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Humidity or lack of and cross shafts
Posted: 10 Feb 2003 10:01 am
by Jim Smith
I hear of a lot of people having trouble with cross shafts binding on all wood body guitars. I don't think a lot of people know that wood will absorb or release moisture even through most finishes.
Sometimes the price we pay for having good looking and sounding guitars is the inherent instability of wood. Any thoughts on how you adjust and or compensate for this swelling and shrinking?
------------------
Jim Smith
jimsmith94@attbi.com
-=Dekley D-12 10&12=-
-=Fessenden D-12 (coming soon)=-
Stereo Steel rig w/Boss GX-700
IVL SteelRider w/JV-880
Posted: 10 Feb 2003 11:56 am
by Dan Dowd
Well a friend of mine built a pedal steel and left .030" clearance on the cross shaft front to back and his pedals were hanging up because of the reduced humidity in the winter. I discussed this problem with Jerry Fessenden and he said the solution on his guitars is to loosen up the 4 screws that hold the aluminum strip that cover the shafts on the rear of the guitar a turn or 2 to free up the cross shafts.
This is a common problem because wood is a hygroscopic material, meaning that it readily takes up and retains water. It always contains water and exchanges water vapor with the air. For example, wood will adsorb water when the relative humidity is high, and release it when the relative humidity is low. Wood swells as it adsorbs water and shrinks as it releases water, so both its moisture content and dimensions are controlled by the relative humidity of the air. Relative humidity is defined as the ratio of the water vapor pressure or water vapor content to the saturation vapor pressure or the maximum vapor content at the temperature of the air. The saturation vapor pressure in the air varies with air temperature: the higher the temperature, the more water vapor it can hold. When saturated the relative humidity in the air is 100% RH.On a 30 degree F day with an outdoor RH of 60%, the relative humidity indoors can drop to levels as low as 15% when the air is heated to 70 degrees F (as the air is heated it expands giving it the capacity to hold more moisture. If moisture is not added to the air as it is heated the RH level may drop considerably). If the outdoor temperature is 10 degrees F, the indoor relative humidity may fall to 8% or less. These are extreme levels of dryness. Since warm air can hold more water vapor than cold air, the relative humidity of the air can be changed by simply changing its temperature. If in the winter, outside air at 20 degrees F and 65% RH is drawn inside and heated to 70F without humidification, its RH drops to about 10%. In summer, outside air at 70F and 60% RH flows into a basement at 60F causing an increase in RH up to 82%. This can also cause a gap at the end plates/wood cabinet when the humidity gets low.
I would think this humidity/wood problem could also effect regular guitar necks especially the type that have a truss rod in them.
I toured the Gibson Custom Shop in Nashville a few weeks ago and they had a controlled environment and maintained a specific RH at all times which consisted of water spray heads mounted at the ceiling thruout the facility and were controlled by a RH device.
Posted: 10 Feb 2003 12:30 pm
by Jon Light
Hey Jim--how does the Dekley handle humidity change? I would imagine it would be pretty impervious? And as to your original statement--are mica guitars more stable even though the undersides are nekkid wood?
The Carter also has several screws that when loosened allow you to slide the rear apron in or out to accomodate the expansion/contraction cycles that will bind up the cross-shafts.
<FONT SIZE=1 COLOR="#8e236b"><p align=CENTER>[This message was edited by Jon Light on 10 February 2003 at 12:30 PM.]</p></FONT>
Posted: 10 Feb 2003 1:10 pm
by Jim Smith
That's a great explanation Dan, thanks!
Jon, Dekleys have an aluminum frame so they don't have that problem. Also the top is mounted in a U shaped channel with a gap on the ends and sides specifically to allow for expansion and contraction.
I'm no finish expert so I don't know if Formica helps or not. Intuitively I would guess the Formica and glue seals moisture better than lacquer or polyurethane, but maybe it doesn't make any difference if the other side is exposed.
Posted: 10 Feb 2003 6:32 pm
by Donny Hinson
Really, as per the above discussion, there is no way to eliminate the effects of moisture on wood, other than to completely impregnate it (such as in Pakka-wood). However, doing so increases the weight, and may rob the wood of its natural musical properties. This is most likely why MSA went with CF on their new steels. Steels made with wood have a beauty and sound all their own, but carry along with them their own set of peculiar problems, namely, their inconsistancy in environments with varying temperature and humidity.
