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I've set a goal for myself to build a guitar (at some point) that is below the 3lb thresh hold. For no reason other than to do it and see what it sounds like. I had a Kel Kroydon pass through my repair shop recently and it barely passed the 2lb mark. I don't want to get that crazy but I thought it would be a good exercise for myself and hopefully I can learn something from it.

That being said, your average 2 way truss rod adds a decent bit of weight to a neck, is there a version besides a compression rod that is significantly lighter than the norm?

Dan,
You must of missed Stuarts discussion on truss rods.
here's a link.
viewtopic.php?f=10101&t=54362&p=714033&hilit=truss+rod#p713245

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Jim Watts
http://jameswattsguitars.com

Apparently the original didn't have a truss rod.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

What's wrong with a gibson style compression rod? I use them in my guitars. You can't get much lighter.

I don't mean to side track the discussion on light weight truss rods, I don't have any input on that, but I wanted to ask what the normal weight range is for an acoustic.

I ask because I was surprised by the 3 pound goal. I never really weighed a guitar before but that sounded like pretty attainable without drastic measures. So I grabbed the two guitars I have next to me and put them on the bathroom scale that is right here. I fully understand that this is not a reliable way to weigh a guitar but I wanted a very rough ballpark estimate. Both were under 3 pounds with my suspect measuring set up. To be fair, they are both small 12 fret guitars. The walnut, cedar O with mahogany neck is noticeably lighter than the even smaller parlor with Katalox back and sides and a hard maple neck. The walnut guitar was about 1.5 pounds and the heavier katalox guitar was just a smidge over 2 pounds.

I never really gave much though to over all weight. I think about the weight of the top and bracing, the weight of the bridge and the weight of the neck (but only in the context of if it will cause a balance issue). Is total weight something I have been neglecting?

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Man, you're building feathers.

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Hutch

Get the heck off the couch and go build a guitar!!!!

- 1.5 pounds!!
That's less than 770 grams, methinks your scales and or method is a bit suspect.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Bathroom scales are very inaccurate in the single digit range.

Darnit, see I didn't want to derail the thread. Yes, I felt like I acknowledged that my measurements were not up to snuff, at least I intended to. My question was more about 1) what is a normal range trying to glean both average weight and how much of a variance people are seeing in that range and 2) is this something I should be worrying about. If total weight isn't really a telling metric then I don't need to worry about finding a way to measure it accurately. . .

Edit to add:

Yes, I don't think that my guitar is 1.5 pounds. I probably should have left my numbers out all together. For me the measurements were not about accuracy but I assumed some small degree of precision between them. I was trying to point out that my smaller guitar was more than 1/3 heavier and I never bothered to worry about that. I expected it to be heavier since it was made from denser materials, but. . . was I making a mistake in ignoring that as a consideration when I made them?

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

This is what I was going to suggest too and you can make your own easy enough. Dave and I have fancied a line of guitars from time to time and we both thought that a compression rod would be what we would do too.

Stuart's rods will be the best if he decides to make multiple lengths and sell them. The only thing lighter is a titanium or aluminum compression rod. Aluminum would need to be at least 1/4" diameter to compensate for the lower strength, but would still be 3/5ths the weight of a 3/16" steel rod.

Allied Lutherie has an ultralight truss rod design which I think uses 1/4" aluminum plus a C channel as the compression member. It's still a one-way rod, but apparently possible to install it such that you can take the neck off and slide it out and flip it upside down if you ever need to induce forward bow.

The only real danger with compression rods is leaving them tensioned while the strings are off for a prolonged period, which can cause permanent backbow in the wood (it's basically a big fat string that counterbalances the other 6 ). That, and if you use the Gibson style, the large cavity for the adjustment nut makes the headstock break off more easily if dropped.

Gotoh Stealth tuners are another boon for ultralight guitar building. Expensive, ugly, and delicate, but only 13 grams each (78 grams for the set). The next lightest I know of are StewMac's economy open gear tuners, which are 120g. Again delicate and not great looking, but they work fine, and the whole set is cheaper than one Stealth Gotoh 510 minis are 200g stock, but you can replace the buttons with wood to get them down to 150g.

If you're going to use a bolt-on neck, aluminum or titanium hardware will save you a bit of weight. But you'll probably at least need dovetail to break the 3 pound barrier on a steel string. I've only managed it with an integral neck and Stealth tuners.

Normal weight for steel strings seems to be around 4 pounds in my relatively limited experience. But varies with size, obviously. Use a small kitchen scale of the type used for weighing food. The tiny ones with 0.1g resolution and 2kg max are also good.

I understand why a builder might want to make certain components (bracing, bridge) ultra light in order to make an acoustic instrument more efficient, but why the neck? I’m presuming ergonomics?

There’s some parts of a guitar where making them as light as possible would negatively impact the sound of the instrument… at least In my mental model of how guitars work …

To me a lot of guitars are neck-heavy. I don't like that feel, because the LH has to hold the guitar up,
as well as fret the strings. I've thought that balance point- measured with the guitar placed upside down
on the fingerboard, naming the fret where it balances- could be useful as an objective
measurement for players. One POV.

