Double Bass Buying a pair of bridges

[coyote1]

They are inexpensive, but apparently solid maple so they should be fine. As some of you have seen, the bridge that came with my bass (and by all accounts, is the original) was set up backwards. See attached image. So the plan is to a) loosen the strings enough to get one of the new bridges into place, so I don't have to fuss over the sound post, b) shape the other new bridge, using the original as a guide but doing it correctly, and then c) slide the new bridge into place.

From there I will shape the second bridge to roughly what it should be and then put it in storage for future use. They are not adjustable, so if needed I will swap them in and out til I feel I've optimized the setup. I did not go with adjustable because the top being laminate, I want as clear a transmission of string vibration to top as possible to maximize the sound.

 

[AGCurry]

Due to the photo's perspective, it's hard to tell for sure, but I'm not certain that bridge is backwards; it mainly looks warped to me.

Perhaps more importantly, I've not heard of fitting a bridge by using another bridge as a template.

But I wish you success!

 

[coyote1]

Nope, not warped. That is the photo perspective. The side you're not seeing is essentially flat. In either event, it's in need of replacement.

But I can't imagine NOT using the previous bridge as a template! It will allow me to get a quick, uhhh, footing on the footings. Get the correct shape quickly, and likely only need micro-adjustments from there. And the top of the bridge is pretty well matched to the shape of the fingerboard. It's just a tad too high.

 

[Don Hergert]

If I understand your proposed process, it's going to be hard to properly shape the bridge feet to the top of your DB while another bridge is sitting in the correct bridge position.

Ideally the top is used as the template for the feet, not another bridge's feet -- sandpaper is securely attached to the top and the feet are sanded up and down against the top to fit that curve. Masking is applied to the top to protect it from scratches, etc. Also, the arch of the bridge needs to match the arch of the fingerboard and the end of the fingerboard can be used to create that template, so that also will need that space on the top.

Fitting a new bridge is not as simple as it looks. The new bridge will probably be too tall, so significant material will need to be removed from the feet, but not too much. If using a new bridge with adjusters pre-installed, shaping the feet is harder because they will move; it's really better to have the adjusters installed after the bridge is properly fitted and tested.

Probably should have the strings slacked and out of the way for this work at first, do the shaping to the feet and the bridge top, then test with strings. String notches need to be placed in appropriate places, for that the top of the old bridge can be used if those notches were acceptable.

Of course, all this work also means that the sound post may move or fall. If you're really going to take this job on, you'll need to be prepared to re-set the sound post yourself.

While I've done setup work on a lot of instruments, on a DB, fingerboard dressing and fitting a new bridge are two setup tasks I'd take to a professional, because everything else in DB setup depends on them being right. These, plus years of experience, are all the reasons that a DB luthier can do this work so well.

Best of luck with this!

 

[coyote1]

The other bridge will not be in the correct bridge position. It will be immediately next to that position, with just enough tension to (hopefully) prevent the soundpost from being dislodged. We shall see how it works out… the failsafe, of course, is if I cannot get it where it needs to be I take it to a pro.

I am also considering a fingerboard dressing. But that's an expensive proposition. I could live with an overly growl-y low F (that's the only note in need of adjustment, but it would require a complete fingerboard dressing to correct).

 

[tb-player]

+1 for taking it to a luthier. I took my ply bass to a local luthier and got a new bridge. While there, he did a minor plane on the E-string side of the neck to clean up a slight buzz. It plays so good now and the bridge is fitted perfectly with nice, low action. No offense intended if you're wanting to do it yourself, but it's worth whatever it costs to have it done right.

 

[coyote1]

I don't get it. How do you learn these things if you are unwilling to try? Why the resistance to giving it a shot? Worst that can happen is I don't get it right, and I end up taking it to a luthier after all…

 

[Don Hergert]

Well, actually the way that bridge is warped**, the worst thing that can happen is not doing anything and having the bridge snap. That happens.

