 1" to 2" thick, using the coarse blade. The wood is then air-dried for up to two years, after which it can be resawn with the finer blade. This eliminates the cupping that so often occurs when green hardwoods are cut thin to start with.
Once you ruin some expensive exotic woods by rendering them into peghead veneers, you learn to be a little cautious.

Most of the Indian RW sets are cut in India, and the surface finish can be pretty rough. The law in India is that raw rosewood for export must be 6mm thick or less. I am not surprised that some sets are very close to the 6mm limit.

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John