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...on the bridge patch.
Made one of those acoustical p===llel plates (Brentrup LBP...lightweight bridge patch ). Came out 5 grams lighter than a solid patch (same size).
Worth it for 25 vs 30 grams?

Haans: That seems like quite a bit of weight for a bridge patch.If I recall correctly my patches are generally about half that weight. I generally use maple. Wonder what others have noticed for weight.
Tom

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A person who has never made a mistake has never made anything!!!

Haans, it's worth using it just so you can say "This guitar has a "Brentrup LBP".

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I didn't mean to say it, but I meant what I said.
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Tom, It's quite a bit larger than your regular patch...I't (supposedly) supposed to not only be a bridge patch, but replace the tone bars too. My regular patches are around 9 grams (spruce and ebony ball end plate)
Woody, Not so sure I want to waste a top to try it, but was more interested if 5 grams was that big of a deal, especially since I use laminated braces anyway.
I was just sportin' with ya about the name, I wouldn't be so presumptuous as to start naming bridge patches!

I know, but I loved the name.

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

Better inlay a mirror in the back of the guitar to display it's magnificence.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

Haans,
I had the opportunity to check out one of Kevin's guitars built with the bridge patch, it sounded great. There's more to it than losing 5 grams.

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Jim Watts
http://jameswattsguitars.com

Thanks for the input Jim. I suspect a lot of the difference is loosing the tone bars, but I'm just musing about a solid spruce patch the same size. Is 5 grams worth it?

Yea, Filippo, you are right.
I think that although I had some spruce lasered to make the honeycomb, I will just use a solid patch and maybe drill some holes in appropriate places. Patch could also be made thinner the closer it gets to the tailblock too. Think I'll try that and see how the top rings. I can always pry it off again put in a regular size patch and add the tone bars.
Terry, think I'll take a photo instead...

You can loose almost 3 grams going pinless.

3 grams here, 5 grams there...

I think that a 5 gram reduction is insignificant when considered alone. However, if one is going to get that concerned about the reduction of mass one has to be concerned about it everywhere. Mass is accumulated in the system. Just like with our bodies some mass is bone and muscle and some is just fat. The trick on a guitar is to tell which is which.

And Haans... what? No pictures? What kind of bridge plate are you talking about? I claim ignorance.

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Expectation is the source of all misery; comparison the thief of joy.
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Ask and ye shall receive...seek and ye shall find...



Didn't think I needed all the frooferall at the back like the Acoustical parallel dingy...also filled in the holes where the bridge pins go.

OK, here's the patch I'm going with. This one is .095", solid (except for the fru-fru holes). The 30 gram rendition was .105", this one is 20 grams. Lighter than the honeycomb which was .105". Go figure...





Has a nice woody tap to it, but should crisp up with the laminated bracing.

Fascinating! But I'm still trying to figure out what is supposed to do and how?

I understand the lightening holes, but I can't see why it needs to be so big?

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Expectation is the source of all misery; comparison the thief of joy.
http://redrivercanoe.ca/

Haans, I have one of these in progress also, It's a ways off from being finished though as I'm building with my daughter.
Please report back on the results you achive if you wouldn't mind.

Doug, it's a combination bridge patch & brace, replacing the tone bars. Check out Kevin Ryan's site for more information about it.

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Jim Watts
http://jameswattsguitars.com

That's about it Doug, get rid of the "tone bars", although it's beyond me why they call them that. Every other stick of wood on the top is a brace.
Jim, it's kinda spooky not having the braces there, and the problem is getting the patch the right size, but we'll see. I just hope I don't loose that "bluesy sound" for some etherial "plinky" tone. I'm always looking for that FAT, solid tone...
Mine's a long way off too, and it's not like I needed another guitar to build. However, I do have a braced coco back and bent sides. I am tempted to go with white oak though. I have a braced oak back that I could change the center stripe on. Guess a lot depends on how I think the fully braced top taps out.

Here's the braced top ready to final tune. Took a little more off the plate (the Dremel Multi-Max with the triangular sanding attachment works wonders in situations like this) and tapered it. Seems more sensitive than regular tone bar bracing. Scratching the top is really lively.

Haans,

Any update on this one ?

I find it very interesting because while the plate outline looks similar to what Kevin Ryan is doing, The overall bracing strategy looks completely different.

Are the rest of the braces laminated with Carbon or hardwood ?

