Interesting change in action

lowendgenerator · #1 02-12-2009, 06:52 AM

Sunday I played my SX bass at band practice, and I left it at our climate-controlled rehearsal space. I remember thinking "I would like to take the action down a hair, it's a little high.", but I was getting good tone from it, so I left it alone. It's been a rock solid bass up until this point.

When I got to practice last night, the action on my bass had dropped to the point where I was fretting out on the 1st fret, and buzzing pretty good all over the rest of the neck. I made no adjustments, where did this change in action come from? Did the truss rod take some steroids when I wasn't looking? In my 10 years of playing bass, I've never had this problem. The bass sat in it's stand, just like it always does. I brought it home with me last night and I plan on giving the truss rod a little tweak to put a bit of relief back in the neck, but I'm still perplexed.

Anyone else suffer from a case of wandering action?

Easy8 · #2 02-12-2009, 11:21 AM

Is it a Jazz neck?

I find I have to tweak the trussrod on my Jazzes every four to six weeks.

I've had a Precision for over 35 years and I've never had to adjust anything on it.

ehque · #3 02-12-2009, 11:38 AM

Well your rehearsal space may be climate controlled, but that's just temperature, isn't it? Humidity levels may be different, which will throw your neck out of whack.

nightcityburn · #4 02-12-2009, 11:39 AM

Quote:

Originally Posted by ehque

Well your rehearsal space may be climate controlled, but that's just temperature, isn't it? Humidity levels may be different, which will throw your neck out of whack.

+1.

This has happened to me from time to time.

lowendgenerator · #5 02-12-2009, 11:44 AM

It's somewhere between a jazz and a precision thickness. I own a lot of Jazz basses, and never need to adjust them. This happened over the course of 3 days, and the action came down dramatically.

The humidity is pretty constant at 30%. We have a hygrometer in the room. We're nerds like that. I'm thinking it may have been dropped/knocked over when I wasn't there and no one wants to fess up. I can't think of anything mechanical that would cause this.

Although, the humidity may have spiked while I wasn't there for 3 days. Wouldn't a sudden rise in humidity cause the next to become more flexible and bow forward? IDK, I'm gonna let it sit here for a few days and monitor it. Maybe it will go back without any changes.

Turnaround · #6 02-12-2009, 01:39 PM

Quote:

Originally Posted by lowendgenerator

Wouldn't a sudden rise in humidity cause the next to become more flexible and bow forward? IDK, I'm gonna let it sit here for a few days and monitor it. Maybe it will go back without any changes.

An increase in humidity will cause the neck to bow back, not forward. As the wood absorbs moisture the wood expands slightly. Since the wood expands but the trussrod doesn't, the effect will be the same as tightnening the trussrod, thus introducing backbow.

lowendgenerator · #7 02-12-2009, 01:49 PM

Quote:

Originally Posted by Turnaround

An increase in humidity will cause the neck to bow back, not forward. As the wood absorbs moisture the wood expands slightly. Since the wood expands but the trussrod doesn't, the effect will be the same as tightnening the trussrod, thus introducing backbow.

O RLY?

This changes everything. Thanks for the knowledge.

xgator4u · #8 02-14-2009, 11:41 AM

Quote:

Originally Posted by Turnaround

An increase in humidity will cause the neck to bow back, not forward. As the wood absorbs moisture the wood expands slightly. Since the wood expands but the trussrod doesn't, the effect will be the same as tightnening the trussrod, thus introducing backbow.

+1
Yup, I live in So. Fla. where humidity is a constant issue, drives me nuts.

Stevem627 · #9 02-14-2009, 12:09 PM

My guess is that you are correct that it might have taken a fall. Have you been able to adjust it back to correct setup?

lowendgenerator · #10 02-14-2009, 05:12 PM

Quote:

Originally Posted by Stevem627

My guess is that you are correct that it might have taken a fall. Have you been able to adjust it back to correct setup?

Hey Steve,

I've been letting it sit in it's bag for a few days, see if it fixes itself. If not, I'll give the truss rod a little tweak. The one time I don't have a wrench in my bag, ya know? *sigh*

xgator4u · #11 02-14-2009, 05:28 PM

this is in its bag, in the environment it is accustomed to correct ?

lowendgenerator · #12 02-14-2009, 09:56 PM

Its in the bag, sitting in my house. Before it was on a stand in my rehearsal space. Haven't looked at it, but I would be surprised if it went back on its own. My guitar player leaves his Les Paul there all the time, albeit in its case.