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So here is the second attempt at bracing this top - I trotted out the first attempt at our Tampa Bay get together last weekend and after the laughter subsided, took off the braces and re-braced it. This is a Sitka top that is going on a Cherry OM. The top has a good ring to it, more so further down in the lower bout than around the bridge plate, but with no real baseline for me to compare to, I dunno what I dunno...

Anyway, take a look and tell me what you think...

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Mitch

It is hard to tell because in the photo it is hard to truly judge scale. To me almost every brace seems to have too much mass left on it. It is as if you left the braces rectangular and just rounded over their tops. I think the tone bars are far to close to each other at the intersection with the X brace. It is hard to tell for sure but the UT brace appears to flat toped and a bit thin. Especially if you do not intend to have a UT graft.

The work does look good and neat

Well guys....I saw Mitch's first brace work. I think Mitch knew it needed work and that's why he brought it out. This look 100 times better.

With the preamble that I have only done one guitar.......I think you could stand to take more off. It took me 3 whole days to carve and tap and carve and tap and carve and tap. Mostly because I was scared to death I would take too much off. If I had it to do all over again....I wouldn't be scared to take too much off. It is likely you will overbuild this guitar because of your furniture background. We furniture makers tend to do that.

Look at it this way. Let's say you DO take too much off - you get to build another one.

Michael P is right you will need to put something above that UTB in the upper bout. I did EXACTLY the same thing as you when I did my top. When I attached the neck to the body I became suddenly concerned about the force that fingerboard extension will exert on the top in that area. I went in AFTER the build and added a brace. What a pain in the butt that was.

Your tap tone near the edges will be louder than near the bridge plate no matter how you brace it. However, since the vibration that makes sound is going to emanate from the area of the bridge plate...I did my tapping and judging from there. That's my thought on it anyway....certainly not science.

Get your finger plane or chisel out and go to work. Make it better. Take your time. Less is more. I added a pic of my top. It's scalloped so don't think I am suggesting you do it that way. Maybe it will give you some perspective on height...how much to take off etc.


Chris

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There is no difference between the man that thinks he can....and the man that thinks he cannot.

Mitch my friend let me first say that the work does look very clean!

I agree with Dale.... on all of his points and will add a few too:

1) It's hard for me to see from the picture too, it's fuzzy and not a large picture so some of my comments may be because I am not seeing things correctly here.

2) How wide are the braces. You can go, IMHO, 1/4" wide on the X and other braces except the UTB on an OM.

3) The UTB looks like the ends are feathered away to nothing leaving nothing to inlet into the kerfed linings. I like to see about .010 left to inlet into the kerfed linings. Inletting the UTB is critical IMHO.

4) If you use finger planes and plane the sides of all of the braces, except the UTB, into more of a triangular profile you will lose lots of the extra mass that Dale mentioned.

5) It looks like you intend to inlet the ends of the lower X legs - is this correct? If so this is fine, some inlet these some do not - I don't and feather them away to nothing at the kerfed linings.

6) I agree that the tone bars are pretty close together and could be more distant.

7) I make my X intersection on OMs 1/2" high uncapped and then add a 1/32 - 1/16" cap. A little higher than 1/2" uncapped is fine but I would not go above 9/16"

8) Are the tone bars and finger braces butted or inlet into the X legs? I butt and pare away the ends pretty low until I can hold the top up right in front of me with my thumbs on the intersection of a brace and the X legs and feel a slight amount of flex.

You are very close but would benefit from removing some more mass and repositioning the tone bars.

Nice work!

Thanks for all the input guys!

The X-Braces are 5/16" and the rest 1/4" - I'm about 9/16" at the X intersection, and the tonebars and finger braces do butt up to the X brace...

Snig, you hit the nail on the head - afraid to over-shave and leave a top that falls in on itself...I can definitely remove more of the mass on the braces, and add a popsicle brace above the UT...

Its interesting, as some of the input i have gotten from other builders I highly respect go 180 degrees in the other direction from some of Hesh's suggestions...I guess that is the beauty of finding out what works for "your style of building".

Again, Snig hit it correctly - I'll have more chances to build and compare, refine, and build and compare, but this being my first scratch build, I don't have a "baseline" yet for comparison, so this will be it...

Thanks again guys!

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Mitch

All good suggestions.

OTOH...to install or not install the popsicle brace issue can sometimes be controversial. If you frequent the UMGF (Unofficial Martin Guitar Forum) there are literally hundreds of players who remove their popsicle braces and swear by the improved results. Bryan Kimsey, a well-known repair person and luthier has started a cottage industry in removing these! As far as support, I have made 9 guitars without this brace and 3 have so far survived 5 years with no sign of instability. Consider an A-Bracing scheme in the area as a compromise.

