Have you boiled your pickups?

Effectively, that’s what I’m doing here. These Jag pickups are taking a bath in a pot of hot wax.

When we talked about pickups a little while back, we discussed the fact that they were, for all intents and purposes, a big coil of wire and some magnets. Sometimes, the windings of that coil can move around a tiny bit (sometimes vibrating in sympathy with the note being played or just as you jump around the stage). This movement can be ‘picked up’ and added to the amplified sound which can result in nasty feedback. Pickups with this issue are often referred to as being microphonic.

Soaking in hot wax—called potting the pickup—allows the liquid wax to seep through the gaps between the windings and the other hardware (base-plates and so on). Once the wax cools, it solidifies in these gaps and helps prevent that movement. It’s important that the pickups are soaked for a while. When they warm to the same temperature as the wax, that ensures good penetration deep within the coils. You’ll notice a bubble in the photo—these continue to pop out slowly as the wax penetrates.

Wax tends to be the most common potting material as it’s easy to apply and makes it possible to disassemble the pickup in the future if the need arises. Lacquer and even epoxy have been used from time to time but neither penetrates as well as wax (they’re too thick) and they cure into impenetrable, hard, pickup-shaped lumps. Forget about disassembling one of these.

There are a couple of things worth mentioning on this subject:

Firstly, many of the most sought-after tones come from un-potted pickups. Some tones/styles can benefit from a very slight microphonic edge.

Secondly, it’s not necessarily a panacea. Potting can help reduce microphonic feedback but there can be many other contributors to feedback. If you’ve a problem, it’s worth considering everything in your signal chain.

This is a particularly handsome Heritage 535. It would be even more handsome if it were in one piece instead of two, though.

The neck’s come off and a little bit of investigation shows that it never stood a chance. This neck joint was weak from the start.

These joints are referred to as ‘mortice and tenon’ joints. In this case, the tenon (the bit at the end of the neck) was too small for the mortice (the ‘pocket’ in the body). As well as having a relatively large shim on one side, the tenon didn’t make contact with the bottom of the pocket. There’s an gap of a couple of millimetres between the two.

You can see the circled bits in the image. On the left is a chunk of mahogany from the tenon that’s split off and the glue line is visible on the right. You can see the gap.

That gap means no glue joint there. Only the sides are glued (well, those and the ‘face’ of the joint but that’s not providing a lot of strength).

This is a weak neck joint that was much more prone to fail that it ought to have been.

Rather than just gluing it back together, I’m going to build up the tenon to get this joint to where it should have been from the factory.

First off, that little chunk of mahogany that’s still glued to the side of the neck pocket has to be removed and glued back to the neck tenon. Once that’s done, I nab a new bit of mahogany and thickness it so that it will fill the gap.

In the right photo, you can see I’ve glued this on and cut it to match the shape of the existing tenon. The thickness of the added wood gives you an indication of how much of a gap there was.

I removed the old glue from both parts and re-glued the neck to the body. Because the break was quite clean, only a little touch-up work was required to get the guitar looking its best.

This repair looks good and, importantly, has actually resulted in a better, more sound, neck joint than when it left the factory.

OK, I’m going to have to be careful with this one as it would be easy to get bogged down in the minutiae of pickup polarities and phasing issues and, before anybody knew it, I’d have written a book to rival Britannica.

At a very, very high level, then, a humbucking pickup consists of two coils of wire (wrapped on plastic bobbins), a bar magnet and some ‘pole-pieces’. For the purposes of this discussion we can just concentrate on the two coils of wire and the magnet.

These two coils sit side by side (as you see in the photo). The magnet is a length of bar that sits underneath, basically in the middle. The bar-magnet has one side (not end) as a north pole and the other as a south pole. In this way, each of the wire coils is effectively magnetised with opposite polarites.

When these opposite-polarity coils are connected so they are electrically out-of-phase, (effectively one coil winds clockwise and the other anti-clockwise), the result is that much of the nasty interference that can be picked up is cancelled out while the actual string’s vibration isn’t. It’s a hum-cancelling (or bucking) pickup. Brilliant. Hurrah for Seth Lover and, the cruelly forgotten, Ray Butts.

