du Pré Guitars
The du Pré Guitars Gruffbastard Baritone build diary. See the Gruffbastard being born and see what goes into hand building a top quality instrument.
Dying the body
The body, after being dyed black. Before this stage (not pictured) the grain was raised by wetting the wood which swells the cut ends of the grain. These then make the surface all rough and fuzzy. The body is then smoothed down with wire wool. This ensures that next time the body is wetted (with dye) the grain does not rise again. The body was initially dyed green but we were not at all happy with the colour achieved, so we went with plan B; an all black finish. This has 4 coats of black spirit dye to ensure a good deep dark black that fills the grain. The first three coats are applied with sponge, and the final coat is applied with wire wool. Every stage of the finish process needs to be left dead smooth ready for the next stage. Spirit dye is messy, flammable and smells dangerously strongly like marker pens and stains everything it touches, which is sort of the point. After the final coat of dye, the body is left for an hour or so, then wiped down with a rag to remove any excess dye that may have pooled. Even though the dye is supposedly quick drying, the body is now left to dry thoroughly for a couple of days before applying the Danish oil.
The neck
The completed neck. The wood is wenge, with an ebony fingerboard.
The headstock. Notice how long and straight the grain is. This bodes well for a very stiff neck. The grain is alternately pure black and chocolate brown. It looks very tasty.
A close up of the wood. Wenge is actually quite a rough wood, with deep pores. This is very different to a neck wood like maple, which has virtually no pores, and can be sanded almost perfectly smooth. The rougher surface of the wenge has the effect of reducing the surface contact area with your hand, resulting in less friction, and a very fast feel.
The pickguard
The reverse of the pickguard. The holes have been drilled for the volume and tone pots and the three-way switch. the volume and tone holes are equally spaced on a slight curve which follows the curve of the scratchplate. The bottom half has been shielded with thick copper shielding foil. This looks very pretty, and it's a shame no-one will ever see it. One day I'd like to do a copper leaf covered guitar. The copper foil is much thicker than your normal household tin foil, and is sticky backed. It curls up very easily and although it makes no difference whether there are creases and folds in it, it is very satisfying making it as flat as possible. If you are the sort of person who likes to smooth out foil sweet wrappers, this is a great job. On the other hand, the cut edges of the foil are incredibly sharp and it's very easy to pickup very painful paper cuts from it.
Treasure!
The treasure chest for the Gruffbastard project! It is very easy to lose hours of your life pawing through all this really great stuff. In the picture you should be able to spot the following:
- A brace of Bare Knuckle Black Dog humbuckers, with mounting screws and springs (held conveniently together by the magnets in the pickup).
- Some 500K logarithmic potentiometers, for volume and tone controls
- A RS Musicaps capacitor. (only one of two pictured.)
- Neck plate with screws.
- Strap pegs, with screws and felt pads.
- Jack socket, mounted on an oval mounting plate.
- Pickguard screws.
- 3way switch
- Wire. Black and yellow. I use yellow for all the hot wires, and black for all the earth wires.
- Tuner mounting screws (Tuners not pictured, I'm holding that money shot back till later. You just wait.)
- Knobs for volume and tone pots.
- Front and rear string ferrules.
Bridge inserts and ferrule holes
The threaded inserts for the bridge posts have been installed. Notice the wire just visible in the control cavity. This is the crucially important earth wire, which needs to be fed into the bridge post hole before pressing the insert in. This is then held captive and in close contact, which then earths the electrics to the bridge and therefore strings. This makes sure you never get the annoying buzz that goes away as soon as you touch the strings.
Also in the picture you see the holes that have been drilled for the ferrules that the strings will pass through before being anchored in the back of the body by a more substantial set of ferrules.
Mounting the tuners
The tuners (Gotoh 510) have been been mounted. They simply need offering up and tightening up finger tight and lining up by pushing them all against the same straight edge. Then the holes for the fixing screws can be marked with a bradle. All the tuners are then removed and the pilot holes for the screws are drilled, before putting them all back on, and tightening everything up. A pretty simple and rewarding job.
