Guitar Neck Repairs: Splines

Headstock repairs are nothing new in these parts. If you pop by the Haze blog from time to time, you'll probably have seen more than a couple over the last few years. We've also talked about the need to reinforce some broken headstocks with a 'backstrap' (a piece of wood that overlays the repair to add strength).

I like backstraps. They're an effective and discreet way to strengthen a neck repair. They can take a bit of time and effort to do properly, though, and splines are not the only game in town. There are times when an alternative is preferred. 

Splines are the prime candidates.

Spline Headstock Reinforcement

A spline is a slat of wood that's inlaid into a channel cut in the neck.

Like this:

Reinforcing a broken guitar neck repair with splines.

The idea is that the channel runs for a distance either side of the repaired crack. A slot is routed and the spline glued in. The newly inserted 'good' wood of the spline ties together the good wood on both sides of the crack.

As you might expect, the splines are carved down to match the neck and the finish touched up. Splines are not quite so inconspicuous as a well-executed overlay but they are an excellent way to bolster a neck repair that needs some reinforcement. 

And, in the right circumstances, you can even get inventive in your splines


Guitar Hardware School: Nuts III - Fitting

If you've managed to get through the last couple of Hardware Schools on Nut Materials, well done. Hope your stamina holds out to take a look at fitting a nut. 

Materials are only part of the picture. For a nut to do a good job, it must be properly fitted and well slotted.

A Good Tight Nut Fit

Proper fitting is really important. Apart from the aesthetics and feel, a nut must make good, solid contact with the neck and fingerboard if it's to work well. 

You don't want the nut to impede a string's vibration and a less-than-solid contact between nut and neck is a recipe for sucking out string energy. In the same way that soft plastic nuts can soak up vibration, a badly fitted nut can also kill your tone. 

You're looking for a solid, even contact along the bottom of the nut and along the front surface (that butts against the fingerboard). In an ideal world, we don't want to see shims under nuts and any softer shims are definitely out. It's worth mentioning that I occasionally use bone shims. While the first choice would be to replace the nut, a bone shim can do a decent job if that's not an option. 

Slotting guitar nut

Nut slots

Lots to consider with slotting:

Nut Slots: Spacing

Each string slot in a nut must first be properly spaced. Generally, this spacing isn't the same across the fingerboard but increases very slightly as it moves from 1st string to the bottom—as the strings' get thicker, the spacing gets bigger. We're not talking about very much of a difference but you'd be surprised at how unpleasant things feel if the spacing is incorrect. 

Nut Slots: Height

After spacing, the next job is string height. Each string-slot in the nut must be correctly cut to give the optimal setting for that string. If the slot is too low, the string will probably buzz off the first fret when it's played. If the slot is too high, playability will suffer, as will intonation. A too-high slot means you'll need to stretch the string farther when fretting, especially in the lower positions. This can definitely kick out your intonation and make for nastiness. 

Nut Slots: Size

Finally, the string slots need to be the right size for each string. I have a lot of gauged nut-files. Each is a slightly different size. I can pick the right file for each string-slot, matching it to the string that it will hold. 

Too big a slot—say a .042" slot holding a .016" string—will allow a string some sideways movement which isn't ideal. Worse, however, is too small a slot. This can bind and pinch the string, often causing tuning issues. If you've ever had a string 'ping' as you tuned it, you might have too tight a slot (or the string has begun to wear the slot, basically cutting its only slot and catching in that). 

Nut slots are too deep - excess above the strings should be removed

Nut Slots: Depth

You might think this is the same thing as height but there's an extra component to think about. After the slots are cut, the excess nut material above the slots should be removed. While there's an argument that this is (at least partly) for reasons of tone, in my view, it's mostly because it's ugly. Big deep slots and a quarter-inch of nut above the strings just looks a bit rubbish. 

Ideally, your wound strings should have about half to two-thirds of their diameter in their slots and the unwound strings should sit just below the surface. 

Pre-Cut and Pre-Slotted Nuts

For the most part, any nut I make (whether bone or one of the alternatives) is cut from a blank. This is just a hunk of that material that I cut to size and shape before slotting. This allows me to get the best fit and look for my nuts. 

However, many nuts are available as pre-cut and pre-slotted pieces. Personally, I don't really like these but I have the luxury of having the correct tools and a bit of experience. I realise that pre-cut nuts from Tusq, or similar material, can still be an excellent home-fit upgrade from a guitar with a cheapie plastic nut. 