Why am I telling you all of this? Mainly to seem impressive and knowledgable. I may grow my beard out, stroking it all the time, until it’s bushy and scholarly. Also, I’m telling you so the rest of this makes a bit of sense.

When two pickups are used in the same guitar, magnetic polarity and their coil-wrap directions can interact to cause different effects. There are other variables too but that’s a topic for another long, rambling post.

Generally, there’s an ‘accepted’ way to install pickups (but rules are made to be broken—experiment and maybe you’ll find a Peter Green sound or similar) and, mostly, you don’t need to worry about the polarity of each coil on your humbucker.

But sometimes you do. It’s difficult to give you a list of the times this is necessary but, for example, some guitars (some PRS and Ibanez models spring to mind) implement switching options that offer various coil-tap options and this can help keep mix positions hum-cancelling. To accommodate these options, sometimes one of the pickups has its magnetic polarity ‘flipped’. If you’re dropping in some new pickups to these guitars, it can sometimes be necessary to consider magnetic polarity to prevent things sounding weird or unpleasant.

Then, we flip the magnet ourselves. Here’s how to do it if you need to*.

Unwinding the wrapping around the coils reveals the hook-up wires. If you touch these, the world will end in a massive fireball of guitary doom. Don’t poke them. Leave them alone.

On the bottom of the pickup, the baseplate will have some screws holding the bobbins to it. Loosen these but just a little—you don’t want to bobbins to fall off.

Now, carefully, give the bar magnet a shove (away from the hook-up wires if they’re in the way). It will emerge like the photo on the right. When it’s out, don’t look away—flip it before you loose track (it can be a good idea to mark it with a fine permanent marker so you don’t go astray if you like).

When flipping, remember it’s NOT end to end. It flips in the ‘short’ direction. See the arrow in the photo? Flip it that way, 180º (one half rotation).

Reassemble and proceed with your wiring, content in the knowledge that your pickup’s magnetic polarity has been flipped. What was the north coil is now south and vice versa.

Now start growing your beard.

*A word of caution here. If you decide to try this yourself, be massively careful. Pickup coil wire is incredibly thin and delicate and will break if you look at it for too long. It’s that delicate. Also, if the whole pickup falls apart into many different pieces, it won’t be fun to put back together. This is an At Your Own Risk sort of job.

Let’s be honest, that’s not an attractive bridge. It’s seen a lot of action over the years and it’s cracked and, somewhere in the distant past, it’s had some gunky filler splodged in to try extend its life.

And it’s actually a slightly odd bridge. Although it has six holes for bridge pins, you can see along the back there are some filled holes as if this bridge were once strung from the top. There are also two little pearl dots which are usually present to hide small bolts (as they do in this case). These bolts are generally used on bridges that string from the top. But, then, why the bridge-pin holes?

It seems likely that the manufacturer repurposed this bridge from another model, filled the string holes and installed with bolts as normal. Fair enough.

This is all an aside anyway. On to the real work.

The owner wants this sorted but I wasn’t able to source an off-the-shelf replacement. This means custom-malking a replacement.

Getting these things off is a pain—as well as the two little bolts under the pearl, this manufacturer epoxies the bridge in position. I may have used swear words.

Once off, though, I grab a nice piece of rosewood and thickness it to about the right height. I carefully measure and mark off the important dimensions, particularly the pin holes and the bolt holes—if these are misaligned or misplaced, the bridge has to go in the bin.

Some careful drilling and we’re ready to shape the bridge. In this case, it’s a (relatively) easy job as the original doesn’t have a lot of sharp edges to curves that need to be replicated. It’s easier to replicate those sweeping lines.

Re-attaching the bridge, in this case, means epoxy again. There’s a major risk of the bridge sliding about as it’s clamped so some very careful preparation was necessary to ensure this didn’t happen. Pin-holes and the bolts came in useful in this.

And, you can see the end result in the last image. As it’s a nicer piece of rosewood, I think the new bridge actually looks better than the original but, that aside, it’s certainly more sound.

