Changing the bridge

Lombax · #1 01-07-2011, 07:19 PM

My string height is way too high. Part of the problem is that the G side of the adjustable bridge is jammed and wont screw anymore. I think even if I get it to move it still wont be enough. The strings are at about 12-15 mm. Is the better option to get a new bridge or try fixing the old one and shave off some from the top? How do I remove the bridge without dropping the sound post?

KUNGfuSHERIFF · #2 01-07-2011, 07:33 PM

I would lay the bass down on its' G string side, loosen the strings and pray. Once you get everything apart lubricate the adjuster threads with a small amount of candle wax. Irreversible modifications, if you have to ask what to do, should be left to professionals IMO.

Michael Case · #3 01-07-2011, 08:30 PM

Don't lay the bass on it's side and loosen the strings. Lay it on it's back, gravity might pull your sound post down if you lay the bass on it's side and loosen the strings.

JtheJazzMan · #4 01-07-2011, 11:55 PM

You can put a blanket on the top to stop the wood being scratched, and then use heavy weights to put pressure on the top in place of the bridge and strings. Id use around 15 -20 kgs.

Do it progressively, ie, loosen strings some, add one weight, loosen more etc.

More worryingly, I am concerned if you have 2 piece adjusters, you may have bottomed them out and the metal shaft of the adjuster is pressing into the top - denting it badly.

In this case, I also think you should take it to a luthier to fix it up. Sounds like there are a few things that need looking over.

Matt Ides · #5 01-08-2011, 05:32 AM

I have really tight adjusters and I loosened the D and G to raise them a bit, then did the same on the E and A side. All this was done with the bass on it's back. Next time I take it is I'll have the luthier soap/wax up the adjusters.

Eliminating some of the tension allowed them to turn.

KUNGfuSHERIFF · #6 01-08-2011, 06:02 AM

Quote:

Originally Posted by Michael Case

Don't lay the bass on it's side and loosen the strings. Lay it on it's back, gravity might pull your sound post down if you lay the bass on it's side and loosen the strings.

I don't understand this. With the bass laying down on the G side the post has nowhere to fall, as it is already as its lowest point in the box.

Ozmoid · #7 01-08-2011, 07:32 AM

Quote:

Originally Posted by KUNGfuSHERIFF

I don't understand this. With the bass laying down on the G side the post has nowhere to fall, as it is already as its lowest point in the box.

When you take tension off the top, it will move away from the back, creating potential for the post to "fall" further toward the G side.

Lombax · #8 01-08-2011, 08:38 AM

I appreciate all your suggestions. I really cant afford a luthier at this point as the bass is a CCB and I already have too much into it. I really want to get it playable and sound decent. Whats the best route to go ? fix adjust my bridge now or get a new bridge. How do I go about removing it safely?

Eric Hochberg · #9 01-08-2011, 08:44 AM

Has the string height always been that high or is it increasing on its own (which might mean a loose or warping neck)?

To remove the bridge, do what Jazzman says. If the threads are facing down, make sure they are not extending through the bottom of the feet into the top. A picture of your bridge before removal would really help here...

Michael Case · #10 01-08-2011, 09:34 AM

Quote:

Originally Posted by KUNGfuSHERIFF

I don't understand this. With the bass laying down on the G side the post has nowhere to fall, as it is already as its lowest point in the box.

Having the bass lying on it's back keeps it in an upright position, lying the bass on it's side it can slide towards the ribs/floor. I don't know about your bass, but mine has a bit to go from it's set position to the treble side ribs.

Lombax · #11 01-08-2011, 01:28 PM

The strings have always been that high. I was given bad advise that for slap bass you need high "action" but I now know that its not quite true. I recently played a colleagues bass and his action was very low. I couldn't believe the difference. Unfortunately my bridge is too high. I'll upload a few pics.

Lombax · #12 01-08-2011, 02:32 PM

Here is a photo of the current set up. I am going to go with Jazzmans technique for removing the bridge. You can see the stuck adjuster, its the farthest one in the pic. Its about 4 to 5 mm of room left but even that wont put my strings low enough. Is it easier to trim the base of the upper bridge or from the top of the bridge where the strings sit?

JtheJazzMan · #13 01-08-2011, 02:48 PM

Looks like you would have to remove a lot of wood off that bridge in order to get the action down.

But in the end I was once in a similar position, I had a chinese bass and the neck angle was too shallow. The bridge had to be cut down way to much in order to get the action low. It was a POS.

Im going to defer here, Im not sure what would be the best way to help without doing a lot of bass hacking.

dvh · #14 01-08-2011, 03:20 PM

If it's a plywood bass there is far less chance the soundpost will fall. I had the same issue with my DB. My guitarist friend is also a woodworker. We loosened the strings, took the bridge off, and he used his scroll saw to take about 1/4 inch off the top of the bridge being careful to maintain the original profile. Some further forming, sanding, notches for the strings, put it back on the bass, re-tuned the strings....

No unwanted consequences and it plays so much better... it's not rocket surgery

Andrew McGregor · #15 01-08-2011, 05:19 PM

Don't mess with the adjusters themselves except to unstick and lubricate them. Take a bit off the top of the bridge instead. Make sure the string slots are nice and smooth, no sharp edges to nick the windings of the strings.

Brent Nussey · #16 01-08-2011, 05:40 PM

I pretty strongly disagree with the above advice. If the top of the bridge is well cut, leave it alone, you probably will screw it up if you try to recut it. And there doesn't seem to be a whole lot of wood above the heart cutout to work with anyway. Looking at the picture, I can't be sure, but it looks like some wood may have been added in to the legs above the adjusters at some point. Anyway, the legs seem to be where you have the best spot to take out a little wood. If you're lucky, the adjusters are in there with the threads down (into the feet). Then you can take the bride off and carefully remove wood from the legs on a disc sander, being very careful to keep everything square and true, so that you take off the same amount on both legs and have a solid fit when you put everything back together. You may have to deepen the holes in the legs for the adjusters, depending on how much wood you take off. Looking at the picture, this seems like your best bet.

Good luck.

Edit: PS this is the process Lou DiLeone used to lower the string height on my bridge he'd made for my old Italian bass many years ago, when I switched from gut to metal strings. Of course he recut the top a little to accept the smaller diameter metal strings, but he preferred to take the height out at the adjuster spot I mentioned. Just so you know this advice comes from experience...

Lombax · #17 01-08-2011, 06:02 PM

That's good advice brent. I was waiting for someone to pick up on that. I wasn't sure if that would open up a can of worms though. I would have to redrill the legs. Its worth looking into tho. Thanks

forester · #18 01-08-2011, 06:06 PM

pencil the feet,legs etc, so it goes back together correctly.

ps
adjuster installed into foot trunion?

iiipopes · #19 01-08-2011, 06:29 PM

Use a drill press and a good vertical clamp to the press table so when you deepen the adjuster pins they are perfectly perpendicular.

Andrew McGregor · #20 01-08-2011, 07:08 PM

Quote:

Originally Posted by Brent Nussey

And there doesn't seem to be a whole lot of wood above the heart cutout to work with anyway.

Ah, good point. That makes a lot of difference... I was just thinking how I'd do it, and the top seems like less hassle. But there's not enough there to do it anyway.