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| To: | |
| a) The Body | b) The Neck |
| c) The Tremolo | d) The Pickups |
| e) The Bridge | f) The Machine Heads |
| g) The Springs | h) Alan Marshall |
Intro:
Design and construction of this guitar has provided a number of interesting, and at times frustrating challenges.
The first of these was quite simply where to get accurate information about the original. There are no working drawings that I have been able to find, only a general layout drawing that came to me via a very devious route. This drawing shows the rather strange construction of Brian's own guitar, but has no dimensions except for the neck angle, which after further research proved to be wrong.
I already knew the scale length to be 24", and as this drawing seemed to be accurate regarding this, and "looked right", I used it to produce templates for the body. A bit of surfing soon revealed information on neck dimensions and Phil provided some additional material.
Some of the dimensions for things like switch positioning, tuner spacing and the like, were calculated by scaling from photographs, others simply an educated guess, but those which are more than cosmetic, worked out very carefully to make sure that it all worked first time.
Body Top
2 piece Mahogany Bound with grained
ivoroid. Semi-solid construction with additional routing to give
rear access to the tremolo springs, and to facilitate the fitting
of the heavy brass block which carries the knife edge, and provides
the fastening for the trem springs. Front tremolo cover plate
is recessed to allow string changes without removal.
Neck Top
2 piece Mahogany with rosewood
fingerboard glued into the body without bolting through. Truss
rod is Northworthy's own double acting type, which allows any
gauge of strings to be used.
Tremolo (More...) Top
Custom made to the same general
pattern as the original. It is fabricated from stainless steel.
The main body is in one piece, but with the thickness doubled
up behind the groove for the knife-edge, to minimise any chance
of fracture or bending at this point. (I understand that the Guild
version is known to be weak here, and that Brian has broken 2
of their tremolos). The hardened and tempered gauge steel knife-edge
is secured to a rebate in the brass block by three M4 countersunk
head socket cap screws. The rebate ensures that there can be no
forward movement of the knife-edge, and combined with the screws,
should give the best possible transmission of vibration (and thus
sound) through to the body.
Pickups Top
Three Burns Tri-sonic pickups
are fitted as on Brian's own guitar. These have been artificially
aged by immersing the magnets into liquid nitrogen and boiling
water alternately several times to try and mimic the effect of
thirty odd years of use. They are wired as the original with individual
on/off, and phase reversal switches. Because of difficulty obtaining
these switches with sufficiently long knobs, they are mounted
directly onto the scratch plate, rather than an aluminium plate
as the original was. The pickups themselves are screwed directly
to the body, without any kind of spring or cushioning, but with
mahogany spacers set under them so as to adjust their heights
to give a consistent output from one to another. The whole of
the underside of the scratch plate is coated with copper foil
and earthed to the strings and controls to minimise noise. These
single coils, are not known for being particularly quiet!
Bridge Top
This is a standard Schaller STM.
It was not considered that the expense of producing a custom bridge,
to what looks like a slightly odd design, could be justified when
a standard unit that is known to perform very well, and looks
fairly similar, could be obtained.
Machine
Heads Top
The machine heads were Schaller
M6 Mini's, but Phil would like to thank Mark Reynolds for giving me the correct
Pearloid
buttons to round it off.
The 6th string has a Hipshot D-Tuner fitted to assist Phil with 'Fat-Bottomed
Girls'.
Which brings me to the question of the...%$!**^%$ ...
Tremolo
unit. Top
My brief was to make it however I wanted, so long as it worked
properly, and looked like the real thing. Well that seems like
no big deal to anyone who has worked with and on guitars for the
last 16 years or so!
The layout of the tremolo as mentioned above, follows the main design points of the original, although I chose to mount the knife edge on a brass block, rather than screwing it to an oak block let into the body, and then veneered over, so that in the event of this becoming worn or damaged, it could be replaced without having to tear the front off the guitar!
But then came the springs. Top
The springs have proved to be the biggest headache of all.
The information I had was that they were motorcycle valve springs. But what from? A contact in Jersey found out via a friend who knows Brian's guitar tech that they came from a 1926 Panther, but didn't know what model, or if they were valve or clutch springs. Brian had long since forgotten!
So on to the phone to a friend who has been known to restore the occasional vintage bike, who gave me the number of the Panther Owners Club spares Secretary.
Armed only with a vague indication of the dimensions of the springs, and no idea of the rate, I rang the P.O.C. man. I gave him the scant information I had, and he promised to look through his parts lists to try and find a likely candidate. About a week later, he called back to say that the only ones he could find that were close to the description I had given, were from a 1928 Panther 600 clutch assembly. A week or so later they arrived, and it seemed obvious that they weren't going to be strong enough. With only 2 strings fitted, the trem bottomed, and tightening the bolts just caused the springs to become coil bound.
Back to the phone, this time to a major spring supplier. No, they had nothing like it in their catalogue, but they could make them for me.... minimum order 5000.
Back on the phone again, this time to a specialist spring maker in Birmingham. Having found out the information they required, out came the micrometer and calculator.
Check the string gauges . . .calculate the overall tension of the set with the guitar at pitch. The 24" scale means that manufacturers Tension Tables are useless . . . calculate the resultant force on the tremolo, allowing for the angle that the strings actually pull at . . . calculate the moments about the knife-edge to get a balancing figure for the spring rate in pound/inches . . convert this to Newton/millimetres . . .drink coffee, smoke 2 ciggies, scratch head, and recalculate all of the above to check that all was correct.
Decide on free length, working length, movement required, and preferred size Contact spring maker with spec and order custom springs . . .go weak at the knees when told the price . . .wait 2 weeks, and then contact spring maker again. "Oh, sorry, your order seems to have gone astray, can you give us the spec's again!?" Mutter mutter . . .wait 2 more weeks, springs arrive . . . fit springs, string up, adjust trem... B$*!^*RDS, they're still not strong enough.
Cry into beer. Consider emigrating, joining Salman Rushdie in retreat. Bungee jumping without elastic, etc.
Package arrives with note from vintage motorcycling friend saying "Try these!, They're a bit big but..."
Make up collars to fit new huge springs as the mounting bolts fall through the centre . . .swear vigorously as I discover that I can't get the mounting screws past the springs to fit the trem . . . disassemble, drill new mounting holes . . . swear a whole lot more, putting it back together again.
Fit back into guitar . . .string up . . .hold breath . . . . .
. . . . .Eureka! It works . . .faint in amazement.
At last it was ready to fit the covers and ring Phil with the news that his guitar was finished and ready for collection.
Guitar making may seem a pleasant job, and one which many of you might like to try, but believe me, it can be very, very trying at times. Still, it always gives me a great buzz to see and hear something that I have made, giving pleasure, not only to the owner, but in the hands of someone as good as Phil Teague, giving even greater pleasure to so many others.
Special thanks are due to:
i) Phil Teague, for ordering the guitar in the first place and his subsequent patience and understanding during the long gestation period.
ii) Phil Denton for finally coming up with the springs that made it work in the end. (They are from a competition clutch out of a Honda CR125 RV Trials Bike).
iii) Ian Dugini for providing the bulk of the information about the original guitar.
