1968 D-18 Martin Specs

[Rob]

Trying to nail down all the correct specs and to confirm exact material used (possibly black ebony) to make a exact bridge for a 68 D-18 Martin. I have heard this is the guitar with-in one year one way or the other that Terry Clements played lead for Gordon Lightfoot with.If anyone has all the vital numbers like slot width which I think is 3/32inch slot depth (vital) length and compensation measurments as well as saddle material Iam sure it reallly help. Have some real excellent clos-ups saved off the net which show the saddle running the entire length of saddle and steep angel upto the string touch points.Thanks for any correct specs you can track down.anything that can be confirmed by factI here there were intonation problems with theses guitars possibly due to the supper thin saddle not allowing much ajustment.Heard they were discontinued sometime in 1969 so my guess is Clements was a 68 -Rob

[David Payne]

Rob,

I have emailed Martin before to get specifics on restoration work. Sometimes they don't know either because they made a lot of variants. In the past they have been quite helpful.

[e-mail]
[e-mail]

Dave

[Rob]

Thanks for this lead so far! Will drop that link a e-mail and see what comes back ! -nanccinut

[William F.Eden]

Check out this guys site if you havn't already [ Vintage Guitar info] he seems to know a lot about Martin Guitars Bill.""""""""

[Frank Ford]

All D-18s in that period had rosewood bridges, NOT ebony. It was a transitional time, and the switch was from Brazilian rosewood to Indian rosewood. I'm unaware of any particular change in saddle width, and the depth was variable. At that time, bridges were made in three thicknesses, 1/4. 5/16, 3/8, and the appropriate bridge was selected to accommodate the neck angle. Each bridge would have a different depth of saddle slot, of course.

Compensation was determined by the position of the bridge - saddles were not carved to achieve any degree of compensation. Any error in intonation is typically an error in placement of the bridge. That era was also a transitional time for nut and saddle material. Ivory, Micarta, ivory, and white plastic were used in the 1960s, although not in that order. The saddle was short, set in a blind-end routed slot as today's are. The "through-cut" saddle ended earlier in the 1960s.

[Rob]

What is a blind end slot Frank? Any idea the corrrect slot length. The close-up picks Ihave off the net seem to show the curve on the saddle ends starting back into the curve of the bridge wood (rosewood) itself. Is that a original slot?

[Frank Ford]

Yep, that's the original configuration. It's the same as a new Martin D-18.

[Rob]

Hi Frank got specs from Martin people and here is what they say on a 1968 D-18 Martin
First contrarry to what Iread on one web site the D-18WAS NEVER discontinued and still made today!
Bridge material -rosewood
max width - 1 1/16"
SLOT-3/32"
SLOT TOTAL LENGTH-which seemed short (only 2 -15/16") DOyou agress with that stat Frank?
Bridge height- determined by neck angle
max saddle hight clearing bridge -7/64"
distance low- E CENTER SLOT TO FRONT OF BRIDGE -5/16"
distance hight Eslot center to front of bridge 3/16"
Bridge total length -6"
string spacing 21/8"
saddle material -most likely ivory butmay have been plastic.
Any idea on slot depth Frank? Read the early post war Martins had in fact maple bridges which produced a much better sound and when rosewood was introduced sound quality went down hill.Has any one heard if this is fact as I have access to maple so sounds like the best wood to try and repoduce a Martin bridge.
What would a good starting point be for thickness Frank ....5/16" ?
Isthe end of the slot round as it appears Frank and the saddle itself a snug perfect round fit also.Any idea of a measrment from end of slt to drop-off angle where the saddle is contured to that angle by close-ups I have saved?
Thanks Frank forany of these few missing numbers to make things exact! -nanccinut

[Frank Ford]

I think you need to read more carefully. Just as Martin didn't discontinue D-18, they also didn't EVER use a maple bridge. They did, however, switch from maple to rosewood for the BRIDGE PLATE inside the guitar.

As the folks at Martin suggested, you make the bridge the appropriate thickness to suit the neck angle and achieve a reasonable amount of saddle sticking above the bridge. So, I can't recommend a "starting point" for the bridge height for just that reason - it is determined by neck angle.

Of course the saddle has round ends. The slot is made with a round router bit, so the saddle is made to fit. End fit isn't super critical, although the side-to-side fit should be quite precise for structural support. The measurements Martin gave are correct.

[Rob]

Thanks for that Frank. Imay have missed that bridge plate word but thought the artical found said bridge.as it was just two days ago I read it. Would Rosewood produce better sound transfer for the bridge itself as opposed to maple which I have in old blocks. Just wondered whether they use rosewood due to having a more exoctic finished appearance.Iknow the big Stweart McDonald supply store in Ohio sells blank 7inch X1-1/8 X 7/16 slats of rosewood for only $6.00 which would get the job done.Iam thinking Martin would do extensive testing and sound transfer being top priority and rosewood the hands down winner but who am I . Looks like the final thickness is the last thing to worry about Frank as you say. No one around here sells the stuff checking lumber yards but never checked florring companies or custom kitchen cupboard shops which may hit paydirt for me if you think rosewood is the only choice of the two.
Your expert advice, me being a Guild man not Martin is valued to no end by this Sunday afternoon plunker.Frank- nanccinut

[Bob Gaddis]

Just call the 1833 shop and buy a replacement bridge. They should have them in stock and possibly will have a regular size, and oversize and what they call a saddle-back bridge, depending on what you need to make it fit right.