Ok, so now I'm looking at my broken cheap acoustic. I pulled the piezo rod and bridge, very cheap bridge, just drilled thru holes for the strings, etc.
For 6 bucks I got a tune o matic type wooden (ebony) bridge for an archtop, so the base and saddle are both curved slightly. For the base, since contact with my flat top would be on the ends. Should I leave it arched, or sand it flat for 100% contact? I am going to replace the saddle with a piece of aluminum angle.
I forgot to mention, this is a conversion to steel.
Better contact the better the sound.
thx. I wasn't sure, seeing arched bridges and such...
The arch in the base of a bridge is shaped so as to perfectly match the belly of an arch top instrument. Namely mandolins, viol family instruments and arch top guitars. I use special jigs for achieving this close fit.
Also keep in mind that these instruments tops are designed to resist the downward force of strings that use a tailpiece. Keep in mind also that a guitar with the bridge you describe, is designed to resist the upward pull of the strings on a glued on bridge. Or the forward torquing caused by the pull of the strings. I have seen these tops collapse at times.
are you trying to change a nylon string guitar to a steel string guitar? good luck that top is going to buckle.
No. it came strung with metal.
It's a flat top, and since I stripped it earlier (and am now rebuilding) I've reached inside. I do not know the terminology, but there is a wooden "plate" under the bridge position, and another where a tailpiece could attach.
I have ordered a short trapeze, but if structure becomes an issue, I have some very simple (hell, I could make one) claw type tailpieces to top mount, and then use a cigar box style bolt bridge.
Hi again James, I don't wish to be negative all the time but here's another issue to think about so that the project will come out well. Just a heads up from my experiences.
I gather that you are making this guitar into a lap steel and so having the high action normally used. If so all good, your main concern is collapsing or sagging of the top. However if you plan to use a tailpiece and have the bridge at its original height with a finger playable action, this will lead to other problems, lack of break angle over the saddles for one. Or maybe not.
James that plate under the bridge, the bridge plate is to stop the ball ends of the strings from cutting into the soft top, and it also acts as reinforcement.
Tim, as a matter of interest back in the early days in the U.K. I converted a nylon string guitar into a twelve string, and played it until I left for Aussie and left it behind.........I wonder?
Thx, Taff. No worries. Since I'm flying by the seat of my pants, I appreciate the help.
The funny thing about all these builds I'm doing is that I don't play guitar. So this is going to be steel only, no finger play
Taff, Back in 69/70 my step dad was a telephone installer for the PMG( later telecom then Telstra). among the many things he brought home from under peoples houses. was a guitar. i think it was a home made guitar and quite decently done. it was definitely not a commercial brand in fact there was no lable inside the guitar. was a size i would now call a parlour guitar. dad bought it to paint a picture on the back! anyway i inhereted it but not dad but someone not knowing put steel strings on it.
That was my first guitar repairsometime around 1979..lol the sound board was warped from the tension and me not knowing anything, removed the bridge sanded it till it sat flat, glued it back on and strung it with nylon strings.
played that giutar till it fell apart around 2005 ish... never did get the warp out just compensated for it..lol
A Trapeze style end piece, a flat wooded floating bridge and a 1"x1" square block under the bridge arealinking top to bottom will give it support and a bit more sustain without sacrificing all the hollow-body tone.
Hi, I'm not sure what guitar you tried that on, but I'm sure it will kill tone and volume by dampening the tops movement. If you try it James don't glue the post in, so it can be removed after testing.
My 65 MIJ ES330/Casino clone is a hollow body except for that small block and Gretsch has done this on many of their guitars over the years. It's like a Violin sustain Block.
Hollow body's are prone to feedback and loss of sustain because to top can vibrate too much, so the small block in the bridge area adds the support and lessens the vibration in a small enough way to still get hollow-body tone without a lot of feedback and adds a bit more sustain.
Hi Paul, now I see what you was referring to, and you are correct. I had a picture in my mined of a full acoustic guitar that relies more on top vibration to create sound. It's not designed to have that support so it will, and does, dampen the volume and tone.
I do not know the guitar to which you refer, I suspect it is an electric guitar. I could be wrong.
The "sound block" you spoke of in a violin (and all the viol family) is the sound post, and although it does add some support under treble side bridge leg area, it's function is to control the top vibration and tone of the instrument. It's too big a subject and this not the place to go into it, but it's to do with the much longer top vibration due to the sustained bowing action. A bit more valuable info for the CBG builder.........not, ha ha.