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Hello All,

I went out to my shop early this morning, in hopes to permanently attach the neck to the body,
and get started on shaping the nut and saddle. (I had glued up the bridge yesterday afternoon.)
However, when I removed the clamps and did a quick check on the placement of the bridge,
I found that it had moved slightly in the opposite direction of the sound hole, which increased the
string length by .030". This increase is only in relation to the 12th fret. The distance from the nut
to the 12th fret has not changed.

The pictures below show how I set it up with the “Saddlematic” I purchased from StewMac.

One of the pictures shows, what I thought, was a pretty good idea. I made (for the lack of a
better word) a bridge holder. Once I had the bridge in the perfect position, I clamped the bridge
holder very lightly to the body of the guitar. I was then able to remove the “Saddlematic”, and
glue up, and clamp the bridge. It should have worked perfectly, but, some how it did move
somewhere along the procedure. Maybe, its nothing to worry about!

Anyway, before I go any further, I thought, I would put it before the board of well experienced
OLF guitar builders, and see what you all think about it.

Oh yeah, the last two pictures show the final polished True-Oil finish on the body.

Thanks for looking!

Robert



The first thing I did, was check the bridge placement






the following is a re-enactment from yesterday
















Here's the polished True-Oil Finish on the body.










Thanks again, Everyone

_________________
Everything has beauty, But, not everyone see's it!

G'day Robert,
               First of all , I really like that true oil finish . A lot of finishes you see look like the guitar has been dipped in plastic .

Although your bridge jig looks good , I wouldn't trust it again as it has proven it can let you down . A better method is to insert removable pins through the saddle slot . That way, it can't move , and it's simple

_________________
CRAIG LAWRENCE of AUSTRALIA
_____________________________________________

If the intonation isn't good,I would consider making an ebony 'filler' piece ( or whatever the bridge is made from) the exact size of the saddle slot, glue that filler piece into the bridge, level it to the top of the bridge, and re-route the saddle slot to where the intonation is correct.

I`m pretty sure this is the reason some of us route the saddle slot after the bridge is installed.
                        James

_________________
James W Bolan
Nashville Tennessee

if you are unable to get enough intonation adjustment with the width of the existing saddle slot, i would second hesh's suggestion of widening the slot and fitting a wider than normal saddle, something which i like anyway. and his offer to lend you his jig is most generous.

to avoid such events, i use pin hole locating pins to prevent movement, and i usually don't route the slot until the bridge is glued on, and used individually compensated saddles. a bit more work, but i feel the results are worth it.

if you are using mechanical clamps, as mentioned in previous post, a screw type has less tendency to move the clamped object, but i prefer vacuum over clamps anyday.

Nicely build dred there, a VERY well done. You have really enhanced the beautiful hog grain.

A very clean build for a first!!!

BTW, the filling of the saddle slot and re-routing is a great option. I did that with my rightie Avalon a week ago (now a beautifully intonated lefty )

Hey Robert,

The guitar is looking good.

I too think that you will be fine with the intonation setup with a 0.030" sift back on the bridge.

And if you find that it plays sharp you may have to move the saddle location. Although I like the idea Jack gave of filling the slot and re-routing, you would be moving the saddle more to the front of the bridge and if there is not enough material between the front of the bridge and the inside of the slot, the pressure on the saddle from the strings can sometimes crack the bridge. So if you find that you can't get the break points far enough forward you will have to take the bridge off and re-set it.

Something that you will want to watch out for (a small criticism if you don't mind) is never to clamp to the body on the inside like this.



It doesn't take much pressure to crack that back or top and clamping like this is a good way to crack that new guitar of yours. If you have to clamp to the body, make sure that the clamps are near the edge where the liners and the side are. There is more strength there than in the area you've clamped to above.

Like Craig mentioned, you want to place the bridge than use some sort of locater pin either through the saddle slot or two of the bridge pin holes so that the bridge won't move when you've clamped it down.

I was trying to find a picture for you but couldn't easily find one in the archives. Take a look here for a good detailed description JJ gives (about 2/3 down the thread) for gluing on his bridges.

Keep it up Robert, that box will be singing soon.

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"There's really no wrong way, as long as the results are what's desired." Charles Fox

"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson

[quote=Rod True]Keep it up Robert, that box will be singing soon.[/quote]


Too right. These Stewmac kits have an amazing tone when strung up.