I applaud trying to do it yourself, but not by trying shortcuts. Methods for doing bridge replacement are pretty clear for good reason, and they are well documented. As described earlier, I'd recommend following those methods, and being prepared to reset your sound post.

As someone who has done instrument repair and setup and even some mild build projects, my biggest fear is trying to do something for someone and finding it is way over my head right in the middle of the job, so then that person has to take an unfinished instrument to a serious professional to get things fixed. My comments in this thread are probably founded in that fear, which fortunately has never happened so far.

The only real caveat to doing it yourself successfully is that if you get the new bridge in place and working fine and decide you want adjusters, a luthier is the best tooled person to squarely do that work (table saw, drill press, table sander, taps, etc.). So you'd go to the luthier for that, why not just get the whole bridge done by the same luthier?

**EDIT/Correction, re-read your later post, bridge is probably backward, not warped.... As such, is it possible to just turn it around and re-seat the feet?

 

[tb-player]

I don't get it. How do you learn these things if you are unwilling to try? Why the resistance to giving it a shot? Worst that can happen is I don't get it right, and I end up taking it to a luthier after all…

No harm in trying. I did that once. I attempted to shave down a bridge. I measured meticulously and carefully shaped that bridge (it was a spare so I did it just for fun). When I reinstalled it, it was not even close. I learned a bridge isn't designed to be shaped that way. It works in conjunction with the neck and the shape of the top. A lot of factors go into properly installing a bridge.

Keep in mind, you're asking on TalkBass and there are a lot of folks here with a lot of experience. You do what you want, but don't take it personally when the vast majority advises you to go to a luthier. It's the correct thing to do. But hey, give it a shot & let us know how it goes.

 

[fdeck]

I suggest not worrying too much about the sound post. A bungee around the bass, maybe with a book on top where it goes over the sound post, should be enough to keep the post from falling. Also, it's not a half bad idea to mark the position of the post while you can, e.g., with a pencil on a long stick.

I've fitted one bass bridge and one cello. The bass was my Kay, and it came without a bridge or soundpost, plus I had it apart for major repairs. So I had no original bridge or post to copy. I think it's do-able depending on how handy you are, but it's also not an expensive luthier job.

 

[coyote1]

**EDIT/Correction, re-read your later post, bridge is probably backward, not warped.... As such, is it possible to just turn it around and re-seat the feet?

Nope. Measured the possibility …. The compensation for the fingerboard shape prevents that. The E and A strings would be too low.

 

[coyote1]

No harm in trying.

Keep in mind, you're asking on TalkBass and there are a lot of folks here with a lot of experience. You do what you want, but don't take it personally when the vast majority advises you to go to a luthier. It's the correct thing to do. But hey, give it a shot & let us know how it goes.

I'm not taking it as anything against me… I just wonder. If it were a carved bass perhaps I'd think differently. But it's plywood. My method is certain to at least not damage the instrument.

But I've always done stuff like this. Did machine-level programming on a Commodore 64 back in the day. I've built my own bifold exterior doors, framed and installed windows, done drywall and taping/spackling and painting and plumbing and electrical work in my home (I was an electrical apprentice decades ago), done guitar and bass set up, installed a new rear end on an early 1970s Dodge Dart, rebuilt two tonewheel Hammond organs, dozens of other 'skill' things…. I've never messed up. And I'm just an average guy; if I can do these things, anyone can. So I have a bit of difficulty grasping why folks are so afraid to attempt this sort of thing.

 

[Tim Skaggs]

I don't get it. How do you learn these things if you are unwilling to try? Why the resistance to giving it a shot? Worst that can happen is I don't get it right, and I end up taking it to a luthier after all…

No resistance here. I say go for it. I started playing upright around 2002 and have owned three different uprights since then. I put one or more bridges on each bass, and put adjuster wheels in a few of them. Yes, I have messed up a couple bridges, but that was early on. The last several I fitted turned out great. I've even done a couple for other players after they saw how mine looked, and sounded.

