I recently visited Martin Simpson at his home in Sheffield, taking him the Anniversary Martin Simpson guitar he fell in love with on a recent visit.  He intends to use it for recording and playing live.

Here are photos I took of Martin playing the guitar in his home.  It sounded wonderful; it took me back to how Martin sounded playing my guitars years ago.  His wife Kit echoed my thoughts, saying ‘Martin, that sounds like you’.

The guitar is my 40th Anniversary guitar number 4, built in October 2022. I’ll add another pickup to the existing Highlander later this summer.

Why is there a dulcimer in my ear?

Danny is currently supporting Richard Thompson on his UK tour.
Tour dates: https://www.richardthompson-music.com/tour-dates

1995 neck mahogany

1995 Model 0 with Brazilian rosewood back

Old dark dense mahogany

Honduras rosewood

Information about St Luke’s Hospice here:  https://www.stlukeshospice.org.uk/

Truss-rods can fail. Sometimes because of over-tightening, sometimes when the hexagonal keyway has been rounded (with an undersized or worn allen key), sometimes when they rust and seize after being kept in damp conditions, and sometimes because they were under-engineered in the first place.  And sometimes for no obvious reason.

I now grease all truss-rod threads, so that even should the guitar be kept in damp conditions (which of course it shouldn’t for several reasons), the threads should not rust. And should turn more easily in all conditions.

Daniel Clark recently sent me his 1989 Model 1 guitar with a non-functioning truss-rod.  This truss-rod was made of a steel rod in an aluminium channel, as were most at the time of building. One end of the rod is fixed to the end of the channel, the other is threaded with a long Allen nut working against the other end of the channel.

Tightening the long nut against the threaded end of the rod shortens it, and as the channel is of fixed length, the channel has to curve. Because the truss-rod is tightly enclosed, it bends in its entirety with the longer channel back to the outside of the shorter rod, bending the neck with it.

Old type steel and aluminium truss-rod

Modern truss-rods are simpler and more compact.  The rod is threaded at both ends, one standard and one reverse thread, and runs through long nuts attached to each end of a narrow flat steel bar. So turning the rod (with an Allen key in the rounded end) one way shortens it (and the other way lengthens it) against the fixed length bar, thus bending it.

Not only does this have less work to do (not having to bend the sides of the channel), it also eliminates the problem caused by different expansion rates of steel and aluminium. It also permits pulling the neck forward if required.

Modern double action all steel truss-rod

When Daniel’s guitar arrived, turning the long Allen nut was effortless but had no effect.  So the truss-rod had to come out.

The standard procedure is to remove the fingerboard (complete with frets), so the truss-rod can be changed, replacing the fingerboard afterwards.  My problem with this method  is that it damages the finish, not only between the fingerboard and the neck but also, more importantly, between the upper portion of the fingerboard and the soundboard. Touching up old finish on a soundboard is a problem, it will always show.  So I decided on a different method.

Rather than remove the whole fingerboard, I take out the frets and cut a slot in the fingerboard above the truss-rod so I can remove and replace it. I do this with a router mounted on a simple plywood jig.

1. Here is the jig mounted over the fingerboard.  I removed the frets and routed out the area above the broken truss rod, enabling me to lever it out. The mahogany neck is visible at the bottom of the slot. The old truss-rod is alongside.

4. I trimmed the ebony insert down to match the level of the existing fingerboard, cut the fret slots in it, and replaced the centre Mother of Pearl dots.

5. The old frets were worn, so after checking the fretboard is level, I replaced them with Evo Gold fretwire.  This is much harder than the original nickel silver and will last much longer without pitting.

6. Now strung up, it needed just a tweak on the truss-rod, and it’s perfect.  The only way the repair shows is that the new ebony is a little blacker than the original, but a quick oiling minimizes even this. With the 3rd and 4th strings over the joins, it is almost impossible to see. And no damage to the finish.

Click on the image to see a larger version.

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Douglas Fir is a lovely honey coloured softwood.  When close grained, it makes excellent guitar soundboards. These give a strong, characterful bass and a clear treble.  Being light and stiff, Douglas Fir also makes excellent brace wood.  Here are rough cut bracewood pieces resting just above my warm workshop stove.

It has been suggested that when Stradivari first set up building violins he was short of well seasoned spruce (he will have used Italian spruce coming from the north), so put less seasoned wood into his chimney, letting the hot fumes ran past the face of the soundboard wood and drying it reasonably quickly. Kilned wood is dried much faster by high temperatures which changes the chemistry of the wood in a way air drying and the relatively slow drying in the passing warm fumes from a stove or fire do not.

I should add, I don’t know how reliable the Stradivari theory is.

When having a classical guitar built (in a time before I was building instruments), the sides picked were hanging in front of a radiator, so drying in a similar fashion.

Having bought three blocks of Douglas Fir for braces, I cut the first into slightly oversize pieces, taped them together and placed them on my warm workshop stove, left on day and night. They were edge on to the heat, allowing the warm air to run past the face of each brace in much the same way as Stradivari is thought to have dried his spruce.

After a few weeks, the wood is dry and resonant, ringing beautifully when tapped.