Yikes.

If you’ve been reading my stuff for a while, you’ve probably spotted a few different examples of neck breaks. Most of these have been up at the headstock end as that’s the more likely place for a break.

It can happen down the other end too, though. This Les Paul took a tumble and broke in a nasty way. The exterior damage is obvious but it’s pretty certain that crack extends into the neck tenon too (the tenon’s the bit that gets glued into the neck pocket in the body).

This neck needs to come out to be properly repaired.

It’s not too often that I need to remove a Les Paul neck, which is lucky as it’s a relatively involved job. With a strong cup of tea to steel myself, I set to work.

First up, a few frets need to come out. To remove this neck, I need to soak and steam the glue out and that means getting access to the internals of the neck joint. I do this by drilling small ‘access’ holes. These are drilled in the fret slots. When it’s all done, I’ll fill the holes with rosewood plugs and re-cut the slots. All of this is hidden by the refitted frets.

Your eagle-eyes will have noticed a little dot on each (numbered) fret. These frets will be refitted and the dot tells me which is the bass end.

Keeping fingers crossed, I take a look under the neck pickup, hoping for a long tenon. No luck. If I could have seen the end of the tenon, I’d know exactly what size it was so I could position my holes to accurately access the sides of the neck joint  (if it’s not clear what I mean here, a photo later on might clarify things).

Since all of this tenon is hidden, I have to measure out the usual Gibson size and position for this guitar and hope that it’s built properly to spec.

In the photo, above on the right, you can see the pencil marks I’ve used to plot out the tenon and the holes I’ve drilled to get access to the joint.

This one’s a bit weird-looking, I’ll admit.

In the left image, I’m using a syringe to insert boiling water into the holes I’ve drilled. I give it a few seconds and then suck it back up again. What comes out is cooler water with some manky-looking dissolved glue. I repeat this process a lot over the course of a couple of days. A Les Paul neck joint is a hell of a strong joint and doing this gives me a little bit of a head start before I hit it with the steam.

Which is what’s happening on the right. That nozzle lets me get piping hot steam deep into the joint. The heat and moisture helps to dissolve more glue and, after some time and work, the glue eventually lets go…

…Leaving most of the bloody tenon still in the pocket. D’oh!

The heel crack extended into the tenon as we thought. Now I have to keep working to get this piece out with pretty much no leverage.

More tea required, I think.

Some steamy swearing later and it’s out. Now, in the side of that neck tenon, you can see the tracks of those holes I drilled earlier. We were right on the money with the positions too—nice.

And here’s the jigsaw we need to get back together. You’ll notice a small shim in the neck pocket. This was installed at the factory (it’s not uncommon) and I’ll reuse it for this repair.

All of the old glue is cleaned from the mortice and the tenon and then, the two bits of neck are glued back together. Again, the tracks of those access holes are clear in the photo on the right.

Once it’s sound again, the neck is reattached to the body. Those frets are reinstalled and all the frets are levelled to ensure clean playability.

Then, it’s just some touch-up to hide the evidence. As the rear and neck of this Les Paul are black, the opaque colour easily disguises the repair.

It took a bit of thought, a lot of work and twelve buckets of tea but this job’s a good ‘un.

I rambled on about acoustic guitar intonation a while ago and mentioned that sometimes, the proper intonation point for a particular string falls somewhere fore or aft of the actual saddle.

In some cases, all of the instrument’s other strings do likewise and this can be an indication that the saddle slot may be in the wrong place. Often, however, it’s just one outlier. One lonely string, steadfastly blazing its own out-of-tune trail. An intonation maverick, if you will.

It’s not always a big deal. Perhaps it’s just a little out or, perhaps your ear/brain isn’t particularly bothered by it. However, if you’re one of those cursed with tuning-sensitive ears or if your poor, perfectly-pitched brain screams in discordant agony when you play certain chords or intervals, you might want to consider drastic action like this.

Well, it’s not terribly drastic, really. I’ve made a new saddle for this tenor guitar from a bone blank and all strings except the third intonated quite happily. The delinquent string wanted to intonate miles away from the saddle.

