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Hello all,

This is kind of long.....sorry wanted to explain myself well!

I have finished all the woodworking on my acoustic/electric project. YEA! I am at the final steps.....finishing, bridge placement & attachement, and set up. The finishing will be shellac and satin rockhard with no filler......that was an easy decision compaired to my last and final measurement that I have to make.

Note I have done some searching here and not found my exact questions.... I hope not to repeatly ask what might be the obvious to you guys so here goes!

I have made everything except the fretboard and bridge on this (my first) build. The fretboard is a fender scale one from stewmac. The bridge is a premade Ovation style from allparts. It has a preslotted saddle (and itis vertically angled back as well).

The last and final thing is to get the placement of the bridge down pat so the intonation will be within range to tweak with files with the existing 3/32" wide saddle during setup. This step terrifies me! I have been nervous before with all the other steps but this is kind of a final test so to speak of my processes that I have learned. I went to the stewmac site and used their fret calculator with a fender scale (25.5) and had the acoustic guitar sellected (drop down box) prior to it calculating. The answer it spits is below:

Treble "E" 25.588" (±0.030")

Bass "E" 25.714" (±0.030")

I understand that this measurement is taken from the breakpoint of the string at the nut to the break point of the string at the saddle. I used these measurements on my test mule that I built and everything played sharp. I used the same bridge with the test mule and figued because the saddle was angled(vertically)and after I filed it down to get the correct action, I moved the break point towards the neck.....therefore sharp everywhere. Tracy and I talked about this a while back and he recommended to add an extra 1/32" to my measurements to compensate for this and because the human ear has a harder time hearing flat out of tune notes rather than sharp.

Finally for the first question......do these measurements above + adding the 1/32" to them check out with you guys? I really do not want to glue this down, go through all the final work and have to pull it up, refinish and reglue. (that being said I would learn a great deal from that but right now I just want to play my first one!!!). These measurements and calculator are the only ones I have found on the net that give me any starting place for bridge placement. I have a strat that I can measure against but it is a trure electric guitar and the strings and action will be different so I was reluctant to use that as a strict template.

The second issue is glueing procedure. As stated above I will be using schellac and rockhard varnish (satin) as a finish with no filler. The bridge I am using has predrilled screw holes that I am going to use to attach it to the body (and use for reference once I get the above measurements down pat). Let me say this is not an acoustic hollow body.....it is like the Anderson crowduster guitar.....chambered with a solid block running from neck to bridge. My procedure is (as of now ) as follows:

I was going to get the bridge placed, drill the matching holes in the top for the screws so the bridge is now set, finish the guitar, mask bridge area, set the bridge back using the screw holes as reference, scribe outline, come in 1/32" in from that line, cut out area from the tape, use dremmal tool with downward spiral bit to remove finish, clean up with sand paper, and glue & screw it down.

The second question......Does the above procedure hole water for a novice and the type of finish I am doing. The only reason I picked this is because I think I would have a hard time leveling and getting an even finish if I put the bridge on first then finish.....But I am asking your advice here!

Lastly, how do you guys go about setting the dremmel to only cut the finish? when performing the removal? Do you finish a scrap with the same number of coats and use trial and error to get it right prior to going to the guitar? .....or do you measure the finish thickness some other way?

So 3 questions in a book of a poast! Sorry to be so long winded but I wanted to make sure you all knew were I was comming from.

Thanks a million!!!

Matthew

Matthew,
I understand what you are doing with the exception of screwing down the bridge. you know what they say.... a picture is worth a thousand words...

You have the routine down pat. As far as the final cleanup of the finish, this is mainly a trial and error as far as setting the dremel to proper thickness. You can always test the depth on a scrap piece of wood and then estimate if you are taking off enough/too much. If your top is highly curved, this setting may have to be altered until you have it right. I have found that I can usually score a line with my exacto knife and then peel off the unwanted finish with not too much effort. You may consider this as well. Being careful is extremely important.. take little bites with the chisel.

If you set the saddle at the same point as your fender that has the same scale, you will come out perfect (assuming the intonation on the fender is correct also).

By the way, I am working on something similar, but mine is a hollow body. It will debut at the Miami Guitar show in April.

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Reguards,

Ken H

I cheat when it comes to placing the bridge.

I rig up a jig as a tailpiece and slide the bridge into place to set the intonation to within a cent or two, mark and glue, then fine tune on the bone saddle.

VERY simple, but it works!!

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Thank you for the feedback gentlemen. I tried to find the picture from the allparts site where I got the bridge but to my horror I think they stopped selling the thing! Well there are two counter sunk holes on the back side of the bridge which I will use to put screws through then put black dots to hide the screws when done.

I will "try" the dremmal idea on the test piece I intend to put the same finish on. I will see if I can get the measurement down prior to using it on the real thing.

I will check the measurements I mention in my first post against my fender electric to see if they match.

Martin,
I have seen either your pictures (or someone elses)here or at the mimf of the tail piece you speak of. My end pin is not on center due to the "design" of the electronicts I am using. But that being said I really like the idea and will try to make it work to get pretty much exact placement of the bridge. Thanks for reminding me of this jig!

Again thanks for the comments!
Matthew

Glad to be of help.

A a teacher (highschool) i'm always aware that someone who has JUST worked out something is ofter better at teaching it to a noob than and experienced, qualified person.

One of the reasonds I LOVE this place, there are so many "just a few steps ahead" folks to help out!!

mind you, the pros are great too!!

That was me BTW!!

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