Copper Grounding Bus

[Ron Worley]

Tim-

I may have another source and Allyn said that he might have some... but in the end, I may have to suffer Ampwares..again..

Thankfully, my missus doesn't seem to mind me doing this stuff...keeps me out of her hair, I suppose....

Alan- Thanks very much for the grounding scheme... Do you use pots that have an insulating collar that prevents grounding against the chassis, and where do you get them???

The scheme makes sense, but I won't kid you that I need to read up on star grounds and Aiken's stuff to really get it sussed..

Although this is technically my first real build, I'm a (rusty) BSEE, and I've been repairing Fenders for several years. I have been very anal about lead dress, etc, and baring any real f*#kups, I should be relatively OK. I have read others mention the shielded on the volume pot and a V1 grid resistor to tame instability. I must admit that I am not particularly schooled on tweaking, so I have been taking copious notes from the board. Part substitutions are where my lack of theory mastery really shows.... I figure that's part of the learning process doing this whole Wreck thing... and I love it.

Again, many thanks for sharing your experience with a Noob!

Ron

['67_Plexi]

In the scheme I mentioned, it really doesn't matter if the back of the pots are grounded to the chassis or not, they are insulated from the pots terminals by design. The idea is not to connect any pot terminal to the chassis including the back of the pot, except at the correct chassis ground point.

[Ron Worley]

Alan- I understand- what insulated speaker jacks do you use to keep the speaker ground off the chassis????

Ron

[v846]

I've been looking for a source other than Ampwares for those the grounding lugs with no luck so I bit the bullet and ordered from them, just got them today and the delivery time was two weeks. They look OK though the hole for the wire is drilled slightly short of the back of the pot, dremel will take care of that..

[Ron Worley]

Allyn didn't have any lugs, but I have another source that is looking good. If that craters.... well, it's off to Ampwares for another exercise in frustration...

Ron

[drz400]

Bump-- No other inputs guys??

Ron

You can mount 3 isolated stand offs and run the buss wire on that
Only connect to one place at the chassis or put the buss on the board

['67_Plexi]

Alan- I understand- what insulated speaker jacks do you use to keep the speaker ground off the chassis????

Ron

Cliff jacks will work for that.

[Luthierwnc]

It isn't the most elegant method but I usually take a piece of 14 gauge Romex and crimp/solder a ring terminal on one end. That is attached at the closest PT lug to the preamp. You can leave some insulation on near the power connections.

This runs behind the pots about 3/4" and is the exact right size to fit in the solder lug of a cliff/rean/neutrik isolated jack where it terminates. Roughing the copper up a little with scotchbrite improves solder flow. Grounds from both the board and controls attach more-or-less along the line according to the related nodes in the power stage (i.e. preamps on one end, main caps nearer the trannie.)

FWIW, Skip

[drhulsey]

... Roughing the copper up a little with scotchbrite improves solder flow...

As does some extra flux painted on

[nickt]

Just ordered a bunch of wire from http://www.wires.co.uk/ - mainly pickup winding but also some 2mm tinned copper for use as a buss - yes 2mm is probably overkill.

This guy has all different gauges but specified in mm.

Hope this helps someone.

[Ron Worley]

Thanks for all the great ideas guys. I like the one using a set of isolated standoffs.... but I have successfully found a suitable grounding lug with a long enough lead...

Ron

[Ron Worley]

And I managed to get enough to share with the Forum. See my post in the For Sale section.

Ron