Crawls Backward (When Alarmed)

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Rickenbacker Pickup Switching Mods: Phase, Series/Parallel

While I had the guitar apart I decided to do some additional electric mods. What the heck.

I'll probably garner the wrath of the Rickenbacker forums, not to mention John Hall. Thou shalt not modify thy Ric! (John Lennon, Pete Townshend and [horrors] Roger McGuinn are excepted).

I mentioned the CTS push-pull pots I procured from Stew-Mac in the last post. I have 2 more on hand, so that's perfect for two more mods.

I'm going to wire it with phase switch and a series-parallel switch. I've written before about my dislike of drilling holes, so these pots are perfect. I'll have three switches total but it will appear to be totally stock, and of course with everything switched out, it will sound totally stock as well.

None of these wiring mods involve rocket surgery. Very common and not hard to do if you know which end of a soldering iron to pound on.

I drew a diagram to follow, but you can use it to follow if you choose to do this. For personal use as a guide, no problem but:

Please, please, please - if you would like to copy this to your site or another site, ask me first! I am quite reasonable about sharing, but this is MY work and as such it has a defacto copyright. I recently found 2 instances where my images were stolen copied and used on other sites - one of them a commercial site. There is such a thing as copyright infringement, and taking images or other content wholesale violates copyright! Just because it's on the internet does NOT mean it's free for the taking.

Rant over, just please ask first. Thanks.

So back to the wiring. The neck pickup is the one that I decided to put the phase reverse wiring on. It's also the one that has its ground lifted when in series mode.

I tried this with the phase wiring 'before' the series wiring and after it in the circuit. I found it was more dramatic as it's shown ('before'). It's a really cool tone with the neck out of phase and the pickups in series. The phase alone is pretty cool also on a 12-string. I have the series wiring on one of my Telecasters, and it's almost too 'dirty' sounding (Lindy Fralin says this too). But here it gives a nice volume and midrange boost.

Obviously, this will work on any two-pickup guitar - I just happened to do it on my 360/12C63.

Here's the phase switch being wired.

I like these pots for the most part. They are a little bulky - I think putting them in something like a Tele with a small control cavity might be a bit tight.

But the basic idea of using a PC board to connect the switch posts to eyelets is a good one. I found that heating the eyelets and putting solder in them, then heating again and inserting the stripped end of the wire in question worked best. I did that instead of trying to insert a wire and solder it in one shot.

As usual with this sort of thing, do as much pre-wiring/subassembly on the switch as you can.

Another thing I did was to unsolder the factory pickup wiring (!) and add a bit of extra wire length on both the hot and ground leads. I did this since the pickup leads need to be able to reach to new locations.

Note that I also used shrink tubing on both leads, and I also put a larger tube (blue on this one) to help support the joint where the leads exit the main cable.

Almost there.

Note the leads in the foreground - I was still testing at this point and had yet to extend the pickup leads.

Better to use test leads and unsoldered connections first to make sure it all works!

I also labelled the switches as well as the selector switch - you're working upside down and backward and it's easy to get everything confused. At least it is for me.

Side note: many kudos to Rickenbacker on their workmanship. Not only are their guitars beautifully made, but the wiring is super tidy Compare that with the nest of wires that my Squier Jazzmaster started with.

All finished. You can see what I mean about the pots being bulky - I had to swivel the treble cap pot a bit to clear the series/parallel pot.

The phase switch is on the neck tone (top in this shot), the series/parallel is on the neck volume (lower left here) and the treble cap is on the bridge volume.

There are lots of new combinations to be had now.

And the best part (for me) is that it looks totally stock from the outside.


Rickenbacker Treble Cap Switch Mod

While I have my 12-string on the bench, I'm going to do some electronic mods to it. This first one is something that was (is) done by the factory.

Older Rickenbacker guitars and basses had a small value capacitor in series with the hot lead of the treble pickup. What this did (does) is filter out bass frequencies and pass treble. The factory offers this as a 'vintage' tone switch on its vintage-style bass - a push-pull switch puts the capacitor in or of the circuit.  The 'stock' value capacitor is .0047 uF (aka .005), I think at 80 volts, but you can use any voltage rating you have on hand.

So I figured I'd give it a whirl.

