Lying down or on its side

wyliee · #1 08-13-2004, 06:34 PM

It's not what you think.

I've seen jigs for working on basses at Stewart MacDonald and one of the technicians that used to work on my basses did all action adjustments with the bass in a playing position.

However, nearly every other technician I have ever seen makes adjustments with the bass lying flat.

The justification said technician gave was that gravity has a definite effect on action adjustments and one can be more precise by holding the bass in the natural playing position.

That makes sense to me, but are we talking about thousandths of inches here? Is this taking it to the nth degree or something that makes a real difference?

Thanks,
-Eric.

nonsqtr · #2 08-13-2004, 07:53 PM

Hi Eric, I'd say it depends heavily on the bridge and the saddles. Sometimes the little saddle screws can get very loose, and it's possible that's the kind of thing the tech was talking about. On the other hand, if it's a good tight bridge, there should be no difference. You can look at the saddle screws as "anti-gravity devices" designed to hold the saddle in a fixed position. Movement due to gravity would be a defect in the saddle, and adjusting it in sideways or right side up would only be a band aid that addresses the symptom and not the problem.

Trevorus · #3 08-13-2004, 11:16 PM

There is another issue going on here. When you have a bass hooked up to a proper tuner, i.e. strobe tuner, the weight of the neck does change the pitch noticeably. Laying down is the most accurate way to adjust because it usually will not move as much as it will when it's in the playing position. But jigs that hold the bass in playing position will help greatly. The action changes only VERY slightly

Ozzyman · #4 08-15-2004, 09:31 PM

The tighter your string tension the less problem there will be I think. If you have floppy strings (ie a 5-string) then listen to trevorous.

Trevorus · #5 08-15-2004, 10:16 PM

It doesn't matter what the string tension. It does it either way. What matters is that you keep the neck in a constant position. This just reduces the impact of a variable that really cannot be avoided.

nonsqtr · #6 08-19-2004, 12:44 AM

Somehow I can't imagine that would be a significant factor with a good bass. I mean, if the action (or intonation) changed as the bass changed positions, then all kinds of wild things might happen during the course of a gig. A lot of people get physical with their instruments on stage, don't they? I've never noticed the action changing when "I" do that kind of thing, and I'm anal enough about my setups that I'd probably notice it. I would guesstimate that with a decent neck the deviation might be on the order of "microns", which probably isn't noticeable. And that would be distinct from larger fractions of a millimeter, which probably "would" be noticeable.

Trevorus · #7 08-19-2004, 01:32 AM

I'm not really talking about the action changine at all. The pitch changes. Which would make intonating the instrument almost completely impossible. The action does not change enough for anyone to notice without high-precision measurement. The pitch does. WHich is the basis for a setup. Sorry if I keep going on.

Try it for yourself. If you have access to a strobe tuner, or download a program called G-Tune. Really good strobe tuner program. Very precise, especially when using a high quality audio interface.

RAM · #8 08-19-2004, 07:47 AM

Quote:

Originally Posted by wyliee

That makes sense to me, but are we talking about thousandths of inches here? Is this taking it to the nth degree or something that makes a real difference?

Thanks,
-Eric.

Not long ago I visited the Lakland factory for them to plane and level the fretboard on my Spector. The setup guy, Carl, pulled a single human hair from his head, measured the hair for me, showing me it was mere microns. Then he showed me how much something that *tiny* can throw off an entire fretboard.

The point is, thousandths of an inch mean more than you think.

That said, there are different theories in luthiery, like any other art. Some believe final setups should be done with the bass in playing position. Personally, I believe this theory. YMMV.

lonote · #9 08-19-2004, 08:09 AM

If Dan Erlewine says it matters, it matters.

ebozzz · #10 08-20-2004, 08:36 AM

Quote:

Originally Posted by RAM

That said, there are different theories in luthiery, like any other art. Some believe final setups should be done with the bass in playing position. Personally, I believe this theory. YMMV.

That is correct. Laying the bass down adds relief to the neck. Making adjustments while the instrument is in playing position gives you the most accuracy.

kirbywrx · #11 08-21-2004, 03:05 AM

Quote:

Originally Posted by wyliee

Is this taking it to the nth degree or something that makes a real difference?

No. IMO it makes no difference. This may sound harsh, but its probably just a gimick, something to make the customers believe that their attention to detail is immaculate. Dont get me wrong, im sure it is, but i cant see how gravity is going to create a notiable affect on the strings and the action etc.

Its like everything in the universe has its own gravitational field, ie, everything is pulling everything towards it. Pluto is pulling me closer and closer to it, but its not going to make me fall over. Plutos gravitational affect on me is sooooo minute that even if calculated, it cannot be put to any good use, its so small that it can be neglected. Gravity and its affect on the action of guitar strings (IMO) is exactly the same.

ebozzz · #12 08-23-2004, 07:16 AM

Quote:

Originally Posted by kirbywrx

Its like everything in the universe has its own gravitational field, ie, everything is pulling everything towards it. Pluto is pulling me closer and closer to it, but its not going to make me fall over. Plutos gravitational affect on me is sooooo minute that even if calculated, it cannot be put to any good use, its so small that it can be neglected. Gravity and its affect on the action of guitar strings (IMO) is exactly the same.

Pluto doesn't have strings on it though.

RAM · #13 08-23-2004, 07:25 AM

Quote:

Originally Posted by kirbywrx

Pluto is pulling me closer and closer to it, but its not going to make me fall over. Plutos gravitational affect on me is sooooo minute that even if calculated, it cannot be put to any good use, its so small that it can be neglected. Gravity and its affect on the action of guitar strings (IMO) is exactly the same.

Are you saying Pluto's gravitational field is almost as strong as Earth's? Or that you're even close enough to Pluto to be potentially affected by its gravitational field?

kirbywrx · #14 08-23-2004, 05:52 PM

Quote:

Originally Posted by RAM

Or that you're even close enough to Pluto to be potentially affected by its gravitational field?

Yeah, everything in this universe is attracted to everything else with a gravitational field. Its just that in 99.99% of cases, these forces are so minute that they are deemed useless.

Im not a astronomer by any means, this is just what my physics teacher told me

ebozzz · #15 08-24-2004, 08:43 AM

Quote:

Originally Posted by SMASH

Why not just do what most people do - adjust it in a comfy position laying on a table or in your lap, then pick it up in playing position to check the action/tuning/intonation. If it needs more adjusting, put it back down. It ain't that hard.

I'm with ya!

I just don't think that it's accurate to adjust and check the results while the instrument is lying down.

nivagues · #16 08-25-2004, 08:14 AM

IMO...it should be done in the play position (seated with Bass on lap) to take gravity out of the equation.

Axe on bench, for example, with E string set to say 3/32". In the play position it will be around 4/32".

Just a thought

r379 · #17 09-01-2004, 02:31 AM

Lacking a good place to lay my bass down to work on it, Ive just been doing saddle adjustments/intonation while wearing it. Maybe I've been doing it the right way accidentally.