-jd

JD, I got a lot of flack from someone on another board about it until Kevin stepped in, made some comments and several others pointed out the differences in our ideas. I had all but scrapped the idea and started to remove the plate when the pallet knife took a wrong turn and pushed through the top. Sad to say the whole top is waste. I was quite soured on the whole idea, but proceeded to join a new top, make the rosette and put in the X brace and fingers while thinking the whole situation over. Late yesterday I decided to proceed with the idea, and made a new plate for the top.
I'm actually glad I went this route because in the end, my idea ended up a little more refined and the X braces were made thinner, and I lost 30 grams on the top so far. I will probably lose another 7-10 grams from final tuning and sanding.
My idea (after making a test honeycomb plate and discarding that idea) was to use a solid spruce patch and set the grain at 45 rather than 90 to the top. It is quite different than Kevin's plate. Apparently, he says the idea of the honeycomb plate is to make the area very stiff and light, while my idea is to make the area more flexible than stiff. He says that there is no belly in his tops and I prefer just a bit of belly. I can't say for sure, but my plate looks quite a bit larger than his and has much more recurve.
So far, after drying overnite, the sound of the top is more lively than the other and I haven't even started to work it yet. I have regained some of the excitement that I had lost in the last couple of days. My only regret so far is that I destroyed a beautifully grained red spruce top. I'll get a photo up later.
The braces are rosewood/red spruce ala Larson Bros. The UTB is maple.

JD, I got a lot of flack from someone on another board about it until Kevin stepped in, made some comments and several others pointed out the differences in our ideas. I had all but scrapped the idea and started to remove the plate when the pallet knife took a wrong turn and pushed through the top. Sad to say the whole top is waste. I was quite soured on the whole idea, but proceeded to join a new top, make the rosette and put in the X brace and fingers while thinking the whole situation over. Late yesterday I decided to proceed with the idea, and made a new plate for the top.
I'm actually glad I went this route because in the end, my idea ended up a little more refined and the X braces were made thinner, and I lost 30 grams on the top so far. I will probably lose another 7-10 grams from final tuning and sanding.
My idea (after making a test honeycomb plate and discarding that idea) was to use a solid spruce patch and set the grain at 45 rather than 90 to the top. It is quite different than Kevin's plate. Apparently, he says the idea of the honeycomb plate is to make the area very stiff and light, while my idea is to make the area more flexible than stiff. He says that there is no belly in his tops and I prefer just a bit of belly. I can't say for sure, but my plate looks quite a bit larger than his and has much more recurve.
So far, after drying overnite, the sound of the top is more lively than the other and I haven't even started to work it yet. I have regained some of the excitement that I had lost in the last couple of days. My only regret so far is that I destroyed a beautifully grained red spruce top. I'll get a photo up later.

Looking forward to the results!

_________________
Expectation is the source of all misery; comparison the thief of joy.
http://redrivercanoe.ca/

If I may throw in my opinion, it looks slightly unbalanced in terms of how the bracing covers the top. I'd still add one small tonebar close to the bottom if I was trying this.

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Build log

Haans,

I do think you are on to something with this. I too have been trying to figure out how to eliminate the tone bars. My approach was using carbon to get a very light plate, but always have problems at the edge. If i extend the carbon to the lining the top is too stiff, but if I stop the carbon before the lining strange stuff happens and the boundry between the stiff plate the the much lower modulus spruce top. I also tried a zig-zag edge since I really couldn't thin the carbon effectively to ease the transition.

By using a spruce plate at a bias to the top you eliminate the abrupt transition in stiffness at the edge of the plate.

-jd

OK, here's a photo of the completed, ready to glue on top, but not fully worked yet. Plate is a bit larger and there is more recurve at the rear. Here is the a recent GC with Larson X bracing, the "dead" top and the new top.







Alexandru, the plate worries me too, which is why I made it larger. I will see what it works out to as far as deflection when It's glued on to the ribs, and make a decision at that point as to whether to add anything else as far as bracing (wouldn't be my first choice).
JD, just as Kevin was put off by non-organic honeycoymb, so am I, so I figured that a plate of spruce might be just the ticket. It has a very lively tap.
My only problem now is deciding on the B & S material. I'm inclined to go with my favorite, white oak, but my wife says I should go with something more mainstream like IRW.

Ohh, who listens to their wife anyway...and stays married?!


...I do. She's a smart cookie.


But sometimes you just know in your gut what you gotta do regardless of the opinions of those around.

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Expectation is the source of all misery; comparison the thief of joy.
http://redrivercanoe.ca/