Mainly...get out your finger plane and remove the mass by 30% to 50% and show us what it looks like. Nice work so far!

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JJ
Napa, CA
http://www.DonohueGuitars.com

Referring to what JJ just mentioned regarding the A brace above the UTB instead of a popsicle.......I was actually thinking about doing that very thing on this build.

Haven't decided though.....paralysis thru analysis.....

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There is no difference between the man that thinks he can....and the man that thinks he cannot.

Here is a short story about a kid I know that recently built an OM. He read on a forum (not this one) that you should have popsicle brace behind the UTB and that is just what he did he went out and bought poplar popsicle sticks and added one each side of the FBE. Of course this did not help much but likely did not hurt much either. But we must remember many newbie lurkers here don’t always chime in and we run the risk of misleading them when we use popsicle stick brace to describe the Upper Transverse Graft. This is particularly true if someone building from and older Martin kit as they use to send out real popsicle sticks to use as side and sound hole bracing and one could inadvertently make the obvious mistake.

Besides that an upper transverse graft does not eve look like a popsicle stick in the first place.

Mitch this is a 200% improvement over the first attempt! Well done.

It looks like you now have a pretty tight x-brace joint and I like the looks of what you have except for maybe removing the lower tone bar and moving it down a half inch or so. It is hard to tell how much mass is on the braces, but in general for an OM size guitar I would go for about 1/2" at the intersection of the x and then all of the other braces about 1/4" tall to 3/8" tall at their highest point. I would also leave enough "meat" on the upper legs of the x-brace to retain the rigidity for strength.

I no longer use the Popsicle brace, but instead I have an apron on my heel block that extends almost all the way to the upper transverse brace so that the fingerboard is supported firmly. If it were mine, I would round over the top of the upper transverse brace also.

Well done! Even if you left the tone bars where they are and just remove some of the mass I think you would be happy with the way this one sounded.

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Reguards,

Ken H

Thanks Ken - I'm doing the same thing with an apron on the heel block that I can bolt the fingerboard extension with...

I"ll be working on this later on and post some new pics with all the suggestions...

Thanks again!

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Mitch

Good point Michael - maybe in an effort to keep folks out of the emergency room we should avoid discussing butt wedges....... While we are at it we had better ban photos of how one flosses their cheeks.....

Mitch what kind of things have you been advised to do that are 180 degrees from my recommendations - I am just curious and I understand in advance about different strokes for different folks.

Looks beefy to me Mitch but I'm no expert either. I took a mirror and and looked in side some of my guitars to get an idea of what the Gibson and Martin bracing looked like for some ideas too. Check the stiffness cross grain as you go too. I re did my X braces and Tone bars too. Trianglulate(sp?) the braces from the bottom to the top I would say.

Hi Hesh my friend!

Mostly just the inletting of the X braces - as you said, some do it and some don't - I will do it on this guitar and see how that works out for me.

It appears that pretty much everyone is in agreement that my braces need to go on a diet

I'll also move that lower tone bar down a bit as some have suggested here.

Thanks for all the help, this will make my baseline a heck of a lot better!

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Mitch

I know what someone that mentions the popsicle brace is referring to and a butt graft or butt wedge . However I never understood the term “popsicle brace” for the UTG. Yea it is short and wide but 4 or 5 times wider and 2 to3 times thicker than a popsicle stick, so I never saw the resemblance to a popsicle stick. But it is not a big deal I just thought it might help to save someone some confusion.

Here's another thing you could do, Mitch. When tapping, try to find a place to hold the top—pinching it lightly between your fingers—where it gives you a bonnnnggg sort of tone. I usually find it on my tops just below the upper transverse brace close to the sound hole. When you find it, you'll know by the sound. This spot is one of many all over the top, where top doesn't move as much while it's vibrating, much like the trough between ocean waves. Holding the top at this point of lesser vibration will have much less damping on the top as you tap, compared to holding it in a place where it wants vibrate a lot. The spot will be along a line of other similar points; together they're called an anti-node. If you use this spot repeatedly (you'll probably have to search for it a bit every time) while shaving and tapping, you'll get a better idea of the results.

Pat

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formerly known around here as burbank
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http://www.patfosterguitars.com

Mitch you have the Mayes Voicing tapes don't you? He explains that. Watch those Somogyi videos too.

Somogyi Videos?

