Need specs for a flattened pyramid bridge

[Barbara Millikan]

I'm making up a blueprint from the 1889 Washburn parlor guitar I restored (Model 301) and since it didn't have the original bridge on it, I'm missing that information.

I'm assuming the Washburn bridge is close to the comparable period Martin in size, and that the flattened area is square, but I don't know how far out the center part goes before the trough, or how wide/deep the groove is there... or even if it is a groove and not a slot  Can anyone provide me with specs or pictures, or point me in the right direction to find them on line?

TIA Barbara Millikan.

[George Roberts]

Barbara,

I will get you exact measurements later today.  I'm headed out the door right now.

George

[George Roberts]

Barbara,

The bridges are all  very close to 6 and 1/4 inches long, almost 6 and 9/32.  The width varies from 0.900 to 0.960. 

The flat tops of the pyramids vary from 0.670 to 0.700 wide, and 0.808 to 0.830 long.

The angled faces of the pyramids are all about 1/8 inch.  The edge of the bridge at the base of the pyramids measures 3/32 to 1/8, but most of them are closer to the 1/8.

From the end of the bridge to the top, inner edge of the pyramid is always 7/8 inches.

From the end of the bridge to the edge of the center section is pretty uniformly 1 and 1/2 inches.

Saddles vary from 2 and 11/16 to 2 and 3/4 inches long.

The center section is always 3 and 3/16 inches long, and 0.350 to 0.405 thick.

Measurements were taken from the bridges of the two guitars in the pictures, from a guitar I am working on now, and from two bridges that have never been on a guitar.  The last two I bought years ago from a music shop.

If I've missed something you need, let me know.  Hope this helps.

George

[Barbara Millikan]

Thank you so much, George, for taking the time to post this. If I am understanding what I am seeing correctly, the sides of hollow trough between the pyramid and center section are parallel, and only appear to slant inward toward the front of the bridge because the front is slightly higher [0.405]  than the back side [0.35]. Is that correct?

Barbara

[George Roberts]

Hey Barbara,

Yes, you are correct.  In addition, the bridge thickness at the trough is 1/8 inch at the narrowest part of the trough.  Hope I haven't missed too many other measurements.

George

[George Roberts]

Barbara,

When going over this in the light of day, I find that I did miss another measurement.  The height of the center section of the bridge on the saddle side varies from 0.350 to 0.405.

The measurement I missed is the height on the pin side of the center section: that varies from 0.20 to 0.24.  It makes it a much steeper angle from front to back than you would have gotten with the 0.405 to 0.35 drop.

The first bridge pictured is a "Durkee Pat." bridge.  You would need that only if you had that unusual spacing of the bridge pins.  If that is the case, let me know and I can give you the additional measurements.

The second bridge pictured has a drop off in front of the saddle, and I haven't seen that before.

 

George