If you're doing one yourself, remember that it's not usually a case of just dropping it in. They'll usually require a little sanding and shaping to fit properly. In the absence of gauged nut-files, height adjustment on these is done by removing material from the bottom. This can make for an awkward balancing act to get things right across the bass and treble sides of your neck so go slooooooooow. It's a pain, but do a tiny bit at a time and keep putting the nut back on and retuning (always check when tuned to pitch) to see where your string height is. 

If you've found this useful, you can check out others in the same series of Guitar Hardware School. Feel free to share these on and shout up in the comments if you've questions. 

I am Legend

So, by now, you should have had a look at the build photos from the Vee-Twin. I'm working with Radio Nova again this year and they'll be giving away one of these beauties during the last week of October (or Rocktober, if you prefer).

The keen-eyed will have spotted that there are two Vee-Twins on the go in these photos. Well, similar to Victor Kiam who liked a razor so much, he bought the company, Nova are getting a handsome Vee-Twin all to themselves.

Nova get one but the other guitar could be all yours if you tune in at 100FM over the next few weeks—check it out. 

In the meantime, have a listen to this. Personally, I have it on repeat all through the day.  

Haze Guitars Vee-Twin

Weak Neck Fail

repair guitar neck

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.

guitar neck tenon break
neck joint failure repair

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.

fix guitar neck joint
repair guitar tenon joint

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.

Bespoke Bridge

IMG 2959

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.

custom acoustic guitar bridge
acoustic guitar bridge fix

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.

glue acoustic guitar bridge
acoustic guitar custom bridge

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.

Les Paul Neck Removal and Repair

les paul broken neck heel

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.

les paul heel repair frets
les paul neck removal

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.

gibson neck removal
steaming off gibson neck

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…

les paul neck tenon
les paul neck joint repair

…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.

gibson guitar neck tenon repair
les paul neck joint fix

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.

gibson neck tenon repair
les paul repair touch-up

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.

Christmas Opening 2012

haze guitars instrument repair dublin

It seems like my internal organs have barely recovered from last year and Christmas is here again. Ho ho ho.

While it would probably be cheaper just to pay someone to kick me repeatedly in the liver for a week, it is traditional to take a little time off to ruin my health the old-fashoined, Irish, way.

With that in mind, Haze Guitars will be closed for the Christmas period. Other than a couple of collections I've already arranged, Haze will be closed from 23rd of December until the 2nd of January.

I will be answering the occasional email as family/turkey sandwiches/hangovers allow so feel free to drop me a line. 

Come January, I'll continue to follow tradition by holding the Great And Marvellous, Definitely Going To Kill Me This Year, January Setup Sale. More info on this—and some other exciting news for January—over the next week.

As I always do at this time of year, I want to say an incredibly massive thank you to everybody who's trusted me with their instruments over the last year. I know what it means to hand over your precious and I genuinely appreciate your trust. I hope I was able to help.

Thanks for everything this year, and have a great Christmas.

Extended Saddles and the Curse of a Good Ear

guitar saddle extended

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.

Things Are Afoot: New Model Teasing

I've been posting photos on Facebook and Twitter with the title, Things Are Afoot. I'm teasing…

I've a brand new guitar model preparing for release. I'll be announcing things soon but for now, follow me on Facebook or Twitter where I'll continue building you up into a frenzy of slavering anticipation.


Haze Bassmaster and Radio Nova

Haze Bassmaster 6

Haze Bassmaster 6

The time has come. Tomorrow morning (Monday 16th July), I'll be down with the lovely people in Radio Nova to present the Haze Bassmaster 6 to its new owner, Greg. Greg won Nova's Rocktober competition and his prize was a custom, hand-built instrument from Haze Guitars. After some discussions, the Haze Bassmaster 6 (with a few tweaks) was decided upon.

Thirty inches and six strings. The Bassmaster is a wonderful, quirky, beast with a tone that'll get you noticed. This one looks great with a lovely ash body peeking through that burst. Nice. You can check out the build process for the Nova Bassmaster if you like or you can read a little more about the Haze Bassmaster 6.

More images to come but do tune in to Pat Courtney on Nova tomorrow morning (100FM) and you might get to hear a bit more. Hurrah!