Rod,
If I understand the problem correctly, the bridge with the pre-cut slot, is glued in error,approx. .030 toward the end block? If that's correct, wouldn't the widening of the saddle slot as Hesh suggests, also weaken the front side of the bridge at least as much as filling/recutting the slot?. If the existing slot is .30 too long, it's not going to play sharp is it? If the bridge were removed and re-glued, wouldn't (that) require an over-sized bridge (.30 larger toward the tail-block) to cover the un-finished area that was under the original bridge?

[QUOTE=jack] Rod,
If I understand the problem correctly, the bridge with the pre-cut slot, is glued in error,approx. .030 toward the end block? If that's correct, wouldn't the widening of the saddle slot as Hesh suggests, also weaken the front side of the bridge at least as much as filling/recutting the slot?. If the existing slot is .30 too long, it's not going to play sharp is it? If the bridge were removed and re-glued, wouldn't (that) require an over-sized bridge (.30 larger toward the tail-block) to cover the un-finished area that was under the original bridge? [/QUOTE]

I think we are saying the same thing as to the front of the bridge and slot regarding the strength of the bridge.

I would think it would be easier for Robert to redo the tru-oil rather than make a new bridge.

It's something that I always forget when setting up the intonation. Flat/Sharp which way to move the break point of the saddle. I wrote it on the wall in the shop but I'm not there right now. Isn't it flat-forward, sharp-back??

So if when Robert strings it up and starts setting the intonation, if the guitar plays sharp, he would have to move the break point on the saddle back.

Someone help me out here please.

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My Facebook Guitar Page

"There's really no wrong way, as long as the results are what's desired." Charles Fox

"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson

Well, as always, you all are so prompt to respond to my posts! Thanks to All!

Hesh, as usual, you are quick on draw! Thanks for the positive comments, coming from you, that
really means a lot! Because, your guitars are exquisite! Also, thanks for the offer to let me borrow
your saddle jig. But, perhaps that won’t be necessary, as you have said I should give intonation a
try first. I should say, that I was aware of the cam clamp pull, and, I made the allowance for that
every time I did the final clamping. The bridge holder was cut so close to the size of the bridge,
that there was zero play when the bridge was placed in the notch of the bridge holder.
And, I did not remove the “Saddlematic” until I was absolutely sure that the bridge holder was stable, and
that the bridge was snuggly in place. That’s what had me a little stumped.

Oh Yeah! Could I get the 5 clapping hands emoticons in advance? I, I, I, promise I’ll keep hurrying!

Craig, G’day to you too! Excellent advise on using removable pins!

Jack, I think that is a very good method, and I’m going to write that one down.
Hopefully, I won’t have to do that this time.

Michael, you got me interested! you mentioned, vacuum over clamps. How do you do that?


Sam, good to hear from you, and thank you for your complements!
So, you did a stewMac kit too?

Rod, you can, and should criticize me all you want! I may not have said this, but, I have a lot of
respect for you, and not just when it comes to guitar building.
I would like to say though, that the pressure applied by the cam clamps to the top and back of the guitar
was no more than what could be considered, a firm grasp with your thumb and middle finger.
However, in the future, I could easily do it differently by using masking tape.
Also, you and several others have suggested the bridge pin holes to secure the bridge. I will be
doing it that way the next time, you can count on it!

Todd, I see you agree with everyone else on this, and gonna do what you and Hesh have said.
I’m gonna string her and see what happens!
BTW, are you going to go to the Mid-Atlantic Gathering?

Thanks again, I will now go back to the shop, and get started back on that geetar!

Robert

_________________
Everything has beauty, But, not everyone see's it!

perhasps i wasn't too clear. by "over", i meant "instead of".

you can see a vacuum bridge clamp on lmi's site. basically just a small rectangular frame with a membrane on one side and sealing gasket on the other. apply glue, locate bridge, place clamp over the bridge, apply vacuum. absolutely no tendency to move the bridge, very even clamping over the whole bridge surface regardless of shape or curvature, no fiddling with cauls, though pin hole dowels should still be used, and very quick which greatly enables the use of hhg. rather simple and foolproof.

my version is shop made using scrap birch ply and membrane rather than the rather expensive retail sort. works just as well though.

0.030" is just under 1/32.
If you planned your compensation/intonnation carefully (to be at the center of the saddle), you will be able to adjust for it.
Just do not make the top of your saddle round, but slightly skewed toward the front. The G string, which needs more compensation, will probably be at the center.
Good luck!

