Humbucker Screw Installation Jigs

[kayakerca]

I think I'm about 100 years away from figuring out all the little things that will help with my pickup making. I had an order for a set of gold humbuckers from a couple of my models. I have always found it a challenge to put the screws in the bobbin such that they are a perfectly aligned and as straight as they can be so it isn't a colossal struggle to get the cover to fit over them without any misalignment torquing the top of the cover a bit or denting the edge around the screw hole, and just making it all round ugly to keep square and the like. I didn't want to screw up the nice gold covers on this job, so I had to wrap my head around how I wasn't going to let that happen. Like is the case a lot of the time, it came to me about 4:00 a.m. when I should have been sleeping. humbucker screw installation jigs! ! ! They worked perfectly. 1/2" thick is just right to give a nice long start for each of the screws. I rest them on top of the screw side bobbin and drop 710" X 195" rod magnets into the holes of the jig and through to the bobbin to deep them aligned, removing them one by one as they are replaced with the screws. Worked great as the covers fit over better than I have every had them fit over before. I'm sure everyone here has 10 better ways of doing it, but this one worked out nicely on my bench!



I used MDF for the test, but I'll make a couple more from 1/2" Delrin as soon as the MDF set wear out. Happy boy. No sleep, but a happy boy. . .

[Jim Darr]

Jim,

I am a little confused about your problem. Is is that the screws thread the bobbin at a angle? I just pre-tap the thread in the screw side bobbin to match the Fillister screw I am using. They go in straight every time. No problem with that method...been doing it for years.

To protect the coil when actually installing the screws I use flat blade screw driver bit with a nylon sleeve to prevent the screw bit slipping off and marring the bobbin.

Is the problem this or something else?

[big_teee]

I've never had that alignment problem.
The alignment block is however a good idea.
I tap the screws with a tap, I do try hard to thread them straight.
I run the screws out a ways before I put the cover on.
Solder, then carefully run the screws back down.
T

[jack briggs]

I just drive them in. the holes align the screws - never had a problem.

[kayakerca]

I install them in with an electric driver but somethings they are the smallest bit off square and a little tough on the cover which is why I thought to try a jig. Worked well and was faster than me trying to keep the screw tracking straight with the driver. I pot the coils, but not the assembled unit. Since I melt wax into the cover and press it on and let the wax set a bit before soldering the cover, it's nice to have a cover that slipps over the screws before the wax set.

Thanks all for the input.

[Alberto]

How can they be off square if the bobbins have holes to let the screws get into, just like a mold? I once had a similar problem but I was tring to fit a 49.2mm cover in a 50mm bobbin...

[kayakerca]

How can they be off square if the bobbins have holes to let the screws get into, just like a mold? I once had a similar problem but I was tring to fit a 49.2mm cover in a 50mm bobbin...

I have find that the screw will cut a thread through the hole even if it is a little off perpendicular. Just like if you are tapping metal, if you are off perpendicular, the tap is going to cut off perpendicular. When I go to seat the cover over the screws, one or two would be a little to the left or right of a perfect fit into place. I prefer to pot the coils before assembly and then just melt some was into the cover before installing it. If I have to struggle with getting the cover past a couple of off perpendicular screws, the was solidifies and doesn't seat to the bobbin tops the way I planned. I have tried backing the screws off so the cover slids over easier and seats, but I've had a couple where when I drove the screws back down, one of two screws actually flexed the edge of the cover. I've only done a couple with the jig, but it seems to help a lot with keeping the screws perpendicular. As well, it only took ~ 5 minutes to CNC the pair and it seems to have solved my problem.

[Alberto]

Got it! Never had this issue though...

[big_teee]

I had some covers with tight holes.
I was using SAE fillister head screws.
I ended up taking a chain saw file and carefully enlarged the holes.
I think they were the gold mojo covers.
T

[kayakerca]

I had some covers with tight holes.
I was using SAE fillister head screws.
I ended up taking a chain saw file and carefully enlarged the holes.
I think they were the gold mojo covers.
T

Definitely Mojo gold covers and hardware on the set this week. Definitely a pretty snug fit.