Method for Pinning Archtop Bridge

[Robbie Collins]

Is there a straight forward method for marking and drilling holes on the soundboard and bridge bottom of an archtop bridge? Also, can you guys recommend a material for the pins? I'm guessing cut off finishing nails. Thanks.

[Paul Verticchio]

Hi Robbie.

There's no need to drill.

Simply mark the bridge's location on the top of the guitar after it's base has been profiled to the top of the instrument and it's been positioned for proper intonation. I use low tack masking tape to mark the location.

Then, remove the bridge, drill a 1/16" diameter hole 1/16" deep on the underside of each 'leg' of the bridge.

Cut the tips off of two brads (small nails). They should be 3/32" long. Perfect matching is not required. What you want is 1/32" of the brad's sharp point exposed.

CA or epoxy the 'pins' into the holes you drilled...sharp points facing toward the top of the guitar. 

Let the glue cure, clean up around the brads, re-align the bridge to your tape marks, push down on it so the pins penetrate the top of the guitar and, as Hesh says "Bob's your uncle." Boy, that Bob sure has a lot of nieces & nephews. What a rounder ;)

Hope that helps.

Best regards,

Paul

[LARRY KLOSE]

I'm not getting this.  I have a couple of archtops, two mandolins and have had several others of each in the past.  They didn't come from the maker pinned--the bridges all float.  

Why would it be a good idea to pin the bridge to the top?  Every one of my instruments has needed adjustment of the bridge position to correct intonation in order to accomodate variables like changes in height, different strings and different setups.  If the bridge is pinned, it's difficult to make any adjustments.  Setting intonation isn't that hard with the bridge floating, either.

Is it different with some applications than others?

Larry

[Mike Kolb]

I would normally agree, Larry.... but (having said that) I have one customer who plays an old Kalamazoo archtop and a mandolin and, man, he plays hard!

His flailing right-hand style is such that he tends to shove bridges all over the place.  So, at least for for him, the pointed tips on the underside of the bridge work well. 

[LARRY KLOSE]

Thanks!  I learn something every day from this forum.

Larry

[Robbie Collins]

Thanks, Paul. I was over-thinking, which I do a lot. I was worried about parallax, but with 1/32" exposed it couldn't be off much.

Larry, the customer asked for it and my experience with my Gretsch 6120 Horton Heat (which came pinned from the factory) is that it's a godsend when changing strings and, as Mike said, when you have a someone with a heavy right hand. These guitars both have TOM bridges so can be adjusted, unlike a conventionally carved arch-top bridge.

[Jeff Highland]

I do it a bit differently

I only pin on TOM equipped bridges.

I set up the position, checking for intonation and alignment and tape the bridge base ends in that position

Pull strings and bridge top

Drill 2 holes just inside height wheel, though bridge base into top sized to a pop rivet pin.

Glue pin into soundboard with CA 1/8" protruding.

Bridge base sits down onto pin. I don't like the idea of pins fixed into the bridge base, that is top damage  waiting to happen.

[Robbie Collins]

My Gretsch's pins are in the soundboard too.

[Ned Knepp]

I don't have trouble with my bridges moving around when I play but I got a mandolin that came with very fine grit sand paper glued to the feet of the bridge. It isn't something I would have though of but it seemed to worked pretty well and it hadn't done any great damage to the finish which I believe was because the bridge didn't move around. 

[Ian Pender]

I've used rosin in a similar manner to prevent slipping. Still, some people really whomp on their guitars.