yep thats the stuff, might be an idea to get heatshrink for the ends as well if you dont already have it.
Hood

Hey Lee,
    A couple of other things that may help or you might want to check. Your connections on the geckos. The blue connectors push on to pins. You can pull them off and rotate 90 degrees and push back on. I have seen some blue connectors that had a bad connection. Also, twisting, (braiding) your wires may help and if you have to cross another wire, run it across as close to 90 degrees as possible And try not to run them parallel to one another.

Brett

Nope dont put the connectors on the other way, I got told off from Mariss for doing that Seems they are only meant for the way in the pic.
Hood

EDIT
just been talking with a redneck and he says he had bad connectors so give them a go round the 90degrees like he said, anythings worth a try especially if its free

I would contact Gecko and ask for new connectors. They are real good to work with and will most likley get them right out. A good bunch to work with.

Brett

Thanks a bunch, Guys.
I did check all the blue connectors. They seem to be fine for continuity. If I turn these around, they don't lock in and the cover doesn't fit right. They don't plug in as far either.
I suspect that if swapping the connectors out has fixed someone's issue, they may have had a noise issue and the movement and different placement of the wires cleared up the issues with noise.

At any rate, just moving a bad drive to a good drives location and using the good drives wiring stopped the issue it was having. It purred just as the good one did.
I don't think it's that actual connections. All the wiring is nearly a short as possible and pretty much identical.
I think the noise issue has to be the trouble. If it were a ground loop, the the stable drive wouldn't work right either.
I wasn't even aware that the blue connectors came off before this though. Looking at them closely, they are a nice little bit of diseign and engineering as well. Double sliding dovetails. Very cool. 
Thanks Guys.

Well, Guys, even after the shielding, I still have the problem.
Z runs perfect. The other two run pretty good, but will go both directions using the same arrow key.
Here is a photo of the shielding in place.
http://leestyron.com/cnc/cb4.jpg
My site is down for the past few minutes but should show up soon.

Now I am nearly at an end of the battle with this case and configuration. I have no clue what might be going on now.
I have swapped everything I could think of including computers, keyboards, drives, motors, cables, BOB's, 5 volt sources, switches, PPort cables etc.
I have swapped pin settings on the BOB and matched them up to Mach. All three motors have the same settings and then different settings from very slow to fast. No difference. I still get bidirectional movement from one arrow key. I get this same kind of movement regardless of which arrow key. Both on X and Y.

I have a question. The 470 uf caps. Gecko says to use these if the PS is more than a foot from the drives. They are right at a foot. Would it hurt anything to remove them and give it a whirl? I am thinking it would be okay. I am still just boxing shadows n this.
This is all before I even get the THC 300a turned on and the plasma going. This could really take some time. 
Thanks for any suggestions at this point.

I did remove the caps and there was no change.
I am officially out of things to try.
The only things I didn't shield are the 12 volts to the fans from the computer PS. I did shield those switch wires though.
I didn't shield the 120 v ac running to the BOB and the switch either, but I was getting the same type thing with just a standard BOB and using the 5vdc from the lab supply, so I am kinda ruling out interference from those.
They are also running in the very front of the case and not really crossing any of the drive and step/dir wiring.
Just really odd stuff here. For me anyway.

Perhaps its time to try a completely different case.

Do you have the shielding grounded? I see some of it is but cant tell if the rest is? Also I think it is best to have all the shielding grounded to the same point but maybe I am wrong there.
Hood

Now you see there! I hadn't even thought about that.
The shielding that was originally grounded through the cabeling is grounded. The rest really isn't. Perhaps intermittent at the back where I have the clamp on the three motor plug recepticles, but not actually screwed down for sure.
I will try that and thanks a bunch.

Try and ground at one point, think its what they call star grounding.
Hood