Now, there is a 'factory' switch for this mod - which is a 330K pot with a SPST switch mounted on it. This is what's used on the bass, and it makes it possible to exactly duplicate the wiring as the factory does it. The guitars use a 250K pot, so 330K should work just fine, and may be a bit brighter.

Now, mind you, you can use any SPST or DPDT switch, or pot with a switch, to accomplish the same thing. I've used switches like that before on some other guitars for series/parallel and phase switching.

But I decided to go ahead and procure the Ric switch. In fact, I got 2.

One of the reasons I did it is that it's sold as having a value of 330K. The stock pots on my 360/12 are 250K, but this is close enough. But I wanted to see if I would notice any tonal difference using a 330K pot instead of a 250K. In theory, as I said above, a 330K might be a bit brighter.

So here are the two pots. One of them is going to wind up in the guitar.

Or is it?

Since 330K is a bit of a non-standard value for a potentiometer, I decided to measure them just for the heck of it.

Well, how about that!

One of them measures 483K - actually within typical tolerance of a 500K pot.


Hey, guess what?

The other one measures almost 500K!

So I have two "330K" pots that are actually 500K.

What the heck?

Are they all like this?

Is this a Rickenspiracy?

At any rate, I don't want to use a 500K volume pot in the guitar, so fortunately I can go to Plan B.

Namely, use one of these fancy new CTS pots with a push-pull DPDT switch on it. I saw them on the Stew-Mac site and snagged a few for future projects. They have them in different values; since I am usually messing with Fenders, I got some 250K pots.

Little did I know I'd use one so quickly.

The neat thing about these pots is that there's a little circuit board with through holes for your wiring - instead of tabs right on the switch. You can see the row of holes just below the pot lugs on the right.

I measured it and, hey, it measures 250K as it's supposed to.

The wiring is pretty easy.

I drew up a little diagram since I sometimes tend to forget what's supposed to go where.

And it gives me a chance to study it and make sure it will work as desired.

I'm wiring it so when the switch is up, the cap is in the circuit. When it's down, it's out.

If you read the diagram you'll be able to trace how it works.

Here's the stock wiring on the guitar.

I usually take a picture like this so if I really goof up, I can use the picture to go back to the way it was originally.

We'll be replacing the bridge (treble) volume control with the push-pull pot. The control is the one on the lower right.

You can but a whole control assembly pre-wired from the factory just like this and plop it in your guitar. Not sure why you'd need to do that, but my point is that there is great parts support directly from Rickenbacker.

Except that their 330K pot measures 500K.

I wired up the switch as a sub-assembly before installing it on the guitar.  It's wired just like the diagram, except the input and output wiring isn't there yet.

I wish I had a Russian PIO cap in this value, but I don't, so I'm using an Orange Drop. Check out the date code! This one's been around a while.

This is one place where you might be able to hear the difference in different capacitors, since the signal passes through it, unlike a tone cap.

Take the original pot out of the guitar, and wire the new one up.

And here's how all the connections are made. I labelled everything on the photo - should be clear what goes where.

One thing about these new pots is that if you use the pot itself as a ground, you'll have to solder to the side of the pot rather than the back. Works fine. I just sanded the pot a bit as you normally would to aid the solder sticking to it, then soldered the grounds to it.

Rickenbacker uses a clever (I think) way of wiring the ground buss. There is a lead that comes into the control cavity from the tailpiece, and that lead goes to the treble volume pot. Then there is a lead that runs to each of the pots in turn, but it doesn't do a full circle.

In other words, it starts at the neck pickup (bass) volume pot, over to the treble volume, then the treble tone and then finally the bass tone. There is no connection between the bass tone and the bass volume. If there were, it would be a ground loop, and potentially hum. But since it's not a full circle, there is no ground loop. Compare this with a stock Stratocaster, which is Ground Loop City.

Then we just bolt the new control to the pickguard.

Then I made another mod!

On a stock guitar, the pointer/indicator lines on the knobs all point downward when everything is turned up to maximum.

On my other guitars, the pointers are up at maximum, so that's what I'm used to. Easy enough to unscrew the knobs so they point up.

How does the mod sound? Well, to be fair, I've only tested it though my little workbench amp. But it does get a thinner sound, especially on the bass strings. I might do some maths and figure out what frequency the 'stock' value capacitor changes and see if it's worth playing with. Something like an .003 would be really thin I'd think.