Now you know one of the main reasons for a typical steelers complaint, which I'm sure you've heard at one time or another, "It sounded and tuned good last night, but tonight I couldn't get a decent sound, and it wouldn't stay in tune, no matter what I did!"
Blame Mother Nature...and her lovely wood.
Posted: 11 Feb 2003 2:38 am
by Ricky Davis
Gosh Jim; I've played over 50 different all Wood pedals steels...and I've never heard or had that problem???
what??
Are you saying that the wood underneath expands into the cross shaft enought to where they don't turn all the way???
If so and that is the problem...it's a good thing all the good shobuds were round cross shafts or rack and Barrel...ah....ha.
Ricky
Posted: 11 Feb 2003 6:04 am
by Jim Smith
Ricky, I haven't played one with that problem either, but I get all kinds of emails, and that is one of the questions asked.
I think older Sho-Buds and other guitars with the cross shafts mounted in L brackets on the bottom of the guitar don't have the problem, but guitars with the shafts mounted in the wooden side rails do. I think this was the reason Emmons came up with the cross brace in the middle of the guitar.
Posted: 11 Feb 2003 6:20 am
by Richard Gonzales
I just got through reworking a wooden formica covered guitar. All of the shafts were binding due to the wood swelling. The square shaft end where it makes a transition to the round was pushing against the bronze bushing, where in turn the bushing was causing pressure on the metal strip that retains all the shafts. I removed 1/16" from the length of the bushings and now all the shafts rotate freely. I guess you could loosen that metal plate, but I wanted a permanent fix.<FONT SIZE=1 COLOR="#8e236b"><p align=CENTER>[This message was edited by Richard Gonzales on 11 February 2003 at 06:20 AM.]</p></FONT>
Posted: 11 Feb 2003 6:38 am
by Dan Dowd
Jim, way back in 1958, I built my 1st pedal steel and used rosewood formica to cover it,because I was not a good wood finisher back then. And if you closed one eye and stood back ten feet it looked like real wood. It was a tripple neck with two pedals on the front neck. The guitar was built in my basement in Buffalo NY during January and Feburary and not heated much. I did a great job with the formica and the edge seams blended great. Then came summer and the humidity. All of a sudden I noticed a gap in the seam between the top and front. The gap was aprox 1/16". Back then I had no idea of what has caused this and thought I did a poor formica job, inspite of how good it looked when I built it. I might also add, Buddy Emmons played that guitar when he was doing a show with E Tubb and came in to the club I was playing at. I was shocked at how great my formica guitar sounded and how great he played the Four Wheel Drive on it. I could never make it sound that good. Just an added note, that it was at this time I learned that the sound is not in the guitar,but in the player. Back then Sho Bud was getting started and the pickers in my area just had to have one so they could sound like Buddy,but of course they never did and sounded like they did on their old guitar.
I don't think you can completly seal wood to eliminate the humidity problem unless you play in a controlled sterile inviroment. Back then my steel would sit in the trunk of my car from sunday thru friday thru winter and summer and I would notice the gap would grow and shrink. Maybe carbon fiber steels will eliminate this problem, but I would be willing to bet there will be some other, unknown at this time, problem to rear its ugly head in time
Posted: 11 Feb 2003 7:01 am
by Bill Hankey
Jim S.,
I feel that the reader could be drawn into a wide range of speculation concerning moisture absorption, whereby the cumulative effects are not that drastic. Even the pioneers of New England depended on the effects of expansions, and contractions. If the horse drawn wagon builders could return, and share their knowledge with present day craftsmen, they would bring with them valuable information. My point is this- the aforementioned problem of binding, I.M.H.O., goes far beyond water absorption, due to its limitations.
Bill H.
Posted: 11 Feb 2003 10:24 am
by Ricky Davis
OH I got ya Jim> Like the Emmons cross bars mounted in the aprons wood...and it binding??? Oh yes...I can see that happening for sure.
Thanks.
