Refretting an unusual Les Paul

This was an interesting and unusual refret of a 1971 Gibson Les Paul Recording, belonging to Meshuggah soundman Thomas Hedblom. This was Les’ own preferred model and has some unusual features for a Les Paul – most notably low / high impedance switching. This guitar has seen many years of hard playing, and needed some good ‘ol TLC to bring it back to optimum playability. The action was stiff, neck was bowed considerably, the bridge studs were shot and basically couldn’t be lowered normally, and the frets were extremely worn.

After the initial inspection, the guitar is placed onto the neck jig to begin preparations for a refret.

While setting up the neck jig, one of the things that was immediately apparent was a slight counter-clockwise twist. This guitar has a previously repaired headstock break, which may have also contributed to this, but it can happen in a few different ways. How or if the playability is affected itself will be apparent very shortly, and dealt with if necessary.

The key/purpose of the neck jig is to allow fretwork to be executed by simulating the neck being perfectly adjusted in the playing position with the strings off and then laid horizontally for the work. As gravity plays a major part of making proper neck adjustments, this is the best way of obtaining the most accurate leveling results. Think of it as a ‘poor man’s Plek machine’ that can achieve the same or possibly better results for dressing frets. Sure, it takes three to four times as long to perform the job, but it also doesn’t require taking a mid five-figure bank loan, take up a large chunk of shop space, doesn’t level the fingerboard itself like here, and doesn’t polish the frets automatically either. But also in the same way as the Plek, the end results are still dependent on the experience and input of the operator.

These original frets are shot! They’ve been dressed many times over the years, and are now so low with pretty much no crown left that bending strings is very difficult, and intonation will also suffer.

Showing one of the frets after removal puts things in perspective. Now that’s worn out!

The fingerboard after heating and pulling all the frets.

After setting up and optimizing the neck in the jig using the all-important notched straightedge, it was discovered that there was a hump in the fingerboard around the 3rd to 5th frets, and the classic ‘rising tongue’ which was very pronounced on this guitar. This particularly affects how low you can get your action in the upper registers. Here we do a few passes with the leveling beam and 180gt to make these humped areas more distinct before marking them for removal. The key to getting perfect fret jobs is directly dependent on fingerboard preparation. Think of it the same as building a house: it’s only going to be as good as the foundation it’s built on – being perfectly straight and level.

The hump areas to be shaved are marked clearly in white pencil.

The rising tongue being the worse of the two humps, we speed things up by using a cabinet scraper to remove a substantial amount of material. It was determined that we needed to level from the 15th fret upwards.

We keep re-marking and removing material carefully as we go to avoid the mistake of removing too much. Careful attention to scraping approximately and evenly across with the radius is also very important. The whole board will be re-radiused after the leveling has been completed properly.

Checking the work with a short straightedge in the area after every few strokes. The visible gap shows just a little left to go from the 20th up to the end.

I wanted to point out here about a common mistake I see those learning to level frets: doing it suspended (horizontally on a bench top with just a neck rest behind the nut or lower area) without adding support along the middle – if not preferably the whole length of the neck. If not firmly supported, the neck flexes with each pass of the leveling beam, file, or radius block, and can give skewed and inaccurate results overall. Pretty self defeating really.  Here the neck support rods do the job of keeping the neck from undue flex while leveling. While most average hobbyists learning to fret dress don’t necessarily need the extreme accuracy of the neck jig, you can still get good results utilizing this or this to help add the necessary support while working.

Now attention is given to the lower humped area with the same method.

Here you can clearly see the dust-filled depressions (the lighter brown areas) in the fingerboard from 42 years of playing wear. For a clean, like-new fret job, you must keep going with the leveling beam, constantly checking with an accurate straightedge, followed by a radius block (12″ in this case) until the entire board is evenly done.

The end result: like our earlier mentioned house foundation, is now perfectly leveled, radiused, and ready for the next step – preparing the slots for the new frets.

An old technique for smoother insertion of fret tangs is to slightly bevel the opening edges of the fret slots with a triangle needle file (at left). Doing this first (not too much though!) before enlarging or cleaning out the slots also has the added benefit of helping to greatly reduce chipping from the tools while doing it.

Since this is bound fingerboard, extra care must be taken when beveling the slots not to saw into or through the binding that is blocking the end.

After beveling the openings, the slots must be cleaned out of old glue and dust, and possibly widened or deepened at this point if one is using a substantially larger fretwire. This particular .020″ razor saw is modified for this exact purpose on bound fingerboards where a normal slot saw cannot be used, and has two small sections with opposing teeth to cut on both push and pull strokes.

Here we’re using a ‘slot claw’ pick to clean out the slots fully, right up to the inside edges of the binding. You can see the old, crystallized hide glue coming out of the slot.

Checking the slot depth with calipers,making sure to go along the whole length of each slot.

The fret tangs are .062″, and I like to give an extra thou or so for wiggle room and internal wood swell in the slot while the glue infuses. The width is checked after cleaning with a feeler gauge for a target width of .023-.024″.

Our ‘foundation’, the fingerboard, is now finally complete and ready for fretting :-)

Now it’s time to prepare our fretwire, in this case we’re using a ‘medium-jumbo’, nickle-silver wire with a crown size of .092″ W by .048″ H.  First we clean any excess tooling oil off the wire with naptha and a paper towel (for good glue adhesion) before running 2+ lengths through the fret bending roller.

Gibson uses a 12″ fingerboard radius, and the conventional method in wire prep is to slightly overbend it so that helps to prevent the ends from springing up after it’s seated into the slot.

So we cut each fret to length with a few mm’s of overhang, and keep them organized in order before installing.