Guess what? I'm not done with the electronic mods. While I had it apart, I figured I should mess with some other stuff. I'm sure I will offend Ric purists a bit. Stay tuned.


Custom Nut for Rickenbacker 12-String, Pt. 2

In our last installment, we thwapped the old factory nut off our Ric 12-string.

Now we'll make a new one, with different string spacing between the string pairs, to replace it.

This is not a new concept that I dreamed up. (Although I will confess to having the occasional dream about playing guitar.) If you search the interwebs and read guitar forums you'll find complaints and comments about the string spacing on these guitars, or the 'narrow' neck and how it makes it difficult to play cleanly, especially in the lower positions.

There have also been comments about a fix for this - namely, making a new nut with revised spacing.

After pondering all of this information, I wanted to take a stab at making a nut with the spacing between the strings in each pair reduced.

I made some semi-coherent scribblings calculations, which you can see on the sheet on the right.

The one measurement floating around as a suggested spacing seemed to be .070 in. I took that as the widest I'd want to use, potentially, and went from there.

I wanted to space the bass strings wider, and then progressively narrow the spacing down to the high E string pair.

To make it clear which string in a given pair I'm referring to, I'm calling the lower-pitched string of the pair the "fundamental" string, and the higher string the "octave" string. Obviously the B and E pairs are tuned in unison, but that reference will still serve for describing the position of both strings in the pair.

I took into account the string gauges - by using half of a given fundamental string's gauge, along half the width of its accompanying octave string's gauge. Those two amounts added together gave me a width for the string pair. Then I just added the amount each pair should be apart.

This will make more sense in a moment I think. It's not rocket surgery.

I of course had the original nut to take measurements from.

You can see the factory nut on the left, along with the TUSQ blank I would cut the new spacing on.

I also had studied the spacing of the strings while the stock nut was still on the guitar, which gave me an idea of how close the string pairs could be placed together.

I did have some concern that a pair of strings might 'crash' together when played if they were too close. This turned out to be unfounded.

The table below is what I came up with to work from in laying out the new nut. These measurements are in inches; it should be easy to convert them to metric if that's what you're used to working with.

The headings are clear I think. The "Theoretical Spacing" column is the spacing that I calculated to be the smallest amount for the strings, center-to-center for a given pair to be spaced. The "Actual Spacing" column is the amount I used to cut them. (Translation: I was a bit gun-shy and wanted to allow a touch of extra spacing just in case).

And finally, the "Gained in Spacing" column shows the difference between the stock nut and the revised spacing.

String Pair Stock Rickenbacker Spacing Theoretical Spacing Actual Spacing Gained in Spacing
6 - E .0815 .0700 .0700 .0115
5 - A .0805 .0630 .0650 .0155
4 - D .0760 .0550 .0600 .0160
3 - G .0635 .0520 .0550 .0085
2 - B .0630 .0500 .0500 .0130
1 - E .0530 .0470 .0500 .0030
Total .0675

Of course, these spacing numbers are not all we need to cut the nut. And we'll get even more space by moving the E string pairs out further toward the edge of the fingerboard.

The approach I used was just a variation on the way a standard 6-string nut would be laid out and cut.

Normally, you'd mark the two outside strings first, and then lay out the other 4 strings based on the position of those 2 strings. I use the Stew-Mac string spacing gauge to mark the strings' positions, and that's the process you would normally follow.

However, in this case, my lowest string (12th) is the lowest pitched string, as it would be on a 6-string guitar, but the string that would be the standard high E is NOT the highest string on a 12-string.

So I had to adjust a bit to compensate so that I could use the spacing gauge.

I laid out the low E (12th) string as usual - so it would lay just inside the bevel on the first fret. Then I did the same (seen in the image above) for the first of the high E pair (1st).

Then, I marked the second string (the 'octave' high E, although it's tuned to the same pitch) to have a spacing of .0500 as calculated above.

Now I'll use the far left (low E, fundamental, 12th string) mark and inside (fundamental position) high E to line up as the outside strings for the string spacing gauge.

On the right you can see the markings on the string gauge I used to lay out the remaining fundamental string slots.

The arrows show the marking used for the those strings - note that the mark for the high E pair on the gauge uses the inside mark - so that the rest of the string slots will be correct.

It's harder to explain that it is to do. If you're familiar with using the string spacing gauge, it should make perfect sense. You can't use the outside high E as your marker - the rest of the strings won't be laid out correctly.

