Pull Rods-Slack or No Slack?

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Lee Baucum
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Joined: 11 Apr 1999 12:01 am
Location: McAllen, Texas (Extreme South) The Final Frontier

Pull Rods-Slack or No Slack?

Post by Lee Baucum »

I set up all the pulls on my guitar with no slack in them. In other words, once you start moving a knee-lever or pedal, the pull starts raising or lowering the pitch of the strings. I hate sloppy knee-levers that can wiggle back and forth.

I have read that there should be a bit of slack, or space, between the pull finger and the tuning nut. What is the purpose of this slack? If there is no slack, or space, (like on my guitar), can temperature changes cause the pull rods to shrink enough to actully pull the string out of tune?



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Lee, from South Texas
Down On The Rio Grande
Pete Burak
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Post by Pete Burak »

One purpose of the slack is so that when you tune a pedal-down raise, you don't inadvertantly cause the open non-pedaled note to go sharp.
To see this effect, run your steel through your tuner, and with no pedal depressed, start tuning (like you a sharpening a raise)at the endplate and see how fast the open note is effected.
If you are not aware of this you can get yourself into a tail chasing nightmare.
Slack is also used in some cases to control timing of multiple pulls on a given pedal.

Keep at it because you will really get a good feel for how your changer works with regard to the many parameters it controls.
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Lee Baucum
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Location: McAllen, Texas (Extreme South) The Final Frontier

Post by Lee Baucum »

Hey Pete! I know just what you're talking about. It can be a real mess if you don't have enough travel in the pedal or lever. Actually, what I've done is tuned all the raises and lowers using the pedal stops and the knee-lever stops. (At least, they're real close.) The nylon tuners are just used for fine tuning. I was just curious to know if keeping everying thing that tight could cause other problems.

Lee
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richard burton
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Post by richard burton »

I wouldn't like to chance having no slack in the rods, especially if the steel has an ally neck. If the wobbly knee levers are a problem, put a very light spring (or elastic band) on them, to pull the lever in the same direction as it moves when actuated. This should take out any slack. The weight of the pedals normally means that there is no backlash in the pull rods.
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