I put rosewood adjuster wheels in my last bridge (3/8" shaft in the adjuster wheel) and the first couple bridges I tried to install them in split when I tried to thread the hole in the bridge leg. I discovered the wooden adjuster wheels with the larger shaft go in opposite the 1/4"x 20 aluminum adjuster wheels with the threads of the wooden wheels pointing down into the foot, not pointing up into the bridge leg like the aluminum wheels are usually installed.

As for the sound post moving or falling while working on the bass, see if you can find / borrow a bag of lead birdshot for shotgun shells. It will provide enough weight to keep the top down on the post. You can put it off to the side or toward the neck enough to work on the bass with the strings off. If you work with the bass laying on its back, the post usually stays in place unless it is an unusually loose fitting post, which is a desired thing to some players, and is definitely better that a post that's fitted too tight.

Before you start, get a good telescoping handle mirror (auto parts stores or Amazon), and rig up a pencil on a thin stick of some kind (dowel rod works well). Using the mirror and the extended pencil, mark the current location of the sound post where it contacts the back and the top. You don't have to draw a full circle around the post, just a short line in three or four equally spaced places around the post will give you a reference to see if the post moved and where to put it back. For marking around the post on the underside of the top, you will probably have to get creative on how to put the pencil down through an F hole, but have it pointing up toward the underside of the top. Stiff wire, u-bolt, etc. will work. You'll figure that out.

You definitely want to use the existing bridge to get a rough height for the new bridge. On new bridges, the feet are very thick and the top edge where the strings sit is long. Both can be cut off rough before starting the feet fitting process. Cut it long and work it down to fit.

By the way, if you have a $20k German / European bass from the 1800s, you might want to take it to a highly experienced upright luthier. I was working on two laminated basses and one carved top, none of which were worth even $2k (at the time), so a scratch or ding didn't cause major cortisol flow. My current bass (1952 Kay M-1) wasn't anywhere near mint when I bought it, so any scratches I put on it have blended in….

Go slow, check fit often. When you think you have the feet fitted to the top, you can use chalk line powder on the top of the bass to set the bridge feet on to see if you have a good fit. You want to see uniform chalk on the feet bottoms all the way out to each corner of the foot and all points in between. You can also use powdered graphite to check fit. I have used a Dremel tool for the very fine adjusting of the feet bottoms. Real luthiers use a super sharp knife. I'm not that good (yet).

There are many places on the interwebs with methods, tips, & tricks. Read a lot before diving in.

 

[Tim Skaggs]

Nope. Measured the possibility …. The compensation for the fingerboard shape prevents that. The E and A strings would be too low.

Well, there is a trick, but It's not something to do on a nice bass, however…. if you have a beat up old laminated beast, you can use relatively thin veneer pieces and glue them to the bottom of the bridge feet, but you have to reshape the top of the bridge to the right radius to fit the fingerboard. The reason the veneer has to be thin is that it needs to flex to fit against the curved surface of the feet bottoms. That way, the side of the veneer that sits on the top should be the same shape as the feet, so should fit the top pretty close or will take very minor refitting. If you need like 3/16" or more height, this probably won't work.

 

[coyote1]

Well, there is a trick, but It's not something to do on a nice bass, however…. if you have a beat up old laminated beast, you can use relatively thin veneer pieces and glue them to the bottom of the bridge feet, but you have to reshape the top of the bridge to the right radius to fit the fingerboard. The reason the veneer has to be thin is that it needs to flex to fit against the curved surface of the feet bottoms. That way, the side of the veneer that sits on the top should be the same shape as the feet, so should fit the top pretty close or will take very minor refitting. If you need like 3/16" or more height, this probably won't work.

Thanks… but A) I'd have to re-cut the top of the bridge to match the fingerboard. If I misjudge that, I have to get a new bridge anyway.

B) while the bass is an old laminated beast, it's NOT beat up. Overall it's in great shape, and once I removed the original strings (yes, the guy I got it from had owned it since he was in high school in the 1970s and had never changed the strings!) and installed new ones the bass sounded very good.