So then with the fundamental strings marked, we can now mark the positions of the remaining string pairs using the spacing we calculated above.

This picture shows how the pair spacing was laid out with a digital caliper. Obviously, we're working with thousandths of an inch, so of the spacing as cut wound up close, but probably not exactly down to that accuracy.

But it's as close as I could make it.

I stuck this picture in here to show how I held the nut in place as I was working on it. There isn't a groove in the Rickenbacker headstock to hold the nut in place, so I put a clamp behind it as needed.

I tried to cut the slots into the TUSQ blank.

You can see the result. When I tried to get the slot pairs down to the proper depth, the material that is "precision engineered under high pressure and heat" pretty much just crumbled, so instead of two slots, I had one really big one.

The TUSQ also felt pretty soft, like plastic, as I worked it with my nut files.

So I'm not sure what to think at this point. I'm disappointed, because I wanted to try TUSQ. But it didn't work for me on this 12-string nut.

I do have another piece of their nut material and I'll try it on a standard 6-string guitar.

I see that Taylor Guitars uses TUSQ "on all of our guitars" according to Bob Taylor. Maybe they have their 12-string nuts molded so they don't have to cut the slots?

What is TUSQ really? It sure isn't clear from their website other than it "...delivers a rich tone, crystal clear bell like high end with big open lows and a significant increase in harmonic content and harmonic sustain. Increased harmonics equals more richness and character in your tone. Its the difference between a four piece choir and a twelve piece choir singing every time your [sic] play a note."

Which, if true, is even more of a bummer that I can't make a 12-string nut out of it.

Anyway, I had a plan B in hand.

In case I made a major goof with the TUSQ, I had procured a few pieces of Buffalo horn from David Warther at Guitar Parts and More. I wanted a black nut with the factory look, so Buffalo was it.

Using the Buffalo horn is just like working with cow bone. (Moooooooo).

Cut it to size.

Note the small notch on the bottom to clear the truss rods.

Lay out the string pairs as described above, and shape the top.

In this shot, I still need to trim the edges, but the nut is close to being ready.

Then polish as usual. The white marks are polishing compound, I got most of it out later.

Here's the Buffalo bone nut polished and ready to install. I started with 600 grit paper, went up to 12000, then used a swirl remover compound fo the final shine.

Looks good I think.

For comparison, here's the stock nut. Note especially the G, B and E pairs are spaced. We know from the measurements that there is some progressive spacing, but to the naked eye, the pairs look like the spacing is almost the same.

And the E pairs are further in from the fretboard edge than the new nut below.
And this is the spacing on the new nut.

The E pairs are moved out, which opened up more space for the other strings.. The D, G, B, and E pairs are noticeably closer together.

You'll see where (I admit it) I could have gotten the A (especially), D and G pairs even closer together. I didn't have a good idea of how well it would work until it was strung to pitch.

Next time, I will be able to improve on this. But as Toy Making Dad would say, this was a proof of concept.

So the real question is how does it play?

It's remarkable. Just a few thousandths here and there makes a huge difference. In an open C chord, for example, the G and D strings don't get muted by the 2nd finger as they did before. It's really nice.

Now I want to try making another one and refine this a bit more...but clearly this solves the string spacing problem!


Custom Nut for Rickenbacker 12-String, Pt. 1

A while back I wrote about my Mapleglo Rickenbacker 360/12C63 guitar. At that time I adjusted the truss rods and put a 12-saddle bridge on it.

It played ok, but there was still too much relief in the neck which made playing above the 5th fret or so an adventure.

Not to mention that it suffered from the infamous 'strings-too-close-together' syndrome common to all thin hollowbody Ric 12s. Meaning, my fingers were damping adjacent string pairs inadvertently due to the stock string spacing.

After reading a lot of stuff on the interwebs, I decided to take a shot at making a new nut with revised spacing. And also get that nagging relief out of the neck.

One small mod I made right off the bat was to round off the edge of the name plate/truss rod cover. I love the look of this thing to death, but the relatively sharp edge is a recipe for sawing strings up when they're being tuned.

There are a few points (I think five...) where strings pass right over the edge of the cover. The pencil in the picture above shows one of these strings - see how the octave D string contacts the cover as it passes over it.

There's an easy fix and no one will even notice it.

With a fine file, I just rounded that square edge into more of a nice curve.