But wait, there’s more! Now because we have binding to deal with, each fret’s tang must be clipped to allow the crown to slightly overhang onto the binding. Normally Gibson installs binding over the fret ends and then scrapes the binding height between the frets down flush with fingerboard, leaving ‘nubs’ covering the fret ends for a nice clean look. On a newer guitar with most or all of the original nubs still intact, I would cut the fret to fit inside the nubs for an original, stock appearance. This was impossible in this case, as pretty much all the nubs had been filed away from the multiple previous dressings, so the frets were installed in the traditional way for bound boards.

The little ‘1/3 size’ 22nd fret will require some extra attention from the rest, particularly when dressing the inside tapered end.

Depending on the job, sometimes I press-fit frets, and sometimes I will do it the old-school traditional way and seat them by hammer method, as I will do now and how Gibson did back then. And as they did for nearly 100 years, I will use hide glue in the slots for extra security. CA and Titebond-type glues are also frequently used (epoxies are not recommended), and I still use CA for securing fret dresses and quick fixing loose frets, but on whole refrets I prefer to use good ‘ol hide glue like Gibson did. It does hold the fret very well (you see very few pre-80’s Gibsons with lifting frets), is easily removed with heat, and because it dries to a very hard, crystalline consistency, it does seem to transfer string contact vibration much better than the other typical glues used (which = better tone).

First, small cork pads are inserted firmly between the head of the support rods and the back of the neck, to act as shock absorbers in preventing the possibility of denting the back of the neck while hammering-in the frets – with really not as much force as it sounds. A small amount of hide glue is wicked along the length of the slot, the fret is then held in place and given two taps on either end to seat-down the ends first, then the center, followed by tap-seating along the whole length. You must move fairly rapidly at this initial seating, as the exposed glue will stiffen fairly soon.

Once all the frets have been basically seated fully into the board by eye, we have some time before the hide glue starts to set fully. We now backtrack with a fretrocker over all the frets on the entire fingerboard and gently tap down any last remaining high spots that didn’t get seated fully with the initial run. This extra step will ensure that the amount of metal removed in the final leveling will be absolutely minimal, and will keep the best crown. The neck will now sit and harden for 24hrs, and any of those minuscule high spots that may still remain will be taken care of with the final, light leveling a bit later.

The next day, the protruding fret ends are cut flush with the edge of the fingerboard.

Our little 22nd fret end needs to be filed at the right angle to match the end of the fingerboard first, and then will be shaped and rounded using a fret-end rounding file along with the others.

The main workhorse tools for the bulk of the shaping: the leveling beam, flush-cut file for the ends (level & bevel), and a radius block for both the fingerboard and the fret tops. Papers used generally are 3M Gold 180, 320 & 600gt for the bulk of the shaping.

After a very light leveling, end dressing, crowning and then polishing are the stages. My three favorite files for fretwork; offset diamond file for over-the-body/tongue, the small fine end-dressing file, and my good ‘ol trusty, modified triangle file for major crown shaping or touch up.

Depending on how much time I have or how fine I want to go, I’ll handle the time-consuming final polishing a couple of different ways, but in this case I wanted to do each one by hand at a time. Here you can see the two polished frets (left) compared to the untouched, lightly leveled ones on the right as an example. I’ve removed the protective masking tape to see properly.

I used to use a buffing wheel and compound sometimes on the final buff, but I ran into some hassle and problems with doing it that way; mostly I found that in some cases the heat generated by the wheel’s friction on the frets would cause some of the still-new glue to loosen slightly in random spots – basically undoing the perfect leveling job I just spent hours working on! :-/  Now, although more time consuming, I polish all the frets by hand using the fantastic Micro-Mesh papers all the way up to super fine 12000gt for results that feel like glass and look like chrome. Anyone who states that only stainless steel frets can achieve this level of smoothness are dead wrong – it’s just that most manufacturers or repairmen don’t put in the extra effort to get it to this point. I do.

The refret is basically done now, and the fingerboard will get re-hydrating conditioning during final setup.

Before I start to setup this guitar, there’s a couple of issues that need to be addressed beforehand. First, is the mangled height adjustment screws on the original Schaller wide-body (or “Harmonica”) Tunematic bridge, which are so badly worn that adjustment is nearly impossible with a normal flat-head screwdriver for which was intended. This pic was taken during the inspection before commencing work. It was also mounted backwards, as the saddle intonation screws are better accessed facing back towards the tailpiece on this model.

The old, mangled slots on the head are first carefully (not too far!) ground down on a disc sander.

Then secured in a vise and a new slot is cut into the brass head with a diamond cutting wheel in a Dremel.

And now it’s ready for more years of adjust-ability. The bridge has now been turned around, with the screws facing back, and the saddle’s taper is also correctly facing back with the string’s break angle. :-)

Here’s a closer look at the controls and their functions. Very cool in an experimental way.

And here’s our other small issue to attend to; the area surrounding the output jack on the pickguard has ‘stress shatter’, and is very weak when a cable is plugged in – you can even bend the plug around with one finger – not good. We’re going to have to ‘MacGyver’ a repair to help strengthen the area, as obtaining a replacement control plate for this rare model would be next to impossible.

First the jack was unscrewed from the celluloid plate, then was held together underneath with strong fiberglass tape, infused with CA glue into the cracks from the top, then two 3/8″ washers were used to sandwich and reinforce the jack in the plate. Much, much stronger now.

And seen from the face.

Since we had this rare bird open, here’s a shot of it’s (confusing, lol) wiring – completely original with virgin solder joints and no mods.

And now after the fingerboard has been re-hydrated…

A closer peek..

And after a complete setup, this old girl is ready for many more years of play!