side thickness

[thistle3585]

Well, I think I may have over done it thickness sanding some sides. One got down to .047 and the others are .070. I think that I tried to take too much off in one pass so the drum on my spindle sander heated up and expanded, thus making the sides thinner as I progressed through a couple sides.
I'm going to use these to practice bending and maybe to make a hollow electric or something where I can laminate them.
How thin can you get away with and still have confidence in their structural integrity?

[sunburst]

Don't know.
It depends on how accurate the bends are, and how much scraping or sanding will be done later. I don't think I would want to use sides thinner than about .060", but they might work fine. I've seen some mandolins with surprisingly thin sides, the result of a lot of sanding, I think. If they don't get hit by something, I guess they'll be alright.

[junksuph]

My first mandolin actually has spots,(hidden), where the back side of the kerfed lining is showing due to sanding and not paying attention. I insisted on completing the build, and today, it's my favorite mandolin. It's a real belly tickler and louder than all get-out. There are areas where the sides are paper thin, but not in a critical structural area. The mandolin is used hard every day and no signs of collapse.

[Dale Ludewig]

I don't know either how thin you can get away with. .080, as been mentioned, is common among a number of builders. A good compromise. My concern with getting so thin isn't that things are okay now, but if you're going to bind the instrument, there's going to be more abrasion/ scraping on the sides and they're going to get even thinner.

[Antlurz]

Plus, if the bends aren't almost exactly correct once glued in place, you will need to sand even more to get the shape right. You'd be on the ragged edge from here on out unless everything goes exactly where it is supposed to, and no problems come up later.

Ron

[Bill Halsey]

I made this in ~1977 as a bit of an experiment, with hard maple ribs very little thicker than a violin -- approx. 1.1 mm, as I recall. Strung with guy wire & fire tower cable, it's been my main pelter and has survived decades of brutal performance. The only problem encountered has been its owner's limitation as a performer. http://www.mandolincafe.net/iB_html/non-cgi/emoticons/laugh.gif

[Darryl Wolfe]

Gibson Catalog N (late 1923) flowerizes the construction of the rim assembly stating it being "less than one tenth inch thick when finished for sensitive...". #This "seems" to imply a rough state of 0.100 finished out to something less. #My experience indicates that they did considerable final shaping of the rim set after it was glued up.

[billt]

Why don't you bend some quartersawn pieces maybe .040" and laminate it to the thin sections? #Gavin Baird laminates all his sides this way, as I understand. #Many prominent guitar builders do also...just a suggestion.

[thistle3585]

Thanks to everyone for the feedback. I appreciate it. More than anything, it gave me a chance to realize that I probably should scrap this set of sides and make some new ones. There really isn't any need to take the risk if it isn't necessary. I'm just going to practice bending with them and maybe use them around a plywood frame for a semi hollow electric. I'm going to target a finish thickness of .080 on the next set. I did not think of the amount of material lost in the final sanding process, so I learned a lot more than I had thought. Thanks again.

[mandoJeremy]

Not to sidetrack this but Bill, that is a wonderful looking mandolin there! I love the color and the craftmanship looks great. Do you have any more pics of it you could post?