After the filing, I sanded it a bit with 600 grit paper.

It might be hard to see in this shot, but you should be able to see the new top edge. Looks dead stock from the top, but the edge is there.

Really easy to do and makes your Ric 'modded!'

It also makes it a bit easier to slide the truss rod cover under the strings when you put it back on. You still can't do it with the strings tuned to pitch, but you'll experience less string 'poink' and 'boink' when you slide it on.  Since I have muy expensivo Thomastik-Infeld strings on this puppy, I don't want to snag and break them.

Ok, let the real fun begin.

At some point, I had procured a replacement nut from the Rickenbacker factory (in the front in this picture) thinking that perhaps I could fill the existing slots and cut a new one from that.

However, after some thought, I decided to dispense with that idea and take the opportunity to plunk down $12 (!) for a gee-whiz 'modern' Tusq nut. It's in the rear in the picture. You will notice that it's black, just like a stock Ric nut. Now, there is no rule against using a white nut on a Ric (well, maybe there is...more on that later), I like the look of the black, especially on a maple guitar, so Tusq it was.

Now, most luthiers, including my man Dan Erlewine, will tell you that bone, hands-down, is the best material for nuts and saddles. I've made a lot of saddles and nuts out of bone, and I agree.  It's easy to work, yet it's dense, and it is far superior than plastic for a fine instrument. (Even a cheap instrument will benefit). Ivory is even better, but other than fossil walrus ivory, it's illegal, and for good reason. And the fossil ivory costs big money.

But the Graphtech people, who make Tusq products, say this about their material:
Bone and Ivory nuts and saddles have one inherent problem - they're made from organic materials, and therefore have inconsistent soft or dead spots because of their natural grain.  TUSQ nuts, saddles and bridge pins are precision engineered under high pressure and heat, specifically to govern which frequencies are transferred to your guitar top (tone), and which frequencies remain in the strings (sustain).
I am willing to give it a shot. I'm thinking, if it works well, I'll make some for my guitars with vibratos.

Before we get too much further, I want to show the stock string spacing on the guitar. You can see it on the left.

Note that to the naked eye, the spacing looks virtually the same between each of the string pairs - that is, the spacing seems to be the same between the two Es, the As, etc.

There is some difference in the spacing on the individual pairs; I'll provide more detail in the next post.

Clearly there is an issue with not enough spacing between adjacent  pairs (the B, G and D especially). Studying the stock spacing, and reading about it on the interwebs got me to thinking that the string pairs could be spaced closer together.

By putting each pair closer together, it would create more space between one string pair and the next. We're looking at small amounts here, but those small amounts should make a substantial improvement.

So I'm going to lay out the new nut. But first, we'll get the old nut off the guitar.  Using a wood block and with a tap from a hammer takes the nut right off.

Next we'll calculate the new string spacing and lay it out on the Tusq nut.


Triplett 3434a Sweep Signal Generator Restoration - Pt. 3

Only have a few more things to do on the Triplett 3434a before it's all done.

I put a modern 3-prong grounded AC cord on. The old 2 prong cord was a bit wonky - it would cut out when it was wiggled (!), and a piece of test gear like this really should have a proper mains ground anyway.

The AC line comes into a shielded can inside the chassis. There are 2 coils on the line as well as 2 safety capacitors to cut interference. The can unbolts from the chassis easily.

There are 3 screws - you can see one that I partially undid - that hold the can onto the base. You can't remove the top of the can without removing the whole thing from the chassis. There is enough slack in the wiring that you don't have to disconnect anything though.

Here are the innards I mentioned. There are terminal tabs that the AC cord is soldered to. Just unsolder them and the new cord can be soldered on.

Note also the rubber grommet on the can - everywhere wire passes through a hole in the chassis, there is a grommet to prevent a wire contacting the chassis and potentially causing a short. Very nice.

Here's the new cord in place.

The black, hot side, goes to the side of the circuit with the AC switch and fuse. The white, neutral, goes to the other side of the power transformer.

And the green, ground, comes out of the can to go to ground.

You can see I put a ring terminal on the ground lead.

The can back in place.

The green arrow points to where the new AC ground lead goes. It's connected to the main chassis ground - worked out perfectly.

There's a connector on the outside of the chassis to ground the whole generator. So the AC ground goes to that point.

