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Lets build something that looks like an ES-175

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  • #31
    Great informative thread as usual FK, thanks for sharing
    Music is a moral law. It gives soul to the universe, wings to the mind, flight to the imagination, and charm and gaiety to life and to everything. - Plato

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    • #32
      Thank Ratae and Kwak. I'll return to your comment in a minute.

      While the top is flat I lay out the f-holes



      I was planning to use a follower bit in my little router but didn't have one small enough so I'll just cut them by hand. The little red line is supposed to be a sighting line for the saber saw - doesn't work too well



      Use the template to clean the hole up, I'll finalize it later (still haven't decide to bind the f-holes or not)



      This will do for now

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      • #33
        Man - I would never have been able to make that sabre saw cut. That top would be in 2 pieces again, at least...

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        • #34
          With you there koiwoi. In fact the most adventurous woodworking I ever do involves simple sawing in straight lines; and even then it often ends in tears or hilarity.

          Enjoy watching others with the skills to do it though. Looking forward to seeing how this turns out.
          Last edited by Surrealistic; 08-06-2014, 05:52 AM.
          http://www.surrealisticpenguin.com

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          • #35
            Some threads are just head and shoulders above the rest.

            This is one. Thanks.
            Don't pick a fight with an old man,
            If he is too old to fight, he'll just kill you.


            '' Who, me Officer?''

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            • #36
              Originally posted by kwakatak View Post
              Great lessons, Freeman. It's always a fascinating read to hear one's thinking behind these little structural tricks. I can't wait to see how the decorative stuff comes out later on.
              Might be a good time for some left brained lutherie. Most of this is pretty ordinary - I'm expecting problems with the cutaway and the floating fingerboard is new. But the main thing I've been thinking about lately is how to make the top work. Follow, if you will, my thought process.

              First - what this is NOT. It's not an ES-175, which would have a laminated (yeah, plywood) top pressed into shape under tons of hydraulic pressure. Somewhere on the web there is a video tour of the Gibson plant where they show making this style top. The ES would have large braces in kind of a ladder form to support the pickups. As I have said before, this is not an ES-175

              It is also not an archtop, altho it does take a few things from that type of instrument. A true archtop would have a top carved out of one thick block of spruce - both the outsides and inside is carved kind of like a shallow bowl. No matter how you make them (by hand, with a duplicator or cnc) there is a heck of a lot of hand work which partially explains why real archtops sell in the five figure range. Typically they have a simple X brace or sometimes just two little braces like this mandolin - the feet of the bridge sit over the brace and it helps dissipate the vibrations into the top



              Also, it is not a pinned bridge flat top, altho again, I'll take a few things from that style bracing. Most steel string flattops use the Martin style X (you know I could talk about this stuff for hours but this is an electric forum). The bridge is under rotational forces from the string tension and wants to pull up in the lower bout and be forced down around the sound hole - the X is a very elegant way to counter these forces. Little braces called "tone bars" allow the builder to modify the stiffness of the top which has a dramatic affect on tone.



              What I want to do here is get a bit more dome than a standard flat top. I want to support that with an X that is will help hold the shape as well as fit under the feet of the bridge to transmit vibration. I'm going to put a transverse brace in the upper bout, again to hold the shape but also because cracks can occur from the neck extension. I think I'll put a very small bridge patch in - not sure why, just seems like a good idea.

              If that makes sense, lets build it.
              Last edited by Freeman Keller; 08-06-2014, 07:02 PM.

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              • #37
                First cut some braces. How about 5/16 wide and 3/4 tall - remember that the strength (stiffness) of a beam (brace) is proportional to its width (make it twice as wide its twice as stiff) but proportional to the cube of height (make it twice as tall, it will be 8 times stiffer). Sand them to 15 foot radius (just happens I have that dish and it will make about the same dome as an ES-15





                X marks the spot - glue them to the top against the 15 foot dish



                Add the transverse brace and bridge patch



                And let the glue cure overnight

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                • #38
                  Interesting. I see the similarities with your mandolin build. It kind of reminds me of a hollow body an uncle of mine once had. That was a very light instrument with an almost "nasal" unplugged tone. I wonder: have you ever played such a guitar?