So I extended the saddle.

There are a couple of options for this but the most straightforward is an additional piece of bone that’s been glued to the rest of the saddle. It’s half the height of the saddle itself—it lacks a ‘bottom’ half and it actually rests on top of the wooden bridge so it’s completely reversible (just pop a new saddle in). It gives me the additional scope needed to shift this string’s intonation point forward.

Looks odd but sounds much better.

Time to break up all this Burlesque talk with something a little different.

What’s going on here, then?

Intonation. It’s a bug-bear for some. We could talk about equal temperament concerns and mathematical subdivisions of scale-length and whatnot, but it would get dull quickly. Suffice it to say, tuning on any fretted instrument is always a little bit of a compromise.

In order to try get the damn thing to sound as closely in tune as possible, we ‘intonate’ each string to compensate its length so it sounds right when fretted. On most electric guitars, we do this by adjusting the string’s saddle—moving it backwards or forwards to slightly lengthen or shorten the string’s sounding length. Easy-peasy (unless it’s a Floyd Rose-type bridge in which case it’s more annoying than being repeatedly kicked in the shin by a crying child in a restaurant).

Acoustic guitars offer a bit more of a challenge than most electrics though.

An acoustic guitar generally has a fixed saddle (of bone or whatever). The fact that the saddle is installed at a slight angle (increasing string length from 1st to 6th) string is a nod towards some string compensation. The pre-shaped, compensated saddles that many guitars have these days is another step in the right direction.

For most people (and most guitars and strings) these get close enough that tuning issues aren’t glaringly awful.

Sometimes, and for some people (depending on playing style and the curse of having a good ear), it’s not enough.

Intonation depends on precisely seventeen million variables. Well, give or take—there are a lot of factors that all interact to determine the best setting. Tweaking setup and string choice can help if there are problems but sometimes that’s not an option or isn’t sufficient.

What’s going on in the images above is that I’ve used little chunks of rosewood to individually intonate each string on this acoustic guitar. The saddle has been removed and the rosewood is acting like an individual saddle for each string. I poke it back and forward to find where each string properly intonates.

StewMac actually offers a doohickey that does this without fiddling with bits of wood. I’ve been threatening to get one for a while but I’m forgetful and tight.

Popping a piece of cellophane over the bridge lets me mark the location of each intonation point and the actual saddle location itself. This gives me an indication of where each string should sit on the saddle to sound best. It’s easy to transfer this to a new saddle blank.

This guitar, its setup and strings, actually indicates a complication: As you can see in the image in the right, some of the optimum intonation points sit outside the actual saddle.

This happens sometimes. On an older guitar, it’s not unusual to have a saddle actually misplaced. This can necessitate filling the slot and actually re-routing it in a new position. That doesn’t tend to happen so much these days but, depending on other factors, it’s possible that one or more intonation points might be in front of, or behind, the saddle.  Of course, making a much wider saddle is an option but that adds expense and entails modifying the bridge to accommodate that wider saddle.

The other option is compromise (we’re back to that word again). In this case, carving a new saddle with intonation points as close as possible to those measured will improve things considerably. Four of six strings will be pretty much perfect and the remaining two will be a lot closer to perfect than they originally were. Overall, it sounds much more in tune than it did without the need to irreversibly modify the bridge to accommodate a wide saddle.

So, we end up with a slightly odd looking saddle that sounds a lot better and the original is safe in the case in case it’s ever needed. Not too shabby.

It’s worth remembering that this is probably overkill for the majority of people. Most guitars and guitarists are generally ok with the regular or pre-compensated saddle. Failing that, a good setup or a change of string-gauge will probably get you close enough that you’ll be happy. If you’re still hearing problems though, a custom-compensated saddle might be an option.

Haze Guitars offers a professional guitar and bass repair, upgrade and restoration service for Dublin and the east coast of Ireland.

I have been designing, building, hot-rodding, modifying and repairing guitars for years. I’ve made many instruments in many styles and have been lucky enough to work on countless new and vintage instruments in order to repair, set-up or restore them.

