M-85 measurement/placement help

drbassman · June 21, 2009, 06:33:16 AM

OK, I'm ready to drill some holes and I'm not quite sure the best way to measure for placement of this Guild bridge. The saddle channels are offset already and I'm thinking I need to have my bridge measurement point somewhere in the middle of the channels to allow for intonation adjustments.

Essentially, my scale is 30.25" so any suggestions on how to handle this odd bridge?

PS: Happy Father's Day! Working on my basses is my gift to myself!!!

Rob · June 21, 2009, 10:16:20 AM

Hey Doc!
A real world meaurement is best, but those bridges had a lot of slop (or sorry lattitiude)from the factory.
Some didn't intonate on the G if my memory is accurate.
(they need to go closer to the neck but were limited by the slot). So I'd go slightly forward of center.
PS I have some sloted rosewood for saddles if you want it send me sign.

Dave W · June 21, 2009, 04:09:59 PM

I wouldn't put it in the middle of saddle travel, you would just be depriving yourself of adjustment room you might need. The correct compensated distance can never be less than the uncompensated scale length.

Guild short scales were actually 30.75" (even though they usually published it as 30.5) so you don't want to base it on what the factory did.

drbassman · June 22, 2009, 05:46:03 AM

Quote from: Dave W on June 21, 2009, 04:09:59 PM
I wouldn't put it in the middle of saddle travel, you would just be depriving yourself of adjustment room you might need. The correct compensated distance can never be less than the uncompensated scale length.

Guild short scales were actually 30.75" (even though they usually published it as 30.5) so you don't want to base it on what the factory did.

Yep, I'm using my own 30.25"scale (it's what my Stew-Mac equipment gives me with their slotting tools). Can you explain ehat you mean by your "compensated vs. uncompensated length? comment? I'm not clear what you're actually saying.

Dave W · June 22, 2009, 07:51:05 AM

I mean, whatever the actual mathematical scale length is -- twice the nut to 12th fret distance -- your saddles will never need to be closer than that. I.e. if you have an true scale length of 30.25 in. before compenation, you'll never need to adjust a saddle forward to 30.15 in. It will always be a minimum of 30.25. The point of contact on the saddle never needs to be closer than that.

Hope that makes sense.

drbassman · June 22, 2009, 09:12:21 AM

Quote from: Dave W on June 22, 2009, 07:51:05 AM
I mean, whatever the actual mathematical scale length is -- twice the nut to 12th fret distance -- your saddles will never need to be closer than that. I.e. if you have an true scale length of 30.25 in. before compenation, you'll never need to adjust a saddle forward to 30.15 in. It will always be a minimum of 30.25. The point of contact on the saddle never needs to be closer than that.

Hope that makes sense.

Makes sense. I checked the measurements on another bass I made with the same 30.25" scale and the G is right at 30.25" and the E is at 30.50" with the A and D in between. Fortunately, there's almost 1 inch of travel for the saddles on the Guild bridge. So, making sure I have adjustment room beyond 30.25" is the way to go, right?

Dave W · June 22, 2009, 11:36:31 AM

Quote from: drbassman on June 22, 2009, 09:12:21 AM
Makes sense. I checked the measurements on another bass I made with the same 30.25" scale and the G is right at 30.25" and the E is at 30.50" with the A and D in between. Fortunately, there's almost 1 inch of travel for the saddles on the Guild bridge. So, making sure I have adjustment room beyond 30.25" is the way to go, right?

I need to rethink this. That's what I would do in most cases, but maybe not in this case, because the bridge saddle positions are already staggered, like compensation. You might wind up with the larger strings too far back even when the saddles are farthest forward. I'm not sure, since I haven't had a Guild for almost 10 years and I can't tell from your bridge photo how far the positions are staggered. Looks like maybe there's about 3/8" stagger from one side to other.

Sorry, I shouldn't have opened my mouth before considering that you weren't talking about a bridge where the saddles can all travel to the same point.

Rob · June 22, 2009, 05:53:50 PM

Oops! I wasn't worried about the saddles as they can adjust forward and back. . . unless it is one of the mystery weird things that I'd seen in the past, where the G couldn;t go far enough forward.

My hunch would be to center the mounting slots as you have identified them and then attach the bridge.
Rob

I made some crude prototypes once to reach across the top of the bridge by about 3/16". I'm sort of siding with Dave's comment about the offsets already in place.

Highlander · June 23, 2009, 04:40:54 PM

My SG had an intonation issue with the low E which I resolved by reversing the saddle...

Yes, I know... another refin needed...

Nearly forgot, modded the "Gibson" Bigsby to place the string posts uppermost (1/2 turn)- used to be a real pig to re-string...

drbassman · June 24, 2009, 08:51:38 AM

I think keeping the actual scale measurement close to the middle of the compensated slots on this bridge will give me enogh room in both directions.

Pilgrim · June 24, 2009, 10:34:22 AM

Perhaps measure the placement on other instruments you have and see what the most common placement is?

drbassman · June 24, 2009, 10:55:29 AM

Quote from: Pilgrim on June 24, 2009, 10:34:22 AM
Perhaps measure the placement on other instruments you have and see what the most common placement is?

I've done that and it does help. This bridge is just so different I wanted to make sure I wasn't missing anything!

Rob · June 24, 2009, 06:14:59 PM

Quote from: drbassman on June 24, 2009, 08:51:38 AM
I think keeping the actual scale measurement close to the middle of the compensated slots on this bridge will give me enogh room in both directions.

That's what I was trying to say

chromium · June 24, 2009, 08:07:47 PM

Quote from: ckngumbo on June 21, 2009, 10:16:20 AM
Some didn't intonate on the G if my memory is accurate.
(they need to go closer to the neck but were limited by the slot). So I'd go slightly forward of center.

My JS-II had that same issue. The G saddle was at its bounds, and just needed a touch more travel in order to intonate properly. When I installed the "Marko" bridge, I used the original anchor screw holes in the body as a guide, and just scooted it up towards the neck slightly (~5mm or so) to give myself more travel on the G string's saddle.

(note- this bridge mounts to a sustain block, pictured below)

I'm happy to provide any measurements, if you need 'em.

drbassman · June 24, 2009, 08:27:10 PM

Quote from: chromium on June 24, 2009, 08:07:47 PM
I'm happy to provide any measurements, if you need 'em.

Thanks! Do me a favor. Post your scale measurement and where your bridge is mounted. Maybe the distance from the nut to the top edge of the bridge?