I just weighed one of my lightest. It’s a walnut back, sides, and neck, OO-sized. It came in at 3 pounds 13.5 ounces. Most of mine (usually larger) seem to come in in the 4 to 4.5 pound range. I do everything I can within reason to keep my builds light. I use spruce tailblocks and Gotoh tuners with wooden or plastic buttons. If I could remove more weight without compromising function, I would. I always make the neck block out of the same wood as the neck, so going to spruce there won’t work for me. I use the StewMac double action rods. The one I just checked weighs 4.6 ounces. Eliminating that still wouldn’t get me below 3 pounds. Beating 3 pounds is an interesting quest. That’s going to trouble me until I can figure out how or until I decide it can’t be done by me.

I'd like to get some specs on Gotoh classical tuners with (apparently) CF mounting plates, but haven't
been able to find any info on them other than a photo. A heavy bottom block can help with the neck balance issue, too (I've used Jatoba, so far).

Somehow I did miss that. Thanks Jim! I'll read through that thread too.

To me I think i just enjoy a little quest every now and then. The Kroydon I had in weighed at 2.2lbs which is feather light. It sounded incredible with just a cavernous woody sound. I think i would enjoy just trying to replicate that for the sake of knowledge and it would just be plain fun and challenging. 3lbs i just felt was a decent goal which as proven by some already made guitars is completely attainable.

As a side note. The way the Kroydon was able be below 3lbs was that pretry much every part of it was extremely thin. The fingerboard was ludicrously thin at barely over 1/8 thick. The top was paper thin as was the back and sides
No truss rod at all. The frets were crazy small and crazy short. The bridge was very thin a d very small. The braces were barely 3/16 thick and the back braces were tapered to a ridiculous sharp edge which lightened them further. The blocks were I think poplar? But again thin and light. The bridge plate was stupid thin too and looked like paper.

I was kind of shocked that it had even survived this long. It's a wonder it hadn't collapsed in on itself over time. But it did sound really good.

Wow. And regular light steel strings on it? Or something lower tension? What kind of tuners?

It's pretty easy to get below 2lbs with nylon strings if you use wood friction peg tuners, but I wouldn't have thought you could get close to that with steels and survive for long.

I have considered using 1/8" fingerboard wood laminated with something lighter and then covering the edges with binding. If I had room for a bandsaw to process wood myself rather than buying standard thickness fingerboard blanks, I would have done it that way from the start just to conserve rare woods.

Personally I wouldn't scrimp on soundboard brace wood. It's such a small portion of the overall weight, and such a large contributor to the longevity. Certainly you can use tall narrow type back bracing rather than the Martin style fat ones, but I'd stick with at least 1/4" width for better high humidity tolerance. One style I've used is to start with fat braces, but carve them with a gouge to a sort of eiffel tower profile. More glue area, but not a lot more weight.

I recently finished a Mahogany L00 that weighed in at just under 3 1/2 lbs.
The lightest I have seen is the D'Angelico style rod, or some version of that in a dual action truss rod. The ones that I made were of Stainless Steel 304L.
This style rod is used by many of the local builders and at least one went to, and may still use Titanium to shed even more weight. I consider Mark Blanchards truss rods to be a variation of these rods.
I would not use Aluminum for a rod for several reasons, mainly based around the integrity of the threads, torsional strength and dimensional changes based on temperature.
Not really familiar with Stuarts' rods but if I remember correctly in one of his postings they were fairly expensive to make.

IMHO if a guitar is made too lightly the sound can lose some of its' complexity. The only guitar that I have that has come in under 3lbs is a 1921 Martin 0-18, a lot of different reasons for why.

> IMHO if a guitar is made too lightly the sound can lose some of its' complexity. <

I think I hear that, too. Generally a quicker but simpler, more unified response.

Quicker attack but also quicker decay.
I also have a kept the 000 12fret I made with Panama Rosewood out of Panama Rosewood, slot head, that weighs in at just over 3.5lbs.
also had a '33 Martin OM that weighed real close to 3lbs. That one pushed the limit a bit as far as plate thickness.
Good place to reduce weight is in the neck and head IMHO, as long as the guitar stays balanced weight wise.

Tuners were the pre-war old 3 on a plate style with plastic buttons. I think the thing that really affected the weight more than we think is the fingerboard thickness. A 1/4 slab of ebony/rosewood is going to weigh alot more than something that's 1/8 of the same species even.

For my own builds I won't go that crazy thin with things overall. But I think with thinner back/sides it'll really make a difference. One thing I'm trying with my current build is the G-bson style tapered headstock to reduce the "neck heavy" thing as mentioned before. I might try a guitar with 3/16" wide bracing but leave it tall?

Since the sound was mentioned, the Kroydon has a crazy fast attack, almost too fast for some folks. And it was strung with 11-52 regular steel strings. A light fingerstyle approach sounded awesome on it but anything with a pick was a little too much and the top would get a weird compression sound to it.