Loading the pickguard
The Bare Knuckle Black Dog humbuckers, volume and tone pots and 3-way switch are mounted into the scratch plate. Mounting the pickups is a three handed job, which requires the small spring to be compressed with one hand, the screw to be fed into its hole with your other hand, and tightening up the screw with a screw driver in your other hand.
The reverse of pickguard. The wiring has now mostly been done. The second tone capacitor still needs to go in. Also the earth wire that runs to the bridge and the wire to and from the jack socket also still need doing, but because they effectively join the scratchplate assembly to the rest of the body they won't be done until the final assembly.
More work on the finish
The body has now had 4 coats of black dye, 3 coats of danish oil, and one coat of 1/3 dye and 2/3 danish oil mixture. The final few coats were applied with very fine grade wire wool to get as smooth a surface as possible. Once this had all dried, the beeswax starts going on. The picture is after 2 coats of beeswax, and a good sheen is building up. This will be regularly buffed as it completely dries out to get the best possible shine. The grain is still quite apparent which I am pleased with. Although it's completely black, it's still very much a piece of wood.
Ferrules
Once the finish is complete, the ferrules on the front and rear of the body are installed. Some more careful drilling is required to make sure the holes are the perfect width and depth to accommodate the ferrules. They need to be tight enough so the ferrules won't move once they are pushed in, but not so tight it is impossible to push them in without using extreme force. This needs to be done with a drill press / pillar drill because it is essential the holes are perfectly vertical. If you try and do this freehand, the entry holes may be in a straight line, but the exit holes are likely to be all over the place. Once the holes are all drilled, it's a pretty simple job of bashing in the ferrules, taking care not to mark the finish!
Nut job
The Earvana Compensated Tuning System nut was then installed. As with all these things it was never as simple a job as it should have been. A lot of filing and fiddling was necessary. The installation instructions on Earvana's site are very good but a degree of filing whilst the parts are attached to the neck is necessary. This is not ideal because there is a considerable risk of marking the neck or finger board with the file by mistake. Extreme care and caution is essential to prevent this.
The Earvana nut is designed for use on a normal scale neck and is optimised for 10-46 gauge strings. I'm using a longer baritone neck with a scale of 28 5/8" and 14-68 gauge baritone strings so I am not expecting as much benefit from the intonation, but there should still be noticeable improvement to the intonation. One further modification to the nut was required because I am using strings with a wound third. The compensated nut is intended for use with an unwound third string. It was a pretty simple fix to file back the "step" in the nut on the third string a little to accommodate this.
Wind your neck in
Fitting the neck is the simplest and most rewarding job. You suddenly go from being surrounded by parts to having something that clearly has the potential to be a musical instrument, and only now can you get a feel what what the true character of the instrument is going to be. Although this is a simple task involving 4 screws, there is of course a complication caused by the "comfort contour" heel carve. This removes some of the bulk of the heel joint and means that the heel is noticeably thinner at the neck end. This in turn means the standard length screws are now too short and if they were screwed in would pop out of the front of the fret board. This would be clearly be a day ruining event.
This picture shows the joint, and also shows off the contouring on the rear of the body.
Final assembly
All the major tasks are now all done. The scratch plate loaded with all the electrics can now be installed, the ground wires and jack socket wires are hooked up which permanently joins the scratch plate assembly to the body. The jack socket is fitted to its plate, and the plate is screwed on. However, only a fool would start doing the final screwing down of all the electric bits until some thorough testing has been done! Even though there are no strings attached yet it i still possible to plug into an amp and prove that the switch is the right way round, the volume and tone pots work as intended.
Other small jobs such as installing the strap pegs, string tree and slotting the bridge on are also done at this stage. Once everything is done the very last job is put some strings on see how it sounds!
Go back to the main Gruffbastard page to see the finished article.