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danb
Nov-16-2004, 4:16pm
Here's a neat detail you don't hear much mention of- the Gibson mandos (from the Loar range at least!) had the serial number written on the bottom in pencil. This is from my snakehead, spotted during a setup where I replaced the sagging original saddle with one of Darryl's reproductions.

Note also that "T" and "B" are written on the sides to remind the installer which side is treble, and which is bass!

http://www.mandolinarchive.com/images/71261_bridge_underside.jpg

danb
Nov-16-2004, 4:19pm
This photo isn't as good, but shows the underside of the bridge on the Schultz Loar (76547):

danb
Nov-16-2004, 4:21pm
note also that my snakehead ('23) has holes drilled all the way through for both posts, and the '24 Loar Doesn't. Hmm. The shiny bits on the bottom of my snake bridge are bits of finish that help me see exactly where this bridge started out.. they fit into the tiny little finish scars on the top

evanreilly
Nov-16-2004, 11:46pm
Let's see some more to these!!! A new detail!!!

troika
Nov-17-2004, 2:10am
The bottom of a bridge has to be the least-viewed most-accessible part of any mandolin. It's like a picture of the roof of your mouth.:D

danb
Nov-17-2004, 4:25am
Evan: that's my full collection of those photos!

Darryl Wolfe
Nov-17-2004, 7:20am
Yes ...this is an attribute of Gibsons from the period. #They do not always have the B & T marked though. #The lack of drill thru for the posts shows up usually only on F5's becaus the base is a touch higher. #They used something like a drill press with a stop. #When the profile on the bottom is cut, sometimes the high side of the base is not all the way thru. #The is something fishy about the Schultz bridge. #I haven't never seen one with the colored serial number. #I've not seen one with the hand cut marks on the middle relief nor one without the bandsaw type marks the the other pic has. #But I've been wrong before.

Charlie Derrington
Nov-17-2004, 7:40pm
I've never seen one with the colored number, either. Always in pencil and always with the bandsaw blade prints. But as it is with all old Gibsons, never say never.

Charlie

Dan Adams
Nov-21-2004, 7:57am
A little off the subject, but related. I just bought a twin to my 17 A Model that needs some work. It's all original but somebody striped the finish and then tried to refinish it with what looks like tung oil. The bridge is missing, along with a ferrel for one of the tuning pegs. Where can I get an original bridge, or a replica? What about the ferrel? Its being fixed to become playable, side seperations, but I'm not going to worry about the finish until I know it plays. Thanks is advance for the information. Dan

MANDOLINMYSTER
Nov-29-2004, 12:57pm
Heres the "Pat applied for" stamp on a 1921 bridge

Darryl Wolfe
Nov-29-2004, 1:01pm
Heres the "Pat applied for" stamp on a 1921 bridge
Good subject...I bought the bottom and the top of this deal separately....I didn't know until much later that they went together as the real prototype adjustable bridge

MANDOLINMYSTER
Nov-29-2004, 4:04pm
Check this out, just noticed this for the first time, a patent date "Pat'd Jan 18- 21" on the TOP of a 21 bridge base/with aluminum top

MANDOLINMYSTER
Nov-29-2004, 4:09pm
So as not to be confused, I have 2 21 aluminum topped bridges, one with the "PAT'D APPLIED FOR" on the side, and the other with the "PAT'D JAN 18-21" on the top of the base, so look under those saddles! http://www.mandolincafe.net/iB_html/non-cgi/emoticons/biggrin.gif

mandroid
Dec-19-2004, 11:00pm
1)thumb wheels above the top of MANDOLINMYSTER 's photo stirs my 'why is it like that?' reflex...howcomesit?
2)so, top profiles off duplicating tooling are standardized enough that bandsawing the arch into the bottom of the bridges is good enough following a pattern jig for that part too?
match sanding just for the small numbers of tooling, jig and fixtureless folks
http://www.mandolincafe.net/iB_html/non-cgi/emoticons/rock.gif

danb
Dec-20-2004, 5:37am
I've always assumed the 2-wheel design was only on the prototypes because the saddles were a bit too thin. I figured it would help keep it firmly in place with a locking nut system.

I had one of those prototype flat adjustible aluminum saddles, and it sagged quite badly.. Many years ago, Evan Reilly supplied me with a machined loar-size aluminum saddle (the flattened T-shaped sort, like the top of an ebony Loar bridge) that worked quite well. Somewhere I still have the precise measurements of that saddle on a machinist's diagram.

There was no real way to tell the difference between them for me, except that the new one was obviously part of a better set-up.. In fact, I never really felt as though I fully understood much difference on the wood/aluminum saddles either! That particular A model was nothing special so harder to judge subtle differences on

mandroid
Dec-21-2004, 5:18pm
DanB:
As I have an #A which I got 20 years ago 1921 vintage, with aluminum bridge top, my curiosity arose, {its still fine,sagless,some additional thickness between the thumbwheels, perhaps this is revised design. in adjusted height studs ends just slightly protrudes above it, and as threaded material is an alloy, polishes nicely with use.
Newer aluminum alloys,and heat treatment/ tempering, #ought to look the same, but be very much stronger.

tone described acoustic with Electric-y sound says Niles H

[by contrast; newer [lebeda] #bridge shows rusty ends of steel material]
http://www.mandolincafe.net/iB_html/non-cgi/emoticons/wink.gif
translating the dimensions to a die for extrusion of aluminum, would be the way to go.
http://www.mandolincafe.net/iB_html/non-cgi/emoticons/mandosmiley.gif

evanreilly
Dec-21-2004, 6:46pm
One of the volumes of The F-5 Journal has a schematic of the Loar-era ebony saddle. I don't recall if the fellow I had machine the aluminum saddles used those specs. I have used those specs to have other saddles made for me, tho.