Floyd Rose Bushing Repair

A few months ago I bought a 1990 Japanese Fender Stratocaster with an Official Floyd Rose tremolo.  At £250 I figured I couldn’t go wrong, and didn’t give it a thorough inspection before buying.  When I did take a look at it I realised one of the bushings for the posts was loose.  Unlike most other guitars, the bushings aren’t pushed into a solid section of wood, instead there are blocks glued in at the front of the bushings.  From the paint job it looks like the guitar was made that way, rather than it being a fix.  In any case the bushing on the post next to the high E string was loose.

I’ve spent the past four months trying to fix this, and only just found something that works (i.e. the guitar stays in tune as it should).  Frustrating, but something of a learning experience too, so I’m going to share what didn’t work as well as what did.

1. Cocktail sticks and wood glue

The first thing I tried to was to wedge in the bushing with wooden cocktail sticks and keep them in place with wood glue.  This worked to a point, but really exposed the real problem – the wooden block was moving forwards.

2. Re-glue the wooden block

Eventually the wooden block became so loose I could remove it.  I then cleaned off the old glue with a stanley knife and tried to glue it back in.  The first time I used generic PVA wood glue, and didn’t clamp.  This didn’t hold – fitting the tremolo and tuning up the post moved forwards.

After doing a bit of reading I convinced myself that gorilla glue was the thing to use.  Gorilla offers several types of glue – a wood glue, polyurethane glue and a cyanoacrylate (superglue).  I bought the polyurethane glue after reading it will expand and fill cracks, seemed to be what I needed.  It wasn’t – the glue lasted for a few days at full tension before the block shifted forwards again.

After doing some more reading of forum posts, in which titebond was recommended as the glue of choice for luthiers.  I also bought a “deep throat” G-clamp to hold down the block in place for 24 hours whilst the glue dried.  This time the block held, but the bushing was still loose because the hole was too large.

So the moral of the story here is that the correct glue, and clamping are a must.

3. Epoxy…

The correct solution here was to drill out the holes, fill them with hardwood dowels, then re-drill the bushing holes.  However I was reluctant to do that, so I tried to fill around the bushings with epoxy.

Once again this failed – the epoxy didn’t even dry properly.  Either I didn’t mix it correctly, or because the house was cold the epoxy didn’t want to set.  I didn’t apply some heat to try to get it to set, but even if it did this isn’t a good method because the bushings shouldn’t be glued in.

4. Drill, dowel, repeat

My main reasons for delaying this [inevitable] step was that I didn’t have a drill press, and I wasn’t sure I would be able to accurately drill the holes.  But with no alternate options I figured I may as well give it a go – worth thing that can happen is I will need to give the guitar to someone more qualified…

In preparation I purchased a portable drill press to use with my cheap electric drill so that it would drill reasonably vertically and a flush saw.  I also bought some 15mm hardwood dowels (oak I think – more on this later), and borrowed a 15mm drill bit from work.

I first drilled the existing bushing holes out to 15mm, then filled these with the dowels glued in with titebond.  24 hours later I then drilled the centre of these dowels out to 25/64″ (approx 9.9mm), working my way up from 4mm.  My cheap electric drill had some wobble though, and so the holes ended up being a bit larger, so I mixed some sawdust with titebond and coated the holes.  24 hours after that I hammered in the bushings.  They were tight, which seemed a good sign.

However, after stringing up it still didn’t stay in tune!  The wood dowels were not hard enough and the bushings crushed the wood at the front of them.  I obviously didn’t do my homework about what dowels to use – since then I have read that maple dowels are the ones to use.

5. Aluminium tape

I had read somewhere that aluminium tape can be wrapped around the bushings if they are a bit loose, and I happened to have some of this tape.  It worked reasonably well, but the tape slipped up when pushing the bushings into the holes, and consequently the bushings ended up tilted once I strung up.  However they didn’t push forwards into the wood any more, so I would recommend this fix if your bushings are a little loose.

6. Carbon fibre tube

Finally, the method that so far seems to have worked.  After realising that the wood dowels weren’t hard enough, I started thinking about more exotic materials – fibreglass and carbon fibre.  I found a 10mm ID 12.7mm OD roll-wrapped carbon fibre tube which seemed suitable and reasonably priced (£10), and figured it was worth giving it a try.  The roll wrapping of this tube means that it will stand up to compression/crush forces more so than tubes made only with longitudinally running fibres.  Also the tube is the right size for the bushings (10mm ID).

Drilling the bushing holes out to 12mm

Drilling the bushing holes out to 12mm

First I drilled out the bushings to 12mmm – because of the wobble in the drill I used a smaller size and then carefull enlarged until it was a tight fit.

Checking the length of the carbon fibre rod

Checking the length of the carbon fibre rod

I inserted the carbon fibre rod into the hole and marked out a line where it was flush with the surface.  After removing I cut it with a hacksaw and then did the same for the other hole.

Roughing the rod surface

Roughing the rod surface

Epoxy was the glue of choice for gluing the tube to the wood, and it needs a rough surface to adhere to.  So before inserting each tube I roughened the surface with a file.  After mixing the epoxy I put a small amount in each hole and smeared it around the edges.  I then pushed each tube into its respective hole, using a hammer and wood block to tap it in all the way.  Finally some of the glue was spread around the top of each tube to fill the gaps.

Epoxy glue in and around the hole

Epoxy glue in and around the hole

24 hours later the epoxy hadn’t set.  The instructions said 16 hours so something wasn’t right.  I had mixed well, so figured it had to be too cold for the epoxy to set.  I used a hairdryer and also put the guitar in front of a halogen heater for a while (being careful not to damage the paint).  This did the trick and 24 hours later still the epoxy was set and it was time to push in the bushings.  This was actually quite tricky because the 10mm holes were too small, and the carbon fibre being harder than the wood didn’t deform as much.  After careful hammering with a wooden block I was able to get each bushing in.  I then re-strung and set up the tremolo.  FYI I’m using a tremolo stop (piece of metal in the spring cavity) for setup, and because I want to be able to tune down to drop-D I keep the tremolo set for divebomb only rather than fully floating.

8 days later the guitar is still in tune, there’s been a little bit of settling (10% of a semitone), but it all seems good so far.  I’m not sure if the carbon fibre does much for the tone – it is harder than the basswood body, but there isn’t very much of it in there.  One small issue is that the high E stud is about 1mm closer to the nut than it should be, but that should be correctable by adjusting the intonation.  I use The Key to intonate the tremolo, that combined with the tremolo stop makes it a fairly straightforward job.  Failing that I can always drill out to 15mm again, re-dowel and then make sure I mark out the holes correctly!