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Mitch

I certainly don't mean to hijack this thread, but along Michael's lines of clarity for newbies, I get confused every time I hear about the A-brace instead of a popsicle brace. I find it mentioned many times, but I've never seen it pictured or described on this forum (not to say it hasn't been, sometime, somewhere; I just can't find it)

Could someone please give a brief description of this for me? Thanks.

-Clint

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-Clint Beacock

Michael...Popsicles were a lot bigger back in the Pre-war Golden Age of Martin guitars! <BG>

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JJ
Napa, CA
http://www.DonohueGuitars.com

Here's one I did recently. It is believed to provide more strength in the upper bout area to support the fretboard extension, as an alternative to the flat upper transverse graft (popsicle brace, if you will). It is believed to help spread the shear and downward forces from the neckblock and fretboard extension over a larger area.



Pat

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formerly known around here as burbank
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http://www.patfosterguitars.com

Yeah.

I believe Frank Ford said once that he just loves it when people remove those "popsicle" braces from their guitars.
BTW, I sometimes build with them and sometimes without them. I think the improvement is probably psychological,IMO.

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Jim Watts
http://jameswattsguitars.com

Very nice Pat but your bridge plate looks crooked - higher on the left side.......

Mitch bro I wanted to give you some food for thought and this will also possibly help Rob Lak with his recent questions. BTW I am on the fence about inletting the lower X legs and I can see the benefits of doing so so by all means inlet if you wish. Colin inlets and Colin is the real deal and a guy who I have the utmost respect for.

With the top upright in front of you, braces away from you, visualize the exact half way up point of the top and note the position. You can measure it too to be sure. Now working with just the upper half of the top measure or visualize the 50% up point again and mark it. Another way to say this is you are looking to find a point along the edge of the top that is 25% of the way down from the top of the top. Also go get a board, even a 2 X 4 only shorter.... and find the 1/4 down point - this is what you are looking for and where you hold the top - for now......

This is the point that Pat wants you to hold onto with two fingers close to the edge. Now with your ear close to the top and the top held as described above start tapping with your other hand and one finger. Be sure no one is home or they may want to have you committed.

You will hear places where the top rings better than other places and/or has better sustain and rings longer. You are not looking for a specific note - just a ringing and some sustain. And again always hold the top in the same spot - for now.

You will also hear places where the top is dead and goes "thud." For example the X intersection is notorious for being dead sounding.

So when you hear a ringing turn the top around and note where it rings and conversely when you hear a thud also turn the top around and note where it thuds.

Over braced guitars will thud sure as shooting where ever the braces are glued on and where braces intersect other braces are problematic areas too.

When a top thuds in the X brace's path I remove all the mass that I can from the sides of the brace making a sharp triangular profile to the brace. Then I tap it again and it will start to sound more open and perhaps have some ring to it. If after removing all the mass that you can and if it still thuds, which it may not, then I go after the height of the brace removing some height, reprofiling the triangular profile again and then tapping and listening once more.

You will hear the top open up right before your eyes and this will be your ah ha moment. Seriously.

I start with the X and only the X glued onto the top. I profile it and tap away until I can get the top to ring in all locations where the X is glued on. Again the X is the only brace on the top at this time. Once the X is ringing well all over then I add the tone bars and repeat the procedure concentrating on the tone bars. Next is the finger braces - same deal.

Once all of these braces are on I tap at the intersections of the tone bars and finger braces and the X and I pare away with a chisel at where they butt together until these intersections ring too.

All of the above can be done with all of the braces on as well - I just like to make it an additive process because it is easier for me to wrap my head around it.

By the time you glue on or get to the UTB after doing the above you will know what to do. I also find that gluing on the bridge plate last and shaping it to be where it needs to be but not where it does not need to be that once the bridge plate is added the entire top rings even more resoundingly and longer.

I was hesitant to contribute my thoughts to Rob's thread because every one does this differently and there are many ways to nuke that poor cat - sorry Don my friend.

My goal is to have as resonant and responsive top as possible but still be strong enough to withstand the forces that act on a guitar top.

Once you get the hang of the above you can go for specific notes, apply this to the back and back braces too and also tune the back as well.

Anyway I believe that once you start trying this, profile to a triangular profile first, tap and listen, if not ringing reduce height and reprofile and listen again - you will understand what to do AND you will be tap tuning your guitars.

Good luck.

Yup. The lower spreader is crooked too, so it looks even worse. I've since replaced the BP.

Pat

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formerly known around here as burbank
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http://www.patfosterguitars.com

Hesh, where were you when I posting on bracing and voicing a month ago? Let me get this right buddy. You voice the UTB this way too and the upper X ?