Robert,

My first guitar was a Stewmac dreadnought, EIR back and sides, spruce top. I intended to build a few more kits before trying a scratch build, but my second instrument is a.....scratch build..go figure...

I read the Stewmac reviews, most people spoke of the amazing tone these guitar produced when set up nicely. I half believed it, mostly being grateful for the currency rate, because a Stewmac Kit is about half the price of a kit bought in the UK.

Well, a year later, and my first guitar is absolutely wonderful in sound and a joy to play (I play it almost daily) I'm still faffing about with action and will eventually settle for something I like.

[QUOTE=Hesh1956] Sam's right Stew-Mac kit guitars, at least the d****n****t that I have experience with, sound great![/quote]

hahaha, sorry, I cannot go back and edit my d****n***t post!!

I've been playing the git for eighteen years, and feel incredibly lucky to have a great sounding guitar at long last.

Michael, I will be checking out the vacuum clamp at LMI, but, I’m more interested in seeing yours.
Maybe, one day in the future, if you have the time, you could post some pictures of it!

Alain, interesting that you should bring that up! I was thinking about this very same thing
yesterday afternoon. I should mention the setup of the “Saddlematic” by StewMac. They give a
compensation of 5/32" for the “Bass E” string, and 1/16" for the “Treble E” string.
These measurements are taken from the side of the block furthest from the 12th fret, and measured to the
pins that are secured in the block. Then you position the bridge, so that the pins are touching the
inside of the slot of the bridge closest to the sound hole. If you copy paste the following link, it
shows in detail how this is done. The question is, did StewMac consider the center of the saddle
when they configured the compensation?

http://www.stewmac.com/shop/Tools/Special_tools_for:_Bridges /1/Saddlematic/Instructions/I-4462.html#details

Sam, and Hesh, I’m certainly glad to hear you say such wonderful things about the StewMac kit!
I tell you, I just can’t wait to hear this guitar sing! I’m so close to having it done, and I’m very
excited too! I have to keep reminding myself to slow down, cause’ I don’t want to mess it up!
I really wanted to have it finished when I bring it to the OLF gathering, but, I’m going to take my time and do right!

Thanks again to All

Robert

_________________
Everything has beauty, But, not everyone see's it!

Hello All,

I got to thinking about what I’d said in my last post. So, I went back to read the instructions again
for the StewMac “Saddlematic”. Turns out StewMac did consider the center of the saddle when
configuring the compensation.

Sorry ‘bout that!

Robert

_________________
Everything has beauty, But, not everyone see's it!

One thing that has not been mentioned is that when the bridge shifted, it likely had one edge that lifted up over your finish resulting in less than an optimal fit of the bottom of the bridge to the top where you scraped off the finish. If your finish has any thickness to speak off, then your bridge may not be well glued to the top now.

Did you use hot hide glue to attach the bridge? I would suggest heating the bridge and shifting it back to the proper position. Reheating it is no big deal especially since it was freshly glued. I had this happen once and it really emphasized the value of positioning pins.

[QUOTE=robertandsons] The question is, did StewMac consider the center of the saddle
when they configured the compensation?
Robert[/QUOTE]

Lets see:
0.156 and 0.062 make for 0.109 at the front of the saddel in the middle (between D and G strings).
The saddle is 3/32 thick = 0.09375"
The center is at 0.0469"
The compensation at the center is then 0.109+0.0469= 0.156"
Cumpiano recommends 0.15" and this is what I do also.
Your bridge is off by 0.03"
I would say you are OK but your saddel top will be like this   D instead of this O

[QUOTE=BarryDaniels] One thing that has not been mentioned is that when the bridge shifted, it likely had one edge that lifted up over your finish resulting in less than an optimal fit of the bottom of the bridge to the top where you scraped off the finish. If your finish has any thickness to speak off, then your bridge may not be well glued to the top now. [/QUOTE]

Barry brings up a good point. However, your Tru-oil finish is probably whisper thin. If you didn't scrape down into the spruce, but only removed the finish, that couple of mils of finish thickness shouldn't have any effect on the glue joint. Lots of builders scrape (or rout) off the finish a smidge inward from the edge of the bridge outline and glue the bridge on overlapping that little bit of finish around the edge. Some rout a very shallow rabbet around the edge of the underside of the bridge, but many don't do this and don't have any problems. Again, if your finish is very thin and you've been careful to remove only finish, not wood, when scraping, the glue joint should be fine.

_________________
Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

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