Ricky
Posted: 11 Feb 2003 10:42 am
by Dave Robbins
I had a 70's model Sho-Bud with beautiful maple finish. I used to leave it set up in my basement/music room. One year we had a lot of rain and as a result developed a leak into our basement. My Sho-Bud sat humbly there under it's nice leather cover. I went down to play it one day, pulled off the cover to find EVERY INCH of the finished cracked! The body had drawn moisture and shattered the finish like glass. Didn't bind up, but there wasn't any need to ever take it out and play it again. My Emmons was there too. No bind, no falling out cross shafts, and no cracked finish. It was even still in tune. That's what I have played ever since.
Dave
Posted: 12 Feb 2003 9:01 am
by Bill Hankey
Jim S.,
If you were to set out to create a scenario with a likeness to Dave's, it would be akin to trying to pacify a bobcat, after spooking its intended prey. I think that with the foreknowledge that the steel was subjected to a damp area, I would have checked its external finish many times before that much damage occurred. One must treat steel guitars as if they were fine furniture. Protect them from sunshine, dampness, spilled drinks, cigarettes, etc. when away from home. Their cases would offer protection, by locking out the purported moisture to some extent.
Bill H. <FONT SIZE=1 COLOR="#8e236b"><p align=CENTER>[This message was edited by Bill Hankey on 13 February 2003 at 06:28 AM.]</p></FONT>
Posted: 12 Feb 2003 9:13 am
by Jim Smith
Very true Bill.
Speaking of cases, one little trick I have done for 30 years is to keep one or two of those little bags of desiccant that come in boxes of electronics, etc. in my case. I don't know if they are enough to help, but they don't hurt!
FYI, desiccant is calcium oxide or silica gel, that has a high affinity for water and is used as a drying agent.
Posted: 12 Feb 2003 10:36 am
by MARK GILES
Having been involved in woodworking and instrument building for nearly 30 years, including over a thousand steelguitar bodies, I can attest to the fact that wood does swell and shrink with the changes in humidity. Dan explained it pefectly in his post. Mica will slow down the process, but will not stop it. Nor will any other finish. It is not uncommon for a steel guitar body to expand or contract .030" to .090". I have seen them move .125" although this amount is rare. Even die board and pakka wood bodies expand and contract, only not near as much, so it is not as noticeable. Most guitars are of good design so that the moving parts move freely in spite of the expansion and contraction.
Posted: 12 Feb 2003 6:34 pm
by Jim Palenscar
This thread is attesting to the complexity of properly setting up a steel. While we'd all like to set them up so there is virtually no slop or play anywhere- especially in the crosshafts~ it is not done that way on most guitars by those in the know as it will create problems down the line when nature takes its course on the cabinet. However- the caveat to this is that setting them up loosely, while preventing this, can cause other problems such as causing the crosshaft to torque a bit more in the loose bushing and this gives rise to tuning problems. To check this turn your ax upside down (or crawl under it with your favorite "creeper" like I do)- push on a pedal- check two or three along the course~ then push harder and watch the crosshaft get a titch more "cocked" in the bushing and listen to the note. A fine buider whose recent passing was a loss to us all~~Dick Miller~~I believe used to put bearings on these surfaces to help control this in the Bethel Guitar. Just a thought for those of us who have little else to do
.<FONT SIZE=1 COLOR="#8e236b"><p align=CENTER>[This message was edited by Jim Palenscar on 12 February 2003 at 06:35 PM.]</p></FONT>
Posted: 12 Feb 2003 11:00 pm
by Dave Robbins
Bill Hankey,
I'm not sure I understand what point your trying to make.
As for having any foreknowledge of potential dampness, the area that the Sho-Bud was set up in was not damp prior to the incident, had carpet covered floors, stereo equipment, my office, and ceiling to floor drapes, all that I would have preferred not to have damaged. The area also contained my amps as well as an upright piano, and the afore mentioned Emmons steel (which had no damage aside from the high water marks on the legs!). The high water came upon us way too fast to have moved anything had we any idea of what would happen. The old Sho-Bud was a favorite of mine, which I got brand new around '70. The cover I kept over it was indicative of the care I took of it "constantly" to protect the finish.
By the way, I still have the guitar.
Wood finishes are pretty "regardless" of the brand. Then again, so are coffee tables.