The cabinet was a bit dingy - I cleaned it up with Simple Green.

There is some rust and corrosion on the handle bracket on the top, and the leather handle is looking a bit sad.

So I cleaned them up with a rust remover and leather cleaner and treatment. I used both of those Passier products on my SAAB 900 convertible's interior and I like them a lot. They're actually intended for horse bridles, but, hey, leather is leather, right?

The Lederbalsam is a cream that you work into the leather. It's nice because you can let it sit as long as you'd like while the leather soaks it up, unlike a liquid which might evaporate.

Got the rust off the brackets. Most of the plating is gone, but the brackets at least look shiny.

And it's hard to tell from this picture, but the leather looks much better, and it's now soft and pliable.

You can also see that even though I masked off the cabinet, I still managed to get some of the cleaning stuff on the metal. It came off easily.

I had a few spots of ground-in dirt on the cool embossed front panel. I hit the spots with some Simple Green on an old toothbrush, then got the remaining dirt out with toothpicks.

A little effort yields big results. Well, maybe medium-sized results.

The finished generator. The glass is so shiny now that it reflected me with my trusty Canon camera!


Triplett 3434a Sweep Signal Generator Restoration - Pt. 2

I'm going to recap the Triplett signal generator. The filter caps are in one of the Mallory cans typical of this period (1960s I believe).

So I need to remove the large blobs of solder that are on the chassis and the can's mounting tabs.

For that job, I use my 175-watt Weller soldering iron, aka 'Big Bertha.' And some soldering wick.

I do clean and tin the iron for every use, but it still gets dull in between uses. So I clean it with a soldering cleaning block and tin it.

Over the years, I've used a variety of tools to cut open filter cans - hacksaw blades, kitchen knives - but now I think I've found the best tool for the job.

This is a flush-cut saw I got from Stew-Mac. It's designed for cutting braces, dowels and other similar things on guitars. It has a very thin kerf (I measured it at .012 in or .30 mm), which is ideal.

Mine is an older model - they now have a newer one which is probably even better.

Here I am cutting the can.

The saw is very sharp and made quick work of the thin aluminum can.

I forget how easily these things dent.

I've written before about this process, so this time I'm just showing the highlights. You can search to find more.

But it really isn't rocket surgery.

Usually the innards of the can are dried up and just slide right out.

But this one was still together and took more work. I wound up using a screw extractor and it came right out.

Here's the extractor. This one is 1/2 inch (about 12 mm). The threads are left-hand.

Drill a pilot hole into your broken fastener, then drive this into it and turn. Since the threads are left-hand, it will turn the fastener (or can capacitor innards...) to the left as you drive it in.

If you work on old British cars, you will need this eventually.

You can see how the innards came right out.

It's a capacitor on a stick!

With the can empty, we can put modern caps on the base, and run wires down through holes in the base. Then solder to the appropriate terminals.

A lot of people won't do this. I like it because it's easy, sort of fun and keeps the original look from the outside. In a lot of gear, there just isn't enough room to put discrete caps under the chassis. And even if you can, it generally winds up looking sloppy.

Sure, you can buy new production cans. But if you keep a decent stock of electrolytic caps on hand as I do, it's easy to take 15 minutes to get the can out, open it and put new caps in. Better than ordering an expensive can and waiting a week for it to show up, too.

Just my opinion. Once you do one, it's like eating peanuts. You can't stop.

Then we use epoxy and put the can back together.

You can also paint over the seam if you want to make it look more original. I did not, but I should have. Doh.

Here's the can reinstalled.

Nice solder blobs, huh?

Bertha does great, but boy, when you are holding that iron upright like I was here with your hand and head over it, it gets really hot!

I put a note on it to indicate it was serviced.

Aside from the filter cap, there are only 4 other caps to replace. They're all in the audio frequency circuit - it generates a fixed 600 Hz signal.

Here are 3 of them - the new caps are yellow modern poly. They replaced old paper foil caps.

The fourth is an electrolytic on a terminal strip.

I also straightened out that dent where the sweep output jack is.

Turns out the aluminum panel is so soft that I could bend it by putting a connector on the jack and just moving it sideways.

The dent probably happened the same way in reverse - a cable was plugged in and took a hit and the panel got bent.

I still needed a few taps with a hammer to get the panel perfectly aligned.

Next I'll put a proper 3-prong grounded AC cord on.