C) I'm going to get it right with the new bridge. Just last week I successfully shaped a sitar type 'buzz' bridge for the symp strings of a Coral style sitar-guitar. If I can get that shape right, I'm pretty confident I can get the footings of the new bridge where they need to be.

 

[klyph]

But I've always done stuff like this. Did machine-level programming on a Commodore 64 back in the day. I've built my own bifold exterior doors, framed and installed windows, done drywall and taping/spackling and painting and plumbing and electrical work in my home (I was an electrical apprentice decades ago), done guitar and bass set up, installed a new rear end on an early 1970s Dodge Dart, rebuilt two tonewheel Hammond organs, dozens of other 'skill' things…. I've never messed up. And I'm just an average guy; if I can do these things, anyone can. So I have a bit of difficulty grasping why folks are so afraid to attempt this sort of thing.

I think you just need to get over the fact that part of bridge work is the skill of soundpost setting (despite the confidence professed in your last sentence). The quote above demonstrates that you understand systems that are interlocked physically or functionally. When you fixed the organs, you had to address the power supply before the tone wheels. When you fixed the Dart, didn't you have to disassemble parts of the exhaust and transmission first? How is this different? I guess I don't understand what you don't understand! Moving the soundpost location is a basic lutherie maneuver to effect changes in the sound of a bass, even without reworking of the bridge. There's no guarantee that your new bridge will function sonically the same as the one you are replacing, and some soundpost shifting might be necessary to address that. Maybe you should just do that a couple of times to practice before doing the bridge work. With what you've already accomplished, this shouldn't really be that big of a deal.
That said, the times when I just wanted the soundpost to stay put I just put pieces of tape around both ends, also stuck to the interior of the top and bottom, and just detached them after the strings were tight again. I used masking tape to avoid damage or knocking the post out of place upon detaching.
Have fun, whatever you decide to do!

 

[coyote1]

I never said I was unwilling to manipulate the sound post. I just don't want it to fall in the process of this work; I don't want resetting that post and restringing over and over again if I can avoid it. Given the existence of two bridges (they are coming as a package), I think/hope I can get this done as previously stated.

We shall see… and yeah, I'm going to enjoy the process and learning new things!

 

[BPM Strings]

You will not be able to get a good fit on the bridge feet without taking the string tension down. Your idea is smart and makes sense conceptually, but it will not produce a good result. Doing the sandpaper on the top thing can produce an ok amateurish fit if you are very careful. To get a pro level fit you must do it with a knife and either carbon paper or a grease pencil to read the high spots. If you lay the bass on its back wherever you plan to fit the bridge and take the string tension off, and don't move the bass until the new bridge is on, the post should not fall. If it does it is either too short or in the complete wrong place, and you should address that before fitting a new bridge. I applaud your desire to learn how to do it, and I encourage you to learn how to do it right.

 

[Stuart.C]

the bridge that came with my bass (and by all accounts, is the original) was set up backwards.

FWIW my bridge is setup the same, flat side facing finger board.

I asked the luthier from whom i bought it about it, he said some people fit the bridge that way it's nothing to worry about.

The bass setup is great in every respect, so who ever did it, knew what they were doing.

 

[coyote1]

@BPM Strings: Thank you for that. So I should be able to get most of the way there using my method - and if I feel it necessary, at that point move to what you're recommending. That would minimize the amount of time the bass would be without string tension.

@Stuart.C: I hear ya. This bass has been this way forever… but I know the setup could be better. I have in fact had to cut new string notches to make it at all playable, and even at that I know I can make it more playable. So the risk is incredibly small (bordering on nonexistent), and the potential reward is large. Including a learning experience.

Interestingly, I was in a shop earlier today that has an assortment of uprights. None of them sound as good as mine, even two with carved tops. Likely a string issue, but might have to do with mine being played for 55 years. Or perhaps being old growth Central European wood or something. All these basses, by comparison, sound compressed. It's a fascinating experience.