I am planning an HBD / PRails wiring project on a Semi-Hollowbody. My initial concern is the shielding of ALL wiring. Plans are to use copper braid shielded 4 and/or 2 and/or 1 conductor wire (whatever requirements are needed) for ALL connections to the 4PDT switches, P/P pots, 3 way Pup Selector, and to the output jack. I am going to use Fralin 4 conductor braid shield wire and some 2 and single conductor braid shield from my in house stock. With all wiring being shielded and of course grounded would this be the absolute best way to shield the Semi?
Rune had suggested I encapsulate the entire harness in very fine copper screen and ground it thus creating a grounding pocket environment similar to a Str@t pickguard/wiring cavity being fully lined with foil copper tape.... I was balking at this due to grounded screening accidentally touching 'hot' on one of the 4PDT/PP switches = short. Would be a bad dream to get this harness into the Semi and have a ground screen to hot short issue, take it back out , re-test, fix short/tape encapsulate the 4PDT/PP switches, etc, reinstall.
I have worked on a number of Semi's (challenging, but rewarding) and have confidence the HBD can be shoe horned into the wiring cavity with pre wiring on a cardboard/fiber board pattern/trmplate with the thought of how the harness with be routed into the "F" holes. I usually use the string method to pull the pots and switches into the top holes.
I plan on documenting this entire process for everyone and posting on Gnutz2.
So my questions to all Nutz are: 1. Fully shielded wire throughout Semi-HB would yield acceptable/quietest shielding for the single coils per HBD switching options. 2. Are the exposed lugs on the 4PDT's,P/P DPDT's, 3 way PUP selector susceptible to introducing unwanted noise? Solution ? 3. Should jumpers on switches be shielded as well or = overkill? 4. Are there any better/easier ways to shield a Semi-Hollow than my proposed plan?
Wouldn't it have been nice if they'd sprayed the insides with conductive paint for you before assembly?
Ah well. It is true that any break in the shield is a place for noise to enter the system. Yes, this includes switch and pot lugs. I'd venture to say that a short jumper between two exposed terminals won't make things much worse. Remember also that the switch frame and pot bodies themselves act as (at least partial) shields for the guts of the components.
I think it would be possible to shield those lugs by just wrapping the thing in electrical tape and then like a ball of foil over that. Doesn't add much size to a pot or switch, and still allows you to fish each one individually.
I hate to disagree with RW, but I see the copper mesh idea as a non-starter, for the same reason mentioned by Son-o: How you gonna get it through the f-holes, without twisting, tangling and potentially shorting stuff out?
Ash is right, any component in the signal chain could, in theory, be responsible for introducing some noise. But I wouldn't worry about shielding switches and pots; your plan to use shielded cabling throughout ought to be enough. Longer runs of cable are much more likely to be "dialin' in that noise" than a lug on a pot.
The pickups are really where the (noise) action is, so shielding around the back of the pickups might yield a greater benefit than all the shielded cable. But, as we've discussed before, wrapping the pickup too closely risks altering the tonal characteristics of the pickup (and, probably not in ways that you'd like). You might, though, try a copper mesh "box" that would mount behind the pickup, if you can get it and the pickup to drop in through the hole. I envision this sitting well off the back and sides of the pickup.
And, please do document the build for us. The whole string method thing has intrigued me for years, never done it myself or seen it done.