                  I also see that you're using a radius dish. What's the radius? 12'? 16'?
                  Cornelius Clodhopper

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                  • #39
                    Originally posted by kwakatak View Post
                    . . . I also see that you're using a radius dish. What's the radius? 12'? 16'?
                    It's 15':
                    Originally posted by Freeman Keller View Post
                    . . . 15 foot radius . . .
                    Official HCAG “Theory-Challenged Hack”
                    Member of the IBANEZ ACOUSTIC ASSASSINS
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                    Person-2-Person on the Web

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                    • #40
                      I assume he meant 15 inches, not 15 feet. It's a big hunk o' wood if it's really 30 feet across.
                      http://www.surrealisticpenguin.com

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                      • #41
                        Originally posted by Surrealistic View Post
                        I assume he meant 15 inches, not 15 feet. It's a big hunk o' wood if it's really 30 feet across.
                        15 foot radius doesn't mean the top is 30 feet across any more than a 12 inch radius means a fretboard is 24 inches wide.15 foot is the radius of the arch top

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                        • #42
                          Originally posted by Surrealistic View Post
                          I assume he meant 15 inches, not 15 feet. It's a big hunk o' wood if it's really 30 feet across.
                          If you were to hang a pendulum from a tree with a 15 foot long rope and start is swinging it would just graze the contour of the dish. Shades of Edgar Allen Poe....

                          It also means that the center of the lower bout (which is 16 inches across) will be approximately 3/8 inch above the rim - this is very close to what the ES is.



                          Most "flat top" guitars have a slight dome - usually about 25 foot radius and the 15 foot is pretty common for the backs. I'm just making this one 15 on both top and back

                          (I'll add that I'm going to start using a different camera - these pictures are really crappy)
                          Last edited by Freeman Keller; 08-07-2014, 10:39 AM.

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                          • #43
                            Set the top aside and glue the center reinforcing strip to the back. This is simply a piece of Spanish cedar cut with the grain going across the seam



                            And add the braces to the back. Simple standard ladder braces with a 15 foot radius



                            Note, I only have so many go-bars of each length so I put little wooden blocks under them to both distribute the clamping pressure and to adjust the length to whatever I'm trying to clamp. A go-bar deck can apply an amazing amount of clamping pressure.

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                            • #44
                              I like the idea of arching the top more....given that this guitar is going to deal with downward bridge pressure and not the pull of a standard flat top. I see you used a maple bridge plate more in keeping with a flat-top's having to deal with metal ball end pins. I would have probably used spruce instead but no big deal. I would think, though, that bracing should follow an archtop's pattern more than flat-top just based on the task that soundboard is required to do.

                              An archtop guitar is usually braced less than a flattop because it is subject to less stress under load. This is basically because the strings don't anchor into the guitar face and some of the stress is carried by the tailpiece anchored to the box edge. The trap one could easily fall into is bracing this archtop like a flattop because the top isn't carved....when in reality it's functioning more like an archtop.

                              I would brace it a little more than a standard archtop because a truly carved spruce top is a little thicker than plates designed for flattop guitars. But not by much. You're basically bracing so that the top doesn't sink. Bracing at the edge not being that critical because the top is being pushed into the sides...not pulled away. I probably would crave all braces so they are nothing by the time they reach the kerfing. And just brace a tad heavier to compensate for the top plate being thinner than a truly carved archtop.
                              Originally Posted by DToad:

                              Lets face it- today's GOP is all about the richest one percent exploiting the dumbest fifty percent.

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                              • #45
                                Originally posted by gardo View Post
                                15 foot radius doesn't mean the top is 30 feet across any more than a 12 inch radius means a fretboard is 24 inches wide.15 foot is the radius of the arch top
                                Clearly not - but it does mean a 30 foot circle diameter. You have to remember I know nothing of woodworking. I spent a year in woodwork class and failed to produce a single usable item.

                                Please carry on and feel free to ignore me
                                http://www.surrealisticpenguin.com

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