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Kit Dimensions

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Total Posts: 190
Kind of curious, StewMac doesn't seem to list the thickness of their sides, backs and tops, nor does Martin.
According to LMI their sides and backs appear to be .120-.140 respectively but they don't seem to list top specs either or I'm missing it somehow..
What about this...does anyone have these specs?

May 08, 10 | 9:59 am
Ken Cierp

Total Topics: 58
Total Posts: 2262
I can tell you this --

Processed rough materials can and do come into our shop as much as twice the final thickness.

And every single kit that KMG packages varies widely in thickness dimensions based on the type of wood, shape of the instrument (cutaway sides are pretty thin) and most importantly tap tone of the soundboards as well as flex of the back plates so the contour does not introduce stress in the assembly.


Kenneth Michael Guitars est. 1978

May 08, 10 | 1:21 pm
blues creek guitars Authorized Martin Repair Ctr

Total Topics: 52
Total Posts: 1011
There isn't one answer as you have to base the final size to what that particular piece of wood tells you. I agree with Ken , you can't rely on what you have in a kit it be sure it is at final thickness.
Bracing size , type and style all come into play. In most cases a top can be as light as .090 and as heavy as .125 . I have seen sides as thin as .060 and as heavy as .100. Same with backs.
Most production guitars are overbuilt for warranty issues . We at Blues Creek Guitars send the kits out about .005 heavy to allow you some final sanding.
On Sitka , I average about .105 red spruce .100 Sides .085 to .095 should be fine and .100 to .110 on the back. You should be ok with this

John Hall
Blues Creek Guitars Inc.
Authorized CF Martin Repair Center

May 08, 10 | 2:20 pm

Total Topics: 21
Total Posts: 190
Thanks Guy's for your replies.
Of course you guy's have the equipment and ability to re size components to a thickness much closer to the required needs of the whole where plain O'l Beginners like us are generally pretty much hug out to dry by some of the suppliers like Stew Mac...or LMI..that's why I'm a little shy of their products. From what little I've learned here.."One size does not fit all!" and "Cookie Cutter" Products are not ALWAYS successful.
I THINK sanding away .005 is one thing, .025 is quite another...sanding machines are a bit much for the average "Little Guy" where you acquire your materials can have a marked affect on the finial product, it's tone AND it's fit and finish.


May 08, 10 | 3:27 pm

Total Topics: 27
Total Posts: 668
Ray, I live in a relatively small town, but still have both a "fine wood" supply house and several cabinet makers who have thickness sanders. They have always been willing to sand my top and back plates to whatever I want them.

Checking the thickness of the spruce top plates from LMII, John Hall (assume it is a Martin plate) and Steve Kovacik (ditto) - they have all been very close to 0.105 - 0.110 as measured with digital calipers. I have always purchased my sides prebent - I figure the supplier will thickness them correctly before bending, and backs have been 0.110 to 0.125 (which I had reduced to 110 at the cabinet shop).

On two of my guitars (the ladder braced 12 and koa tricone) I asked LMI for special thickness - they were right on the money. Btw - I also had a cabinet shop run an ebony fretboard thru their sander and got some chip out.

Oh, last comment, the thickness sander measures in mm - be sure to know what you want in mm or take your calipers with you and measure each pass.

May 10, 10 | 11:29 am

Total Topics: 21
Total Posts: 190
Ahhh, great news Freeman..I had the opportunity to acquire some fine looking stuff..but no way to size it..I'll check it out...thanks.

May 10, 10 | 11:50 am

Total Topics: 18
Total Posts: 165
I haven't used their services yet, but did find a cabinet maker/antique boat restorer in my area who said that they frequently thickness sand stock for hobbyists. So apparently it's a common service they provide.

All it takes is a few phone calls.


May 10, 10 | 12:49 pm

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