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Calvin Marks
11-06-2009, 08:59 PM
I just acquired a wonderful travel bass which will make life a lot easier for certain types of gigs. The only issue is, the bass came with a terrible bridge and the string heights are all out of whack. I don't have the cash quite yet to get a new bridge made so I will need to do a temporary job to fix the string heights.

My question is: Should the contour of the end of the fingerboard match the curvature of the top of the bridge?

I just filed down the bridge grooves so that the string heights are:

I - 5mm
II- 7mm
III- 9mm
IV- 11mm

This feels wonderful under my left hand but my bow is still hitting multiple strings at once while bowing. Ie. The D string hits the G and A, and the A string hits the D with the bow.

How can I correct this?


Thanks!

Ken Smith
11-06-2009, 09:20 PM
I just acquired a wonderful travel bass which will make life a lot easier for certain types of gigs. The only issue is, the bass came with a terrible bridge and the string heights are all out of whack. I don't have the cash quite yet to get a new bridge made so I will need to do a temporary job to fix the string heights.

My question is: Should the contour of the end of the fingerboard match the curvature of the top of the bridge?

I just filed down the bridge grooves so that the string heights are:

I - 5mm
II- 7mm
III- 9mm
IV- 11mm

This feels wonderful under my left hand but my bow is still hitting multiple strings at once while bowing. Ie. The D string hits the G and A, and the A string hits the D with the bow.

How can I correct this?


Thanks!

I like about 6-7mm or so clearance every other string at the bridge for French bow and slightly more for German. String heights as mentioned only work if the fingerboard has a proper curve. Sound like this board is too flat or just way off in some way. I can't see it from here so it's a guess. What is not a guess is the fact that your bridge needs a proper curve first. Getting the right string heights you like depends mainly on the fingerboard if bowing is involved.

http://www.kensmithbasses.com/doublebasses/hart/hart-restore-images/hart14.jpg

Your heights are 2mm graduated. Mine are 1-1.5mm from G to E. The Fingerboard curve and dressing makes a world of difference. A bridge is easy to correct, shim or even change. A fingerboard way more work and expense.

Perhaps in the future you will look for these things when buying a bass. The bridge may be the least of your problem here.

Calvin Marks
11-06-2009, 09:26 PM
Perhaps in the future you will look for these things when buying a bass. The bridge may be the least of your problem here.

The bass is in flawless condition, I had it checked out by multiple luthiers. The only issue is the bridge as it was used by a jazz bassist who used a very flat arch as he didn't bow.

Thank you kindly for the information.

Ken Smith
11-06-2009, 09:44 PM
The bass is in flawless condition, I had it checked out by multiple luthiers. The only issue is the bridge as it was used by a jazz bassist who used a very flat arch as he didn't bow.

Thank you kindly for the information.

If I had a Dollar (US or CAN.. lol) for every Bass that a 'Luthier' sold, set-up or approved with a fingerboard-to-bridge ratio/set-up that was not up to my expectations, I would be opening another bank account to put the money in. The other account is getting kind fo full at the moment..:p

Calvin Marks
11-06-2009, 09:59 PM
If I had a Dollar (US or CAN.. lol) for every Bass that a 'Luthier' sold, set-up or approved with a fingerboard-to-bridge ratio/set-up that was not up to my expectations, I would be opening another bank account to put the money in. The other account is getting kind fo full at the moment..:p

I hear you but I know nothing about these types of things. The best I can do is bring the instrument to a reputable person and ask for their experience. I always play an instrument at the shop after work as been done so if there needs to be some tweeking it can be done right then.

Ken Smith
11-06-2009, 10:31 PM
I hear you but I know nothing about these types of things. The best I can do is bring the instrument to a reputable person and ask for their experience. I always play an instrument at the shop after work as been done so if there needs to be some tweeking it can be done right then.

Calvin, you NEED to know these things. The Luthier is NOT going to be playing YOUR bass on YOUR Gig, YOU ARE! You MUST be responsible for what you need in a bass set-up. Know this before you walk out the door with any bass.

Set-up is so personal that a Luthier no mater how good and no matter how much information I give him about what I like and want it still needs to be tweaked in the end. Luckily enough I can do some of this myself and explain the rest of it on the spot to get it corrected.

I was not born with this. I learned it along the way. Do not turn a deaf ear on your needs and abilities to communicate them because the other guy is 'the Luthier'. Learn all you can about what you want and need and know what it looks like, feels like and measures like.

Behind my back and in private you are welcome to discuss all of what I just said with Arnold and Jeff. They know me pretty well in this way.

Calvin Marks
11-06-2009, 11:08 PM
Calvin, you NEED to know these things. The Luthier is NOT going to be playing YOUR bass on YOUR Gig, YOU ARE! You MUST be responsible for what you need in a bass set-up. Know this before you walk out the door with any bass.

Set-up is so personal that a Luthier no mater how good and no matter how much information I give him about what I like and want it still needs to be tweaked in the end. Luckily enough I can do some of this myself and explain the rest of it on the spot to get it corrected.