Dave
Posted: 13 Feb 2003 12:03 am
by Bill Hankey
Mark G.,
Are you aware of the fact that long ago, woodcutters whittled out ash wood axe handles, with a hatchet, and finished them by scraping their surfaces with razor-sharp broken glass pieces? After the handles were fitted into the axe-heads, wedges were driven into a split in the center of the handles. They soon learned that moisture content in the wood attributed to a tighter fit of the handle in the axe-head.
Soaking the axe-head overnight in a pail of water was a proven method to insure that the head would lock tightly on its handle. The swollen wood fibers would allow for many days of cutting wood without the danger of flying axe-heads. No matter how many guitar bodies have been viewed, if any material absorbs water, an enlargement will occur. It is common knowledge, and a natural experience, that can be observed on a daily basis. Swollen ankles would be an example to exemplify the truism.
Bill H.
Posted: 13 Feb 2003 2:30 am
by Bill Hankey
Dave R.,
In all due respect, please allow me to at least give some thought to what you have stated. Everyone should have the right to examine such phenomenalistic occurances that are rare; indeed. Interests peak rather suddenly, by those of us who are aware that many other strange happenings, need to be thought out, due to findings that were unrelated to the most obvious conclusions.
Bill H.
Posted: 13 Feb 2003 8:16 am
by Bill Fall
I'm no engineer or craftsman, but it seems to me that a simple resolution to this problem would be for builders to have the cross shafts mount on one end into holes in curved flat-spring mounts. Any expansion would then be absorbed by the flat spring, instead of compressing against the cross shafts.
Posted: 13 Feb 2003 1:50 pm
by Dave Robbins
Bill Hankey,
in resonse to your above posting: We're talking about a musical instrument. Not axe handles.
In response to your following posting: My compliments on your attempt at literary expression.
Dave
Posted: 13 Feb 2003 6:09 pm
by Jim Bob Sedgwick
A few of the current guitar makers, Williams and GFI have their cross shafts mounted in Delrin bearings. Problem solved.
Another big advantage, Delrin does not require lubrication ( Delrin is like a Teflonized plastic, used by space engineers, ie: NASA. Another advantage is Delrin does not wear out due to friction.
Posted: 14 Feb 2003 12:11 am
by Bill Hankey
Dave Robbins,
I'm still insistent upon analogizing for reasons of adaptiveness, that quite often suggest that most "problems" can be dealt with effectively.
How many times have you "grabbed" a shopping cart at your favorite store, and soon discover that it has a "mind" of its own? You may want to turn to the left, but it pulls you to the right. Don't blame the cart! Blame whomever is in charge of maintenance. A steel guitar is not different in a sense. Automobiles are excellent analogies for the purpose of pointing out neglect. Do you ever recall actually witnessing proper lubrication of emergency brake cables at your favorite garage? Again, the steel guitar's "needs" can be overlooked in a similar manner.
I think the best way to describe a steel that has the "binds", would be to say, the instrument has developed "arthritis", from long term neglect.
Bill H. <FONT SIZE=1 COLOR="#8e236b"><p align=CENTER>[This message was edited by Bill Hankey on 14 February 2003 at 02:46 AM.]</p></FONT><FONT SIZE=1 COLOR="#8e236b"><p align=CENTER>[This message was edited by Bill Hankey on 14 February 2003 at 02:53 AM.]</p></FONT>
Posted: 14 Feb 2003 10:52 pm
by Dave Robbins
Bill H.
I will agree with you that "problems" can be dealt with, only if one has the patience.
However, "neglect" can not be blamed for design flaws.
On the other hand, "neglect" can be an issue if one spends too much time on exchange of useless dialogue, when one's time could be better put to use practicing said instrument.
Dave
Posted: 15 Feb 2003 12:21 am
by Bill Hankey
Dave,
I truly appreciate the gentlemanly qualities that you have shown throughout our exchanges in this thread. However, I must ward off any such notion that my steel guitar practice is limited, due to the time spent on the forum. I've been checking out my old records for about two weeks, listening to hear steel guitar intros, and breaks that determines whether or not I'll be selecting them for replay. As for practicing, whenever I hear a phrasing, or something appealing, "that turns my head", I check it out on my homemade steel. Lately, after installing my new short pedals, which are mounted between the A&B pedals, trust me, I have given the steel a work-out. I can appreciate your reminder to stick to practicing.
( My apologies Jim, for swinging too wide, and out of your thread.")
Bill H.