Newbie - bridge feet contour question

[what the pluck]

Hi There,
This is my first post here. I have recently purchased a cheap ply bass as a re-introduction into upright (i played over 20 years ago and have played bass guitar since) until I have the means to get my hands on something better. I am keen to do some basic set up my self for now so I can get to know the bass. I played with the bridge that came with bass knowing that it would be changed along with a fresh set of strings and followed much of the great advice on this forum and managed to get the bass sounding and playing ok. Until I experimented too far and took too much off the top of the bridge on the G side and got a bit of a buzz.

I am going to fit an adjustable bridge and am about 75% confident I can get it to suit my purpose for now. (I am not touching the sound post! It seems in place, maybe when I am a bit more adventurous I will tinker with it)

Okay.. My question is this. Does the tension of the strings on the bridge cause the legs of the bridge to open up a little bit thus causing the contour not to line up? Is there something extra to shaping the feet with sandpaper on the spot where it will sit. Any tips to get this right would be great.

Thanks....

[William Hoffman]

Originally Posted by what the pluck

Okay.. My question is this. Does the tension of the strings on the bridge cause the legs of the bridge to open up a little bit thus causing the contour not to line up? Is there something extra to shaping the feet with sandpaper on the spot where it will sit. Any tips to get this right would be great.

Thanks....

i think the short answer is you want the bridge feet to fit the contour of the top exactly when sitting on the correct spot. you shouldn't be able to even force a piece of paper under the feet from any direction. the legs of a standard size bridge give way slightly under full string tension, and this is said to be a factor in using the sandpaper method you mention. i have bridge height adjusters that remove that issue completely, and the feet are always 100% flush with the top.

maybe Matthew or one of our luthiers will chime in here...

there are different tools and methods you can use to shape the feet. the sandpaper method is not, in the opinion of many, the best way to go because less precise. still, some do it that way. i am not a luthier, but i have fit several bridges exactly using the lipstick method Arnold talks about in the thread below. took me many hours but i am very pleased with the result.

there is of course a lot of good advice here on TB on fitting a bridge. you can access it easily by running a search. starting a new thread before you've done that may actually be less helpful. here is one thread that may interest you. good luck and be careful. remember: it's easy to take wood off, but you can't put it back!

fitting the bridge feet?

[gbaker]

Originally Posted by what the pluck

Hi There,


I am going to fit an adjustable bridge and am about 75% confident I can get it to suit my purpose for now. (I am not touching the sound post! It seems in place, maybe when I am a bit more adventurous I will tinker with it)

Okay.. My question is this. Does the tension of the strings on the bridge cause the legs of the bridge to open up a little bit thus causing the contour not to line up? Is there something extra to shaping the feet with sandpaper on the spot where it will sit. Any tips to get this right would be great.

Thanks....

First - don't worry about the bridge spread under pressure.

If you are going to install adjusters in your bridge:
I have fit about 6 bridges with adjusters, these are my opinions:

You will need a drill press and a drill vise, a tap to match the adjuster threads and a drill to match the tap and also a drill to match the diameter of the stub end of the adjuster. You will also need a table saw with a small part clamp or sled or small precision miter saw of some kind. If you don't have access to the above, consider just grafting a wooden foot pad on the short leg for now.

There are detailed directions here in TB - do a search. Drill with the tap screw before cutting the bridge to assure alignment after.
Be very careful about drilling parallel to the flat side of the bridge and not too deep toward the top of the bridge but allow for the taper at the end of the tap. Provide relief for the rounds on the thumb wheels. Put soap on the threads for some lube.

Expect to have to re-fit the bridge feet to the top after the adjusters are installed. I have tried knife-trimming the feet gut I find that #100 adhesive-backed sandpaper on the top works fine if you are careful not to rock the bridge while you are sanding. I use a pop-sickle-like stick to keep the feet in line while sanding. I make a final check with lipstick.

- BUT -
If you are going to install a new bridge that comes with adjusters already installed then you need to do a good deal of work on the bridge itself as it will probably need to be thinned and height- sized (your old bridge will prove handy) as well as fit to the top. Search on "Fitting a Bridge".

BTW during all this your sound post may fall. Don't panic, it is not THAT hard to replace, even using a BBQ fork, a framing square and an inspection mirror. For a bit of insurance before you start the bridge-work place a mark on the bottom of the SP and the bottom plate so if it falls you will have a landmark to reinstall it.

Hope this helps.

[what the pluck]

Thanks for the replies and links. I am feeling pretty confident to be able to give it a go. I am living with the old bridge for a while and gradualy making minor adjustments to it the more i play. Little bit if experimenation but I think I should achieve a good template for when I place the new one (which will have the adjusters already fitted). I am going to keep playing it as it is for a while and tweak until the bass feels as good as I can get it. I will update once I have.
Thanks.