I was not born with this. I learned it along the way. Do not turn a deaf ear on your needs and abilities to communicate them because the other guy is 'the Luthier'. Learn all you can about what you want and need and know what it looks like, feels like and measures like.

Behind my back and in private you are welcome to discuss all of what I just said with Arnold and Jeff. They know me pretty well in this way.

Thanks for the solid advice.

Pino Cazzaniga
11-07-2009, 07:24 PM
Calvin,
Waiting for a fingerboard dressing, if there is no buzz, you may try 5, 7, 8,5, 10. If still there is no buzz but you hit two strings, 5, 7, 8, 9. If there is room, more string spacing at the bridge may help. This will change the tone and balance, as there will be less pressure on the E side of the bridge. And, if you use a german bow, a lower E string can be uncomfortable. If, if, if....

Matthew Tucker
11-08-2009, 06:19 AM
My question is: Should the contour of the end of the fingerboard match the curvature of the top of the bridge?


No, the shape of the top of the bridge is determined significantly by the curvature of the fingerboard.

To give your bow clearance so that you can easily bow one string at a time the bridge needs to be quite highly arched.

But if your fingerboard is too flat, then shaping the top of the bridge nice and high in the middle to help your bowing won't help, because your A and D strings will be way off the fingerboard and hard to play.

So yes. What Pino (and Ken) said. Start with a FB shaping.

Arnold Schnitzer
11-08-2009, 09:01 AM
Thanks for the solid advice.Ken's advice was anything BUT solid! To do the tweaks he mentions, you will need several tools. Here is a list, along with the dangers of each:

Files: These can give you an abrasion. The point can inflict a small puncture. Gig missed.

Chisels: These are really sharp. They can take your finger tip off, or slice a callous. Gig Missed.

Rulers: These are made of heavy metal. Touching them can mess up your body's delicate balance, as heavy metals are absorbed right through the skin. Also, you can strain your eyes trying to read the itsy-bitsy numbers. Gig Missed.

Knives: These are the most dangerous of all. They can cut, puncture, even kill you. Gig Missed.

And another thing: Wood dust is a known carcinogen. Just a few whiffs and you could need chemo. Gig Missed, career trashed.

So, forget what Ken said. If he wants to risk his career and life messing around with this stuff, let him. But you should let your luthier take all the risks. Oh, excuse me now, the ambulance is here for me. :(

Ken Smith
11-08-2009, 10:11 AM
Ken's advice was anything BUT solid! To do the tweaks he mentions, you will need several tools. Here is a list, along with the dangers of each:

Files: These can give you an abrasion. The point can inflict a small puncture. Gig missed.

Chisels: These are really sharp. They can take your finger tip off, or slice a callous. Gig Missed.

Rulers: These are made of heavy metal. Touching them can mess up your body's delicate balance, as heavy metals are absorbed right through the skin. Also, you can strain your eyes trying to read the itsy-bitsy numbers. Gig Missed.

Knives: These are the most dangerous of all. They can cut, puncture, even kill you. Gig Missed.

And another thing: Wood dust is a known carcinogen. Just a few whiffs and you could need chemo. Gig Missed, career trashed.

So, forget what Ken said. If he wants to risk his career and life messing around with this stuff, let him. But you should let your luthier take all the risks. Oh, excuse me now, the ambulance is here for me. :(

Arnold, what did I say?:confused:

I was only referring to the final Bridge and maybe some Nut tweaking? Mad at me? Sounds like your Nuts need a little tweak themselves there..

BTW, on the Electric Basses we make (http://www.kensmithbasses.com/) I tweak Bridges and Nuts (and make them) every day. Wood is so much easier and more fun to work with than Brass.:)

To be more clear about what I was trying to tell Calvin, a person should know himself what he wants and needs in a set-up so that he can TELL his Luthier what to fix or change based on playing the bass and giving his feedback about what doesn't feel right.;)

Not actually do it himself. Well, you know, personal Nut tweaking aside.. :eek:

I wonder if the Ambulance brought your favorite Jacket? You know that white one that takes another person to tie it in the back for you..:p

It's for reasons like this mainly that over the years I had to learn to do my own Tweaking..:cool:

Calvin, next question please..

Calvin Marks
11-08-2009, 06:38 PM
Wow! I feel pampered! Four luthiers (well, three and a guy that likes to file nuts) :p all answering my questions. I sincerely appreciate all the advice.

Reading this, I decided to take in my other bass as well. The "Gormani" bows great but hey, it could definitely be better and easier.

First thing off, my luthier told me that my "Gormani" had relatively no scoop to the fingerboard, and that shaping the top of the bridge would help bowing, but like Matthew suggested, it would be difficult to press down on the D and A strings as they would of course be quite high off of the fingerboard.

So, now I have two basses in for adjustments. Hopefully now I'll know more before I purchase another instrument.

1) Fingerboards to be plained.

2) Top of bridges to be re-cut.

3) Overall mass of bridge to be reduced on the Gormani


For orchestral "slamming", do you all recommend 1mm height increments or 1.5mm?

I've always been curious what the ballpark figures are to make a string resonate properly. Surely the lowest strings needs minimum 9mm to vibrate properly?

Thanks again!