I can offer a full instrument repair, setup and upgrade service for any manufacturer’s guitars or basses. If you’ve problem with your guitar, bass, or even other stringed instruments, just drop me a line – I’ll take a look and do my best to help you out.

I also write repair and tutorial articles for the online guitar news website, Guitarless. Be sure to check them out.

If you’ve had a Telecaster for any length of time, there’s a reasonable chance you’ve experienced Wobbly Jack Syndrome. It’s an annoying condition that afflicts Teles from time to time.

You know it… That little recessed metal dish or cup that holds the output jack starts to get a little loose. After a while, it’s very loose and—sometimes—even causes nasty signal cracks and output loss.

Inside the hole in the side of the guitar, the output jack is mounted through a metal ‘retainer clip’ and the metal cup. The retainer clip (photo on the right below) should hold it all tightly in the wall of the hole but sometimes works its way loose.

The clip works on a really simple principle: it goes into the hole with its sides bent (as shown above) and is forced to straighten. This causes the sides to dig into the hole-wall and holds it all in place.

Easy. And it’s an easy fix if you have the right tool. If you don’t—despite the easy principle—it’s almost impossible to do properly.

And that ugly looking hunk of metal in the photo on the left is the right tool. Leo Fender may have given it a proper name but, for me, it’s just the Tele Jack Clip Installation Thing. It makes it easy to remove an existing clip or to properly install a new one. Without it, you end up hacking aimlessly and hoping for the best.

If you’re fed up with wobbly Tele jacks, a device called an Electrosocket can be screwed in to replace the, rather fiddly, clip and cup arrangement. It’s not something you’d really do with a nice vintage Tele, though. In that case, occasional wobbly jacks are just part of the magic.

It’s certainly been mentioned a few times around here that the strings on your guitar exert quite a bit of tension on the neck. Enough, usually, to pull the neck into a ‘bow’ shape (with the middle being farthest from the strings). Our trusty truss-rod can generally be called on to counteract that tension and to control the bow or even straighten the neck completely against the string pull.

Sometimes, however, we get what’s referred to as ‘back-bow’. With a back-bowed neck, that bow shape is effectively reversed and the middle has ended up closest to the strings. This means that a note fretted in the lower end of the neck can’t sound clearly as it hits off the ‘uphill’ frets all the way to the middle of the bow.

There are dual-action truss-rods available and these are able to correct for back-bow as well as, the more normal, forward bow. They’re becoming more common but lots of guitars still have the usual single-action rods that can only correct forward bow to counteract string tension. As this is what it needs to do in 99 out of 100 cases, that’s generally fine.

But sometimes it’s not.

Setting up this guitar, I found it was back-bowed beyond the point where string-tension would have corrected it. Open notes and those as far as the eight fret or so all choked or buzzed. Even with the truss-rod slackened off completely, the neck wouldn’t pull straight or into relief (a very slight bow).

There are a number of things that could be done to try to address this, some of them relatively involved jobs. Before getting into those discussions regarding what isn’t really a super-expensive guitar, I had a punt at a quick-fix. This doesn’t always work and isn’t always suitable but it’s certainly worth a go in this case.

In the first photo, I’ve got my heating blanket sitting on the neck, weighted down by a heavy fret-leveller. I don’t want to go nuts with the heat here. Too much will just cause hassle in this case but I’m applying sufficient heat to slowly heat the glue holding the fingerboard to the neck. I don’t want it to completely let go; just to soften slightly.

When I think it’s where I need it to be, I clamp the neck into a bit of a forward bow and leave it to cool. If things go to plan, the glue will re-harden and help the neck to hold some of the shape I’ve forced it into.

And, luckily, things went to plan. Unstrung, the neck now has just the slightest of back-bows and, under string-tension, that pulls into a little relief—enough to get it playing nicely again.

Incidentally, a workplace safety tip: Even if you are fully aware that this procedure will leave your steel fret-leveller in a very hot condition and, even if you wear heavy gloves to move it, you shouldn’t put it over to the side of your workbench, right where your elbow will touch it when you’re checking clamping pressure. That would be stupid.