Any 1 piece pine bodies warping?

[guitarbuilder]

May I please get some input from those of you with one pc. pine bodies? Have you noticed any significant changes in the flatness of your pinecaster bodies if it came from say.... up north and went to a dryer climate? I was wondering if an owner from the Southwest US can expect to see significant warpage with a flatsawn body.Thanks.
Marty

 

[Al Watsky]

They can cup.
Slab sawed pine is prone to cupping.
It would need actual seasoning not to.
Beyond kiln drying.
The degree of the cupping depends on its proximity to the center of the log.

 

[Ronkirn]

A correctly sealed and painted body made of 1 piece Pine or any other wood, will not, cannot, absorb enough moisture to warp under normal circumstances.

Now if you want to "press the envelope" yeah... sure.... but consider, it takes about 1 year per inch of the wood's thickness to correctly dry, so roughly 2 years for a typical body. You can assume the reverse is correct, that under normal atmospheric conditions it will take about 1 year per 1 inch to absorb moisture IF the entire surface of the body is exposed consistently to increased humidity. Seal the rascal, and there is no way enough moisture can creep into the screw holes, or other areas where the raw lumber may be exposed.

If the body is exposed to heat, or cold on one side, that can make the wood fibers on the exposed side expand (heat) or contract (cold) and cause some miniscule cupping, but that would take a lot of exposure.

But generally as long as you are not absurdly careless in the care of your guitar, you’re gonna be fine.

The last thing, internal stresses resulting from growth can cause the wood to warp, but in a typical body, the wood has been cut to thickness and laying around long enough for any of that sort of foible to surface. If you harvest your own lumber, I would put it in the attic, and as long as you remember it’s up there, it’s not ready. Once you forget it (several years) then it might be about ripe.

Ron Kirn

 

[Jack Wells]

Well................. I'm in the high desert Southwest. If someone wants to send me a one piece pine body I'd be more than happy to give it the dry climate test. Probably be best to continue the testing for several years.

 

[originalmatthew]

I live in colorado springs...very dry climate....any lumber I order for bodies, i let sit for at least 3 months. I have seen wood from damper climates do some weird stuff in that short a time span. Same with necks. They "shrink" really fast in this climate. I have gotten necks where the frets felt great when they arrived, and a month later I have to dress the fret ends. If you are getting a raw pre-cut body from anywhere but the desert southwest, i would let it sit for a while to see what's going to happen. If it's sealed and finished, it should be ok, like Ron said.

 

[Nick JD]

No finish will stop a wood from reaching its Equilibrium Moisture Content. Even polyurethane finished wood will eventually reach a 6% EMC in a 30% relative humidity environment. 75% humidity = 14% EMC.

In maple, a 6% change in EMC will result in a 2% tangential change in size.

Equilibrium moisture pressures are surprisingly powerful. Enough to crack (microscopically) a finish to give a path to water vapour.

If the design of a wooden guitar doesn't allow for expansion and contraction, this tangential (also radial and longitudanal to a lesser, but significant extent) shifting can result in warping.

It'll definately sprout your frets (any finish) and wreck your tuning.

(link removed)

 

[Shepherd]

Stop, your making my head hurt.

 

[Nick JD]

Stop, your making my head hurt.

Just trying to keep it real . There's so much folklaw and conjecture in guitar-land that if it was the medical profession we'd still be bloodletting to cure what ails.

 

[stevieboy]

No finish will stop a wood from reaching its Equilibrium Moisture Content. Even polyurethane finished wood will eventually reach a 6% EMC in a 30% relative humidity environment. 75% humidity = 14% EMC.

In maple, a 6% change in EMC will result in a 2% tangential change in size.

Equilibrium moisture pressures are surprisingly powerful. Enough to crack (microscopically) a finish to give a path to water vapour.

If the design of a wooden guitar doesn't allow for expansion and contraction, this tangential (also radial and longitudanal to a lesser, but significant extent) shifting can result in warping.

It'll definately sprout your frets (any finish) and wreck your tuning.

(link removed)

So, is that a yes, or a no?

 

[Nick JD]

So, is that a yes, or a no?

The $64K question.

It's all about the interplay between longitudinal, radial and tangential expansion and contraction. It's called differential shrinkage - and can't be cured with viagra.

This article explains it well. It will have you looking a lot more closely at the grain patterns in the wood you are about to buy. There's more to pretty grain than prettiness...

Will a pine body warp? Maybe, maybe not. Each piece is unique. After reading the DeWalt article, you'll realize that sweeping generalizations with wood are next to useless - and buying wood from someone who knows about wood is probably a wise decision.

Marty - check out Fig. 3 in this paper:

(link removed)

It's got the (general) relative humidity of the CONUS. California coastline might be better than the west side of the Sierra Nevada. But air conditioning is probably a bigger influence.

 

[guitarbuilder]

Nick,That's an interesting map on fig. 3. Thanks! I can see why domestic wood is kiln dried to 6-8% MC as 90 % of the states are in that range. When I taught woodshop on the Texas Gulf coast, we'd get our wood from Dallas and the boards would warp like crazy in no time.
I'd imagine any serious woodworking on the humid coastal regions needs some constant A/C or dehumidification there to help control things.

 

[Shepherd]

I was starting to get it, but then you lost me again. What you said, I had to look this up, a big word for me, is an oxymoron. Wood and shrinkage. That doesn't click. Does interplay come before or after foreplay? I understand cold water shrinkage but longitudinal, radial and tangential sounds like your giving a gps location. Now my head really hurts.

 

[Arlo]

Ol Piney is as flat and sound as the day I bought it from ya Marty. All it has ever had is Howard's Feed n Wax on it for a finish. It spent over a week in California and didn't show any sign of cupping or warpage.

I live in a place that defies description when it comes to climate.

 

[otterhound]

NickJD , you are right on the money once again . As far as spending a week in Calif. . On a finished piece , it would likely take longer . How much time was spent outside of the controlled environment called the case ? I'm just attempting to back up some very good info . Do with it what you will . May all of your necks stay straight and your bodies never cup .

 

[boris bubbanov]

May all of your necks stay straight and your bodies never cup .

Sounds like an Irish blessing!


And may all your Baja Tele neck pickups be twisted.

 

[Nick JD]

Does interplay come before or after foreplay?

Foreplay? Never heard of it. Sounds like an oxymoron.

 

[otterhound]

Sounds like an Irish blessing!


And may all your Baja Tele neck pickups be twisted.

Sorry Boris . I can't be Irish , I don't drink .

 

[Al Watsky]

I was concerned that the OP was about building with non seasoned timber.
Seasoned pine is stable.
Kiln dried then sticked and stacked. The longer the better.

 

[ramseybella]

Well................. I'm in the high desert Southwest. If someone wants to send me a one piece pine body I'd be more than happy to give it the dry climate test. Probably be best to continue the testing for several years.

No kidding but lately with the rain it has been a little humid in Santa Fe?

 

[guitarbuilder]

I was concerned that the OP was about building with non seasoned timber.

There are about 50 or more one pc pine bodies out there from the same source in TDPRI land and I was just trying to get some feedback from them on the flatness (like Arlo provided). It's all good information though.