I'm experiencing very vexing problems with my Fender 400:
Using Sneaky Pete's setup, whenever I press pedal 8 (E to Eb on E9th), my second string returns very sharp. Pressing pedal 7, which raises that string a whole tone, brings it pretty much back to pitch.
This is driving me nuts and I have some shows coming up.
Joel - back off both the 7 and 8 pedals' turnbuckles, and possibly the pedal rods as well (i.e. lengthen them). That's the most common reason if nothing is physically hanging up. Let hem have a bit of slop, and if it solves the problem slowly increase the tension to find the "sweet spot".
If that doesn't do it there's a physical issue - either pulleys catching, a stuck disc on the large pulley, or a changer finger hangup...or, especially if they have been replaced, a weak return spring.
Make sure that "at rest" all the fingers line up *exactly* - if one (or more) are a bit out in front of the others, it indicates an overtightened turnbuckle or pedal rod. When I built my first one I knew NOTHING about steels, and that problem drove me nuts - then I posted a picture and got about 7 answers in 5 minutes!
No chops, but great tone
1930's/40's Rickenbacher/Rickenbacker 6&8 string lap steels
1921 Weissenborn Style 2; Hilo&Schireson hollownecks
Appalachian, Regal & Dobro squarenecks
1959 Fender 400 9+2 B6;1960's Fender 800 3+3+2; 1948 Fender Dual-8 Professional
Yeah, common problem for newbies. The fingers should all be against the stop-plate with no pedals activated. If they ain't lined up in a nice, neat little row, you're in for trouble.
b0b wrote:Over-return on the lowers is a common problem on all pedal steels. The effect is called hysteresis.
I don't know how this works on modern pedal steels because unfortunately I don't have one.
My old Multi-Kord can be relied on to do this, and that makes me think may be one reason some believe they won't stay in tune.
When I'm tuning the pedals on my Multi-Kord I always tune it a little low with the pedal depressed. I usually can get it right the first time and when I depress it again and let off, the string being tuned will then come back to the correct pitch. My Multi-Kord stays in tune very well if I do this. Otherwise it won't.
I think I found the problem last night: the cable on my 8th pedal needed a re-soldering job. I was at my wit's end and tried this as a final idea and it seems to have worked so far...
For the sake of posterity, please correct your post. It says "whenever I press pedal 8 (E to Eb on E9th)"
It appears you have no E to Eb change on pedal 8.
(I think that should be B to A# on E9th, so as to agree with your diagram, re: pedal 8.)
Also, a bad solder joint on a cable will never make a string return sharp (that is, unless it had so much solder at the changer end it was binding another cable). Even if the cable breaks, a change won't return sharp, since spring tension is what pulls the finger back into position, and it'll do that even without a cable.
I rather suspect your problem was just a turnbuckle that was over-tightened.
I meant that pedal 8 does the same thing on my B6 (on the high root) as the E to Eb does on an E9th guitar. I did this assuming that *most* forum members don't play an 8 string B6th guitar, so I figured the comparison would help everyone know what I meant.
As for the solder issue on the cable, the cable was a home-built one that I had to make because I was out of original parts...it turned out kind of crummy.
My post about fixing the problem was a bit premature (apologies), because fixing the cable did help the feel of the pedal, I did have to flush out the changer mech yesterday with naptha and re-lube it as well.
Otherwise it won't. 
