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Hi All,

I've come across a number of dread plans out there. I'm just wondering which (if any) plans most accurately reflect the original pre-war specs (thick neck, larger neck block, no popsicle brace, thinner soundhole brace, forward shifted bracing, etc)?

Any suggestions?

Thanks,

Erik

Thanks Filippo,

Yep, the whole definition of "pre-war" depends upon what year we're talking about and the various changes that Martin were making at the time. I'm hoping to find something close to a 1937 type spec with the features I mentioned in my original post.

As for the MacRostie plan you mention, can you confirm whether the plan found here: http://www.pilgrimsprojects.biz/guitar.html (Third plan from the bottom of the page titled: "6 String Acoustic Herringbone Guitar M5") is the same one as the StewMac MacRostie plan?

They look similar and the plans a are a little less expensive through that website than StewMac.

Thanks,

Erik

I have not seen a true prewar print yet but I can tell you the big differences are between the MacRostie plan and a true prewar . Lets look at a 1937 . The braces are going to be scalloped . The tone bars , and bridge plate will be inletting onto the X braces. Then the plate itself is smaller than the plate shown .
I think the MacRostie is based on a modern day Martin as this is the same plan Martin sells at GMC . Then on top of this difference you will see the Popsicle brace is not used and that the neck block will be 1 9/16 inch thick not the 1 5/16 . Also detail wise the herringbone is different and the zipper strip won't have the thin white divider between the squares .
The position of the X brace will be about 1 inch below the sound hole and the center of the 4 inch sound hole is 6 1/8 inch from the rim . Also the side support braces are a brown ribbon . This was saturated with hot hide glue and stuck about every 4 inch give or take . Later the ribbon was replace with a brown tape material . You can use a3/4 inch brown ribbon you can find at a store that sells material .
Also the rosette would be black and ivroid . Ivory was used on the nut and saddle . On the tail block there is a piece of wood glued vertical on the inside of the tail block . I have seen both spruce and rosewood used on the tail . Also there was a number of truss rods used . Square tube Ebony or tee rod . I am sure I missed something but this can get you started .

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I do have actual martin production pattern tracings for this era . If you do decide to go without the Popsicle brace , be sure to use the larger neck block to help the shear from the fretboard . I have had to do some serious repairs on a few modern Martins that had the Popsicle removed . That extra 1/4 inch helps support the load .

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I didn't realize the neck block was larger on the old Martins. Thanks for sharing that.

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Formerly known as Adaboy.......

Thanks for the feedback John and Todd. Thanks also for the link Todd.

In addition to the larger neckblock (which I just found out about a few days ago), I also understand that during the "no popsicle brace" period the #1 brace/shoulder brace was also thinner than the modern standard at 5/16" instead of 1/2" for the modern guitars.

How close is the side template on the MacRostie plan to a '37?
Cheers, Andy

It will get you close enough. I have seen variation between older martins that was about 1/4 inch. The molds were hand made and no CNC in the day . Also when things were glued up the environmental control isn't as it is today . Lets face it , your wood isn't from 1937 so keep it close and you will be fine. The BIGGIE is the tops bracing and neck block. Tucked braces . Smaller plate all the above mentioned .
GO for it and keep us posted .

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

What is exactly meant by "Tucked Braces"? Sitting under another brace sort of inter-locked?

Thanks.

-

Thanks. I found the UMGF a few weeks back so I've been doing a lot of catch up lately!

Pre war dreds are considered the top of the mark . There are so many things that set them apart from the modern dred . I documented a few 1937 D's and apart from what was noted above here are a few details .
The rosettes are wood fiber , maple and ivroid . They are different from the modern ABS rosettes . I need to check my notes but his is pretty close . The inner and outer rings are .015 ( b) .015( maple) .025 ( b) .015 ( maple ) .015 (b) The middle rosette is .015 ( b) .015( maple).030 (b) .040 ( ivroid) .025 ( b) .040 ( ivroid ) .030 ( b) .015 ( maple) .015 ( b)
The back binding has a .020 B/maple and the zigzag has no separators between the blocks. The top herringbone is angled a little different and is finer than todays .
That is the basics of the decorative aspects . The bridge is also slightly different than the modern through bridges . They are worth the effort to document and build.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Erik,
I can make you a copy of the plan that I use. I drew it from the many 1930's dreads that I have repaired. It has the top bracing layout and dimensions, but not all the build details.
Not trying to stir things up, but by 1933, every D-18 and D-28 that I have seen has all celluloid purflings and rosette, with the exception of the herringbone on the 28's. All lines are black and white celluloid, except for the wider 0.040" rosette strips, which are ivoroid.
The reinforcement strip on the tail block is maple, 1" wide by 0.09" thick.
The bridgeplate is 1 3/8" wide, and the back corners are mitered about 1/2" wide. That was done to facilitate tucking the bridgeplate under the X-braces. It also controls the stiffness at the bridge wings, which I have found to be a significant contributor to the sound.
AFAIK, there is no large format copier in my little town, so I have to make a trip to Kinko's in Knoxville or elsewhere to get it done. I have some other plans that I need some copies of, so I can do them all later this week.

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John

Wow John that's MIGHTY kind of you. I would have responded sooner, but I hadn't seen that this thread had resurfaced until just now.

If it's not too late, I will certainly take you up on that offer. I'll PM you to see what costs I can cover for copies, shipping, etc.

Thanks again,

Erik

I have received more requests than I could have imagined, but I believe I have made enough copies to fill them.
Instead of copying my bracing pattern I use for construction (which is worn and faded), I drew a new plan which includes the neck dimensions. Rather than confusing people with dimensions from many guitars (I have dozens of prewar dreadnought bracing dimensions), I decided to just do a rendition of one excellent example, which is a 1937 D-28. This is not a complete construction document, since I did not include plate thicknesses, back arching, or a side template. I also did not include any trim details like the rosette, binding, or purfling. IMHO, these are best left to the builder's discretion.
I will answer all the PM's tonight, with the shipping details.

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John

Hi John-

Is the 1937 D-28 you made the plan from, your guitar that was shown on Handmade Music (Lynn Dudenbostel episodes)? If so, then that was a sweet guitar. I just sent you a PM also.

Thanks-

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John Lewis
Wannabe builder owned by 2 crazy dachshunds

Thanks john!

It is. I have played quite a few 1937's, and IMHO, none have been clearly better. OTOH, my older pattern was taken from 1935 models, and is so similar that it makes no sense to differentiate between them, unless the properties of the topwood are taken into account. For instance, the 1937 is bright and clear, without a hint of muddiness that is typical of many prewar D-28's. I think it is because of the topwood itself, and how it was thicknessed, rather than any 'magic' in the bracing design.

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John

hi John,
I have heard that Henderson also uses a drawing made from a 37 for his dread bracing placement and dimensions. Is it the same as this example? does his differ in any way that you are aware of? just curious.

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"...you have to get over your strict adherence to your largely imagined notion of absolute perfection..."