I recently bought a guitar body and tried to bit my Callaham bridge and because the route for the trem block is slightly off-centre it doesnt fit. If aligned centrally the block catched on the top edge of the block route.
Now the Callaham block is a few mm wider than a standard fender, which does 'just' fit, but if the bridge is aligned with the centre-line of the body there is about 1mm clearance at the top and 3-4mm at the bottom, so to me, the lock route is out of alignment.
The measurements should be as follows according to a Fender blueprint, and if they were the Callaham block would fit.
Bottom to centre 1.75"
The manufacturer of the body is stating "Our body is taken from an actual original, most people want a copy of an original." and not taking my argument on board which is:
The Callaham trem WILL fit a vintage correct route if it is sized/aligned correctly
The Fender trem sits off-centre in your route, it shouldn't, it should have equal clearance both sides. It does 'fit' but only just
The reasons for this is 1960's manufacturing tolerances. The body you are copying is not quite right
With CNC you should be able to make a '60's body as-per design, not just take a copy of one that want quite right to begin with
Thoughts?
Comments
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein
Basically the question is what is 'correct' as per the plan, or as-per one particular 1960's body?
My dad was a metrologist (measurement science engineer) and drummed this into me, for what it's worth!
OK, a Strat body is not exactly precision engineering... but since one of the major unknowns is the hand-sanding of the body edges, there's no guarantee that the centreline of the finished body quite matches the centreline of the machined routing any more.
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein
Another consideration is how the unfinished wood as been treated after the shaping. Moisture content variations can play havoc. Wood can warp.
Bottom line. You can always cut more wood away. You cannot easily put it back.
You can also think like a designer and infer the intended nominal size from the measured size. it's relatively rare that something is designed with grotty nominal numbers, although they can exist as a result of geometry (like the length of one side of a triangle is nearly always grotty to multiple decimal places).
The Strat blueprint is quite interesting in that the main shape is defined in fractional inches while details like cavities are in decimal inches. The default tolerance for the fractions is +/- 1/32" (0.79375mm), but +/- 0.010" and +/- 0.005" for 2 and 3-place decimals (0.254mm and 0.127mm). So, they allow for more slop in the body outline than in the cavities. Also interesting is the rather odd size of the radius at the left-most side of the control cavity - 0.438". It's actually a rounding of 0.4375", which is exactly 7/16", indicating that the cavities were still conceived (at least in part) in fractional terms, and converted to decimal to apply the tighter default tolerances.
It's notable that the curves of the body (horns, bouts, waist) are undefined apart from some convex extremities - there are no radii, the positions of the concave extremities have no dimensions, and the distances of the extremities of the horns from the centre line are undefined. Probably hand drawn or traced and intended to be transferred onto a template directly - there's a note at bottom-left which says "[illegible] of body may be taken from dwg".
Nomad
Nobody loves me but my mother... and she could be jivin' too...
"Perimeter", I think.
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein
Yes, I'd probably draw lines from the ends of the neck and bridge cavities and find the mid-point (they're good to within 5 thou). If they're all parallel, and if the derived centre line results in the bridge being better placed in the cavity, that would be a good sign. I'd be tempted to then fit the neck and see how that all matches up as well.
Aye, that's it.Nomad
Nobody loves me but my mother... and she could be jivin' too...
Because at the end of the day, it's the alignment of the bridge to the neck that really matters, nothing else. The only other thing of any real importance is whether the pickup polepieces line up with the strings, and there will be a little leeway in the position of the pickguard to achieve that.
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein
The next pic shows the block in position
You can see the problem seems to be that the trem block route in the body is of-centre, as-per the original '60's body
My argument is this is wrong and should have been corrected, the manufacturer argues that it's 'vintage correct' and this is how people want them
I didn't realise the pivot screw holes were pre-drilled. If they're in the right place relative to the neck, you definitely don't want to plug and redrill them - even if that was really a good idea at all. The only sensible solution here is to enlarge the end of the cavity by just enough that the block clears it. The problem then may be that the cavity is slightly visible at the arm end, which it shouldn't be.
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein
I agree that if the original is like this it's wrong too, however the manufacturer won't move from the position of 'that's how people want them, and exact copy of an original'
They are charging me to enlarge the route because of my 'non-standard part'
As I said, a genuine Fender blockwill just about squeezes in there but its clearly off-centre, here it is with a Fender block
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein
Just actually got the body back from them, they charged me £35 to "adjust the trem route to accommodate a non-standard trem" To be fair they made a very good job of it, and strangely enough I've had the calipers on there and the trem route is within a hair of the 3.125" it should be according to the blueprint
In addition to the swampy body issue, i had another body from them where the neck pocket was 2mm too deep... http://a67.tