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hi,

my builds always tend to be on the heavy side, i am more than happy with the sound and resonance, but i think my next build should be lighter in weight as a challenge.i went into a shop recently and picked up some mid ranged acoustics and they felt half the weight of mine!!!

there are obvious things that add to the weight on my builds - ebony fretboard and bridge, closed tuners, maybe backstrap laminates?

I'm planning on building a oo size next, maybe all mahogany

do you just go thinner on the the sides back ? anything im missing or doing wrong?

thanks



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1. Eliminate 6 ounces by using open-back tuners with press-in bushings
2. Avoid blended wing and body bridge designs (aka, 'stealth' or bridges without defined wings) - the common Martin 1930's belly bridge design is lighter, and when executed in brazilian rosewood is quite light...figure 1/3 ounce weight savings over ebony
3. Go to thinner sides with better bending support (no two-ply molds - go to three ply or solid); use SuperSoft II to avoid rippling of acacia, mahogany, ash, or maple sides

_________________
For the times they are a changin'

- Bob Dylan

What is your weight?
1974 Martin 000-28, Rosewood, Sitka, closed tuners, ebony FB and Bridge - 4.3 lbs
1933 Gibson L-00, Mahogany, Red Spruce, single action TR, open back tuners, Rosewood FB + Bridge - 3.3 - feels very very light

Are the bushings even necessary? I have not used them except for one out of 8 and after 6 years, the first shows no signs of wear in the hole.

Ed

I just went to Elderly Instruments today. Didn't see any elderly ones? Where do they hide them? I handled about a dozen guitars. All felt heavier than the one I'm building. Some were MUCH heavier because of the electronics. The heaviest thing on mine is the neck. I could probably have made it thinner, but I don't know how thin you can go under the truss rod. So instead I made something like a Clapton v neck. It is still heavy; because I went .93/.98 instead of .85/.93, but the v is flatter, and not as round. That's my story, and I'm sticking with it. I don't know what I'm doing.

Probably the biggest problem with the heavy neck is Birdseye maple laminate with a Padauk middle. Mahogany or Cypress would be a LOT lighter. Even walnut would be lighter. I am going to use open back Grover ukulele tuners. Needs a 7/16" headstock. They weigh 16 grams each. They should work. I think.

I have thin linings, thin sides 1.5 mm (bent them with a violin bending iron by hand, no backings because it doesn't really work with the way the bends go.) and fairly light back and belly, (it's an arch top, so braces aren't there, but all acoustic). It does have two thin redwood tone bars, but they are light. The ribcage surprised me at how heavy it was. I could have used something lighter, like spruce, I think I used poplar.

I have no idea how heavy guitars are supposed to be.

Ahh, some weights while I was going on and on and on.

Violin makers talk about weight all the time. I've never had a weight problem, but some of my violins could be lighter. Violins are so small, fingerboards and tailpieces, and heavier pegs can make a difference. Obviously the weight is all over the place for guitars because there are so many different kinds. Mine weighs a little over 1500 grams (3.3 pounds) without strings, bridge, nut, and tailpiece. A Gretsch with pickups and knobs and stuff felt like it weighed twice that.

Balance will affect the feel too. Mine feels balanced holding it at the base of the neck at the cutout . You can flip it with your wrist.

I don't know anything about guitar acoustics, but is sustain generally helped by a certain amount of weight; or at least weight in the right place? Where would the right place be?

I'm not a guitar builder, so I am shocked, well at least very surprised, at how massively built some guitars seem to be. Does it really HAVE to be that stiff? Especially the sides and rims. I'm thinking that it has to be for sound. A feather light flamenco guitar will NEVER sound like a good steel string, A Gretsch arch top will have a far different sound than mine will have.

What do you think you are missing by having more weight? Response? Projection?

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Why be normal?

The guitar you show us in the photos looks beautiful - so I make the following comments not as criticism, but just commentary where I would see an opportunity to go lighter.
1. Slotted headstock?
2. If you don’t want slotted, you could still thin down the headstock, and do without the backstrap and volute. Your headstock could also be shorter.
3. You could definitely take some thickness out of the wings of the bridge
4. A smaller body size will allow you to get away with thinner back and sides, and soundboard. Try thinning the bridge plate too.
5. Trevor Gore has described a method for making strong light bridges with a wood and CF sandwich.
6. It looks like you have a fairly thick neck profile? A lot of a guitar’s weight is in the neck. Try a couple of Taylor guitars, which have pretty slim profiles, and see if you like it or hate it.
7. Laminated ply tail block can be smaller, lighter and stronger than a solid mahogany block.
8. Do you put side reinforcement struts in? Leave them out, or replace with cloth strips.
9. To get more radical - CF tubes instead of truss rod in the neck. I haven’t tried this myself but It must save a lot of weight to get rid of the metal rod and remove a significant amount of wood for the hollow CF tubes.

What is the weight of that one? 4lbs is pretty typical for steel strings. The lightest I've managed is 2.93lbs (13 3/8" lower bout width, 18 1/2" body length, oak back/sides, 12 fret cherry neck), but I'm an extremist

Try weighing each piece on the next one to see how it all adds up.

More important than total weight is to maintain good balance. If you like the feel of your current guitars, then make sure you remove some weight from the neck end to balance out the smaller and lighter body. Or use a 12 fret neck. With a cutaway and low profile heel, the playable range before you have to take your thumb off the back of the neck is about the same as a 14 fret cutaway with chunky heel. Spanish cedar is a wonderful wood for reducing neck weight.

If you like closed back tuners, I recommend Gotoh 510 minis. 200g stock weight, and 170g if you make wood buttons for them. For comparison Grover sta-tites (open back with metal buttons) are 160g. But open backs with wood or plastic buttons are more like 130g, so that can be worth doing. The lightest of all is Gotoh stealth at something like 80g. They look a bit ugly and delicate, but as long as you don't bash them into anything they work fine.

The whole headblock/heel/hardware business is often pretty massive. It's near the middle so it doesn't affect balance much, but if you want to minimize total weight, this is a prime target. Dovetail is lighter than bolt-on, bolt-on with glued extension is lighter than full bolt-on. Integral neck is the lightest of all, but most people hate them. I use hide glue, easily repaired shellac finish, and no back binding as accommodations for the heel slip reset procedure.

Truss rods are heavy. Single compression rod cuts it in half.

Back and sides can be heavy if using something like cocobolo and leaving it thick. Side mass is generally considered to be good for tone, but if you want mahogany to match the weight of .080" cocobolo sides, you'd have to make them .150" Conversely you could thin cocobolo to .050" and still be a bit heavier than .090" mahogany. And if you use full-width side braces, it will be strong enough too (unless it goes squiggly when bending due to the interlocked grain, and you want to sand it perfectly flat).

IMO a thick rosewood back is a waste of good wood. Better to thin it down so you can hear its contribution to the tone rather than being a dead weight that would work just as well if it were a thick laminate of random wood veneers.

If you really want to save weight on the fingerboard, laminate 1/8" of high density wood onto 1/8" of mahogany or whatever. But fingerboards aren't all that heavy to begin with, so IMO not really worth the trouble just for that. But if you're resawing boards then this is also a good way to get more mileage out of them.

The tail block is also a lump of dead weight. As long as it provides enough glue area to join the sides, some thickness for a strap button or output jack to grip, and doesn't break when dropped on said strap button or output jack, it's good. Cross grain lamination provides much more split resistance than increased width or thickness of a solid block.

Neck material can add quite a lot of weight. Many older guitars (1920's and1930's) used Spanish Cedar or lightweight Honduras Mahogany.

My all mahogany double ought weighs 3 pounds 15 ounces ready to play



I would have to go back and look at my notes but I believe the top was about 0.110, back about the same and sides 0.070. It is bound (but you can't see the binding), ebony f/b and bridge, mahogany neck, slotted head, double acting rod, yadda yadda. What I would call medium scalloping



I made no conscious effort to save weight but it feels light when I pick it up. FWIW, its loud and a pretty good sounding little guitar - you'll enjoy having one in your quiver

How about avoiding a truss-rod entirely and using bar frets? The 1933 OM-18 we just finished refretting is 3 pounds, 7.3 ounces, after adding almost a half ounce of new bar fret wire (the old wire had been raised a time or two and then milled down to just 0.028" height...not that much wire left in the slots).

This week marked my return to the shop after a lengthy break for some family issues, and I ended up completing the OM-18's refret (level, level, level, level some more/crown/polish) to let the boss move onto other work. The neck is amazingly stiff with the bar frets, and to my ears the instrument has a different, crisper tone than the T-fret Martins from the mid-1930's that I have worked on, although that is likely as much scale length, bracing differences, etc., as the fretwork.

I finished the fretwork Friday in the early afternoon, then strung up with lights...initially, I saw just 0.002" relief, but that stabilized at 0.004" by early Saturday AM when I arrived, and allowed final setup on the nut and saddle. As Mr. Morelli often opines, no good deed goes unpunished, which was the case here with the customer changing his mind on strings at the last minute. Restringing with a set of EJ-19 med/light split gauged bluegrass strings gave us 0.005" relief - still acceptable. With an average fret height of 0.050", the instrument prefers a light left hand.

I'm thinking of adding a reproduction OM (with early 1930's bar frets and ebony reinforcement) to the list of things to build...wonderful instrument, despite the truly amazing amount of time spent leveling what was much harder wire than we pulled out of the instrument...this old wire was likely from a mid-1970's refret, and softer, lower nickel content material versus Mr. Thompson's harder 30% nickel reproduction wire.

_________________
For the times they are a changin'

- Bob Dylan

We use 12mm (0.44 in) Baltic birch for most of our tail blocks, although primarily for split resistance versus weight savings, considering how many guitars see pickup installations. Baltic birch ply runs about 38 lbs/cubic foot, versus about 30 lbs/cubic foot for solid mahogany, but at 58% the thickness of a solid block, the ply tail block ends up close to an ounce lighter in total weight versus solid wood. ApplePly or some of the 'lite ply' alternatives are about 75% the density of Baltic birch ply, so would save some additional weight at the cost of some potential changes in workability.

_________________
For the times they are a changin'

- Bob Dylan

Ruby 50 wrote:
"Are the bushings even necessary? I have not used them except for one out of 8 and after 6 years, the first shows no signs of wear in the hole."

You can use shelf pin sleeves instead of bushings for weight savings and that old time "vibe". I'm pretty sure that is what the old Gibson's have:
https://www.widgetco.com/shelf-pins-1-4 ... fcQAvD_BwE"

If you want to build a lightweight guitar use Formica for the back and sides and WRC for the top. Skip the bindings so you only need a thin strip of wood for the linings. Formica would allow you to use a single long strip for the sides, reducing or eliminating the need for a tail block. A one piece formica back would only need a couple of light braces and no back graft. A single action rod in a cedar neck with a set of cheap Chinese tuners (slightly thinner metal) or friction pegs might keep the neck weight down.
Am I being facetious? - Yes, somewhat. You said you liked the sound you are getting with your guitars. How did the sound of the "mid range acoustics" compare? I like to use African blackwood for bridges, which some people think is too heavy. I like the sound I get with it, so I don't worry about the weight. As long as a guitar balances well I don't worry about the weight.
Perhaps there should be a challenge to build a one pound guitar (with standard tuning - no guitaleles allowed!) A gossamer guitar, like the gossamer albatross, totally impractical, but a thought experiment brought to life.

I will add my 2 cents here
On using bar frets and do truss rod , Not on a steel string you need something in there. Martin used Ebony , Tee bars and square tubes. Also the aluminium 1 way rod.
Carbon fiber and bar frets would be lighter and more stable.

One other thing is this. Be aware that light is ok as long as the stability is not compromised. CF Martin has a series out the called the CEO and is very light and I see way too many in the shop for top belly and other issues so there is a point that you can make it too light and create more issues. Lighter is not always better.

So what thickness is your top?
What braces and are they scallopped
What bridge plate?
How thick are the side and back.
What size bracing on the back? width and height
did you radius the top braces?
what size neck block? In 39 martin changed the neck block thickness and as a result tops imploded and the Popsicle brace was used . They were always in the 12 fretters.
how thick is the fret board?
The head stock can be 5/8
what finish and how thick?
Side supports?

so there are areas you can cut weight and some areas you shouldn't. I know some will disagree with me but having been in this business for over 20 years I have seen too many "light guitars" implode.

I have seen 1/4 in scallop top brace guitar ( Martin HD35 ) and these things will belly like crazy do understand the variable and then the best advice is to make an experiment to see what will work best for your design. Things like

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Cablepuller - what's he weight of the instrument i questions? If you don;t have a scale, the PO, UPS, the grocery store, etc, can weigh it for you.

Ed

This is kind of interesting - I just weighed my 1974 D-18, its from the "over built" era, however the bridge plate and tuners have been replaced. It weights 3 pounds 14.5 oz, actually lighter than the smaller 00. Must be the light gauge strings

Cable, your build in the photos looks really nice...



This one will be lighter no matter what else you do.

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

Where the weight is is more important than what it is, in many respects. Some people like to make the rim heavy (Trevor Gore bolts on weights!) to help 'keep the sound in the top'. Others make the back heavy and/or stiff so that it will be 'reflective' rather than 'active'. Each choice gives a different sound. There's no
'right' or 'wrong' weight in any absolute sense; it all depends on the sound you're shooting for.