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Old 11-28-2017, 01:27 AM
dantin dantin is offline
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This is George Lowden's reply in 2003 to neck reset question:

https://groups.yahoo.com/neo/groups/...s/topics/15099

Perhaps I can answer this:

The usual problems which eventually result in a neck reset are:- 1) The
neck angle coming up over a period of time due to the compression of
the 'shoulders' of the dovetail under long term string tension, 2)
sinkage of the sound-hole area as the guitar soundboard is compressed
length-wise under string tension, (this also changes the neck /
sound-box geometry) 3)... rarely.. the neck angle not being right in
the first place! 4) ....rarely again... the permanent swelling or
shrinkage of the soundboard, causing the bridge to either rise or fall
to a significant extent. Sometimes a neck reset can be necessary when a
mild & combined case of some of these problems occurs.

Back in the mid '70s when I was designing the Lowden guitar ( at that
stage the O series only) I noticed a tendency for some of these
problems to happen pretty early on, so I developed a number of
solutions as follows:

1) The dovetail joint compression: I removed the gap at the front of
the dovetail always present in production guitars and I made sure that
the shoulders of the dovetail matched the curvature of the guitar
sides. This increased the surface contact area within the dovetail very
significantly and eliminated neck angle instability through dovetail
movement, totally......HOWEVER.. it also made it infinitely more
difficult to inject steam to loosen the joint to remove it, if
something did go wrong! The gaps present in other acoustics both
contributed to the potential need for a neck reset.... and also
facilitated the reset itself because the gaps in the joint made it
easier to loosen the joint! I took the view that it is better to
eliminate the causes of neck resets in the first place. I am also aware
that maximum wood to wood contact within a guitar, helps promote
sustain, amongst other things. Note, the gap at the front of the
dovetail and the scalloping away of the shoulders of the neck, both
make it easier and quicker to fit a dovetail joint in a factory
situation.

2) I designed the A frame bracing (1976-1977) with two structural
braces running down either side of the sound-hole (so stabilising it)
and continuing up under the fingerboard actually into the dovetail
joint itself so that the neck wood actually butt joints with the A
frame bracing at the face of the dovetail. Sound-hole sinkage was also
eliminated as a result.... and the neck had a direct link with the
soundboard bracing itself (no bad thing) A couple of other companies
introduced A - frame bracing in the early nineties, but I am given to
understand that they do not actually continue the braces the whole way
into the dovetail itself.

3) Apart from human error from time to time, generally the neck angle
on early Lowdens was a little flatter (about 0.75mm positive measured
at nut) whereas over time I gradually increased this to more like
1.25mm positive which creates a higher saddle. This gives more
adjustment to lower the action later if it should be necessary. It
sounds like the guitar you mention has a slightly flat neck angle.

4) There's not a lot you can do about extremes of humidity or dryness
except control the humidity where the guitar is kept. This can have a
very marked effect on a guitar's action and sound. if the guitar is too
'wet' the action will be too high (or the saddle too low) and the
guitar will sound tight and possibly lose bass. if the guitar is too
dry the action could become too low and yet the guitar will sound good
(even if it is buzzing a little) Control humidity to about 45 - 55% RH
if you can.

So where does all this leave you, when considering a Lowden guitar
which may need a reset? Firstly, it is difficult to remove most lowden
dovetails because there should be no gaps to work with. Therefore
experience has shown at the factory that it is less expensive to simply
replace the neck itself.

However, it seems most likely that the neck angle was always a little
flat seeing that neck angles on Lowdens do not tend to move. Therefore
if the saddle is just too low then there is another cheaper solution
which involves re-working the bridge in situ. The purpose is to lower
the position where the strings emerge behind the saddle which means you
can lower the saddle and still maintain a good rake angle for the
strings. This work takes a couple of hours or so, but is effective
where the problem is not too severe. A good repair person can certainly
do this without excessive cost ( probably about the price of a re-fret
or so). I am available to advise any repairman who needs to carry out
this work,

Hope this info helps,

regards,

George
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Danny

Olson SJ CED/IRW, Charis SJ CED/MAD, Charis SJ ENG/IRW, Lowden O25c, Ayers MICCR
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