Ken Smith
11-08-2009, 10:35 PM
What is 9mm? The E? I prefer to 'pull' the sound rather than to 'press' for it. I do dig in but more pulling than pressing. Also, I bow closer to the bridge when more sound is needed and I don't hit the FB that way. A really good bow helps this as well.

Scoop/Camber in the FB on my basses are very slight. Less than 1mm the first octave and less than 2mm overall. Ask Arnold as he did them for me. This would be the Hart and the Martini which are the Basses I play the most now that the Gilkes is gone. The Gilkes had a bit more camber mainly because of the neck movement when strung up. You can plane it flat but under tension, all bets are off. Most of my Necks have had Graphite Bars put in for stability. Helps to control the stiffness and desired camber over a normal neck without the Graphite CF.

I think for graduation 1mm for tight strings and 1.5 for looser ones. Also, this depends on how tight the bass itself is. Not all basses have the same taughtness in the string from what I have seen.

For digging in and playing hard ask Arnold how he set-up the basses for some of the Guys in the Met that hammer the instrument.

On my Hart with Belcanto's Orch/Ext. set I have G-E, 4, 5, 6, 7mm with the string spacing about 27.5mm centered. The height as i mentioned before of the middle string is about 6mm so a nice playable curve. Plays like a dream.

The Martini with Evah Weich/Ext. set I have slightly higher strings at the end of the FB and graduating about 1 1/4-1.5mm per string so a tad more curve but the same bridge for some reason. The spacing is 28mm centered on the Martini. Hard to measure these things exactly.

My basses play with ease for the most part. It's the music that's hard to play, not the bass.

Depending on the music, the season, how I feel and whatever, I might raise the strings on occasion if need be. These settings are about as low as I go. With tighter strings, you can go lower than with looser ones. Still, I like not to think about the bass when playing it, only the music which is usually hard enough.

Matthew Tucker
11-09-2009, 06:59 AM
Calvin it depends how, and how hard you play. Ken's 4mm-7mm setup is pretty low. Start digging in with the bow and somethings going to rattle at some point unless you're really careful. But play smoothly and you're fine. However, find yourself playing jazz pizz with a piano, unamplified, and you're going to need higher strings to pull some volume.

If you have adjusters you can play around, but if you don't, start higher say even 8,9,10,11mm and bring the height down slowly. I find a good all-round setup is 6,7,8,9 or 7,8,9,10, at least, start like that because it's easy to measure, then tweak away. Take the bass away with the string height a little higher than you think you like it, play with it a while, then if you want, take it back in and get the luthier drop it down a bit further. He/she probably won't charge you to do just that wee tweak.

Calvin Marks
11-09-2009, 08:19 AM
I assume that in order to achieve the proper curvature at the end of the board, the entire length of the fingerboard would need to be plained, correct?

Ken Smith
11-09-2009, 08:49 AM
I assume that in order to achieve the proper curvature at the end of the board, the entire length of the fingerboard would need to be plained, correct?

The Fingerboard needs the arch it needs. This will depend on the shape and thickness of the FB at the start. Often though, the FB may need to be replaced if there is not enough wood to work with to get it right. Why do all that work only to end up with a thin fingerboard? A thin fingerboard gives the neck less support and in time will bend requiring more FB planing. That is usually the sign of the need to replace the FB.

Once again, take the bass to a 'qualified' Luthier and go from there. Eventually you may learn yourself what a bass needs before hand regardless of the need for the Luthier to do the actual work for you. 'Knowing' is often half the battle.

Calvin Marks
11-09-2009, 08:59 AM
The Fingerboard needs the arch it needs. This will depend on the shape and thickness of the FB at the start. Often though, the FB may need to be replaced if there is not enough wood to work with to get it right. Why do all that work only to end up with a thin fingerboard? A thin fingerboard gives the neck less support and in time will bend requiring more FB planing. That is usually the sign of the need to replace the FB.

Once again, take the bass to a 'qualified' Luthier and go from there. Eventually you may learn yourself what a bass needs before hand regardless of the need for the Luthier to do the actual work for you. 'Knowing' is often half the battle.

Indeed. Thanks again.

Matthew Tucker
11-09-2009, 08:10 PM
Calvin, just so you know, the curvature of the fingerboard is not necessarily the same from end to end. Quite often it is flattish near the nut and then much more pronounced curve closer to the bridge, and the important thing is that between the two extremities the transition is completely smooth.

Think of a "contact path" directly under each string; that's how a good luthier will approach the fingerboard shaping, by getting the path right for each string, including the right amount of scoop from nut to FB end, then smoothing over the flats so that the fingerboard is even across the board from end to end. Then checking again there are no high spots, then a final polish.

It can be quite a few hours work.

Calvin Marks
11-11-2009, 11:21 PM
I get both basses back on Friday. I'll let you know the results.

Calvin Marks
11-14-2009, 04:42 PM
Got the bass back yesterday. Sounds fantastic. The bridge spacing has been widened from 25 to 26.5 centre to centre of each string. The bass is shacking the walls it's so freaking loud.

Tomas Bouda
11-14-2009, 11:06 PM
nice. maybe i'll hear it around toronto sometime!