We were assembling a guitar this week for a photo shoot to feature a couple of new titanium components, until we realized that the plain black bobbin humbucker pickups just didn’t match with the aesthetic vibe. Nickel silver is a fairly good color match for polished titanium, so we decided to class up these pickups with some nickel covers. Never tried this before, but figured that we might as well document our learning process and maybe someone might find it useful. Or funny.
First step: Don’t forget to check that the cover holes actually line up with the pickup screws!
Plenty of opinions on the internet about installing nickel pickup covers, so how to go about it? Wax potting? Silicon adhesive? Tape? We started by imagining the parts in mechanical terms, where the pickup is a motorcycle chassis, the cover is the wheel and the sound energy in the air is the spring. Might we imagine squeal as uncontrolled free harmonics (having no shock absorber) and those imported ‘baked in wax until dead’ pickups as a solid hardtail suspension? Then, we might be looking to find just the right amount of compressive resistance to tame the excess harmonics but not kill the good overtones.
In typical RockRabbit fashion, let’s try a bunch of stuff and see what happens! First question: How much clearance space is there between the nickel pickup covers and the top of the humbucker? Assuming that there is bound to be more space in the center than near the edges, let’s try a piece of the double sided masking tape that we use to attach templates in the shop, which measures about .007” thick. A small piece in center seems to fit without interference.
Next, we have some double sided Gorilla brand tape. It is super sticky and somewhat squishy, measuring .040”thick and compressing to .020” under my dial calipers. As you can see, even with a bit of clamping the Gorilla tape is holding the nickel pickup cover away from the humbucker by a noticeable distance.
At this point, we were reminded of installing a heat sink on a CPU. Placing a small bead of thermal compound on the center of the die and then letting the heat sink compress it to its own level seems like a way to use the minimum amount of sticky material to get the job done. Two sticky materials that came to mind were: Blu Tack and Silly Putty. Couldn’t find actual ‘Blu Tack’ brand, but did find what looks to be the same stuff in white. Not sure where to even find Silly Putty anymore, but it would have the advantage of pulling images off your favorite album cover. Then we could argue the sonic merits of having Clapton on the pickups or if Santana would better complement our tone.
So, let’s try our white ‘Blu’ tack. Placed a piece of clear tape (about .002” thick) upside down on the humbucker and then cut a sliver of the white tack and worked it with my fingers down to what looked like .015” thick or so.
Some light clamping force and the white ‘Blu’ tack compressed nicely.
And removing the nickel pickup cover, we can look underneath and check out how the white ‘Blu’ tack spread.
Looks like this might be worth a try. So, to do this for real, we taped the pickup with our regular clear packing tape that is pretty sticky and measures about .0025” thick, then cut the extra tape around the edges with an Exacto knife. Cut another piece of white ‘Blu’ tack and placed in the center.
Clamp and solder.
And there is our very first experiment installing nickel pickup covers. As soon as we can get the neck ready to go, we’ll get the guitar strung up and listen to how they sound. Giving the cover a tap test, the area directly over the white ‘Blu’ tack does sound ‘solid’. Like the difference between tapping a solid guitar versus a hollow body guitar. Not sure how or if that will equate to any squeal resistance until we can give these a proper play. Until then, love to hear people’s ideas and comments.