[what the pluck]

Finally got the bridge on, the fit of the feet seems pretty good. I played the bass for a few days and found the E string sounded pretty crud, the A had a little buzz around C, the D sounded the loudest and clearest and the G had a buzz around C too. I raised the height until the E sounded ok and reshaped the top of the bridge to get the other strings back down to just above buzz height. I will play it for a while and see how it goes. Luckily the soundpost didn't fall. It actually looks quite firmly wedged in there. Not sure if this is a good or bad thing!

Something I am not too sure about, when adjusting the bridge height with the adjusters, should both be adjusted the same amount? If they are done in different increments will the affect the feet seating?

This was a bit of a learning experience for me and I am somewhat pleased with the results, no doubt when I eventually do get it to the Luthier he may have other ideas. But for now I am keen to use this cheapie as a means to explore the player/ instrument relationship before I get something nicer.

My next experiment is with an old contact mic I have, but for that I will look elsewhere on this forum...

[Matthew Tucker]

Originally Posted by what the pluck

no doubt when I eventually do get it to the Luthier he may have other ideas.

[Andrew McGregor]

When using adjusters, always move them the same amount (near as you can). You can't shift the relation of the E string height to the G string height with the adjusters, instead you fix that by moving the whole bridge sideways. If you think about the geometry of the situation, you'll see why that is so.

[what the pluck]

I still was not happy with the E string.

With the bridge foot middle directly over the bass bar the bridge is about about 3mm off centre. The safe position for the sound post (which I marked before changing the original bridge) is sitting directly in line with the centre of the foot on the G side. Is 3 mm off centre a big deal?

Even when I raised it considerably to the point where it was uncomfortable to play I was still getting a dead sound on F# up to A. I put some chalk under the string and found where it was buzzing, which was around B. For the hell of it I stuck a bit of card where the string exits the tail piece to see if that would change anything and to my surprise it did! What is this telling me (apart from I have a pretty crappy bass!) I am keen to use this bass to explore set up etc before I move on to something better as a means to get a bit of an understanding on how these things work!

Where the chalk rubbed on the fb, is this where a scoop would be?

Also, it sounds much better arco, even with the Innovation Rbs on it.

Cheers...

[Matthew Tucker]

Well it might be the sound post position, or fit, or any number of things, including a too-thick/heavy top or a dead tailpiece or a badly-shaped bass bar or bridge or fingerboard ... and cheap ply basses rarely have a good E string sound anyway. Or it could be yr technique.

You could try moving the soundpost towards the FF a bit. Normally that will tend to increase volume of the E string. But it depends on a bunch of other things. What's the string length? Got any pictures esp of the bridge area? that might tell us something. Good luck.

[Cody Sisk]

Originally Posted by Matthew Tucker

Well it might be the sound post position, or fit, or any number of things, including a too-thick/heavy top or a dead tailpiece or a badly-shaped bass bar or bridge or fingerboard ... and cheap ply basses rarely have a good E string sound anyway. Or it could be yr technique.

You could try moving the soundpost towards the FF a bit. Normally that will tend to increase volume of the E string. But it depends on a bunch of other things. What's the string length? Got any pictures esp of the bridge area? that might tell us something. Good luck.

Maybe this is why many of us make a career of this? DIY'ers find the presence of so many variables AFTER they dive in head first thinking the project is easy. I might be putting my foot in my mouth, but I find many threads like this insulting to our specialized trade. Normally I keep my mouth shut, but for now, I feel it necessary to speak up.

Shaping the wood to fit isn't the only thing involved in a bridge fit. For a luthier who people come back to time and time again, it's much more than that. It involves first picking an appropriate bridge blank that will accommodate the position of the bass bar in relation to the top.

Then the woodworking happens- fitting the bridge. This is the part that seems so simple to the DIY'ers. It IS a simple concept and the work isn't that difficult. This is not the part of the process requiring the most expertise.

Then involves some soundpost adjusting, some minor tweaks applied that the luthier has learned through experience. They can also compile a list of specifics regarding the setup that they might recommend to the customer after doing the work they were commissioned for such as: redressing the fingerboard, swapping out the tailpiece, trying out a different endpin configuration, changing the nut, etc. Their hearts and passion (as well as their limited pocketbook) lies in making an instrument live up to its full potential.

Mentioned in this thread "fortunately the soundpost didnt' fall". You've got the skill necessary for fitting a new bridge yet don't know how to set a soundpost? If I were your mentor and you were a luthier apprentice, this would not be a concern as you would learn skills in an appropriate succession.

I hate to rock the boat and ruffle feathers. Please don't turn my remarks here into a flame war. That's not my intent here, I just want to voice this as a general frustration I have as a luthier who draws a living doing this kind of work. I'm not alone either. Matthew tried to make a subtle hint and it obviously wasn't taken. Unfortunately for me, I'm quite a bit more overt and brazen..

[Matthew Tucker]

I *think* I know the owner and he wants to try stuff out, and that's fine with me ... and I'm pretty sure I'll end up seeing the bass in question before too long ... but Cody of course you're right, there's a lot to it - which is why it's hard to give a solution in a forum post - and at the end of it all, as my brother always reminds me, "you can't polish a turd" ... but you can sometimes buff it up a little IF YOU KNOW HOW!

[Gearhead43]

Doing your own work on your bass is not rocket science, but you have to do the proper research, read read read, get the books, etc. A hack job is a hack job no matter what kind of work you're doing.

Me? I've been a woodworker and mechanic most of my life. I had the confidence to proceed, but I wanted to do it right. Plus, I couldn't afford to pay a luthier's fees for the work I needed done when I bought my bass years ago. (still can't, I'm a musician ) So I read everything I could find on bass luthiery, including most of the threads posted here as far back as they go. I bought some new tools when I had money.

My humble used plywood bass needed a complete setup. (It never had been set up, was beat up, and bodged up by the previous owner) It needed a new bridge, seams reglued along with a bunch of other little things. I have done all the work myself, including cutting/shaping a new bridge blank. (twice! got it right the second time) Altered and adjusted the soundpost for best tone, trimmed down the nut and filed the grooves, new tailgut, etc. My bass plays and sounds alot better than it should for what it cost me.

I've done two other complete bass setups for friends, fixed a neck break, and a bunch of seam reglues, pickup installs, along with other simple setup work. All this was done for free, for experience, and everyone has been very happy with my work.

Doing your own work is possible - but for ****'s sake do it right! Luthiers all started somewhere.

You know damn good and well if you should be doing the work - some people just don't have the mechanical aptitude - so know when to see a professional.

With my limited luthiery experience, I know when to get the work done - such as with fingerboard planing. I won't attempt that until I get a good teacher someday, maybe an apprenticeship later down the road when I am not so busy playing music.

[what the pluck]

Thanks for your replies.

Dallas, I am not looking at making a career of this or anything, just have an interest and am keen to learn what I can on a bass that I picked up pretty cheap that probably wont see any gigs. Sorry if I insulted you, I am just that type of person who likes to know as much about their interests as possible and am willing to try things from learned information. Its just my nature, im a curios ****

I fully respect a skilled Luthiers knowledge and craft and would no way recommend anyone to tackle such a task and expect a result anywhere near what you guys achieve. I appreciate your comments.

The sound post did fall, a few times, but I marked its position on the back and top of the bass plus on the bar itself so I could match it. I used a couple of bbq skewers bent into shape. Didn't find it a too daunting task.

Yes your right Mathew, its me! You will end up seeing this bass at some stage, if it doesn't implode first

You cant Polish a turd, I use that alot in my profession as well (sound engineeer) BUT.... You can roll it in glitter!

Cheers

[Matthew Tucker]

Originally Posted by what the pluck

BUT.... You can roll it in glitter!

What a prospect!

Or as my OTHER brother just told me "you can't make a racehorse out of a pig, but you can make an awfully fast pig ..."

[Cody Sisk]

Originally Posted by what the pluck

Thanks for your replies.

Dallas, I am not looking at making a career of this or anything, just have an interest and am keen to learn what I can on a bass that I picked up pretty cheap that probably wont see any gigs. Sorry if I insulted you, I am just that type of person who likes to know as much about their interests as possible and am willing to try things from learned information. Its just my nature, im a curios ****

I fully respect a skilled Luthiers knowledge and craft and would no way recommend anyone to tackle such a task and expect a result anywhere near what you guys achieve. I appreciate your comments.

Cheers

I understand and encourage your curiosity, though I caution you about what you're getting into. You will spend years honing your skills, might go through a few bridge blanks before getting it right. I have had to make numerous custom tools that I use for fitting my bridges and installing adjusters. This takes investment of time and money. I just hope your motivation is like Gearhead's. He has both prior mechanical skill and a passion for learning the craft and has obviously devoted quite a bit of time to it.

If a player's motivation is to simply save some cash by doing the work themselves, they are gravely mistaken. Those specifically are the people who don't have what it takes to do this kind of work, will mess up their instrument beyond their own capability of fixing it, and will end up paying the luthier who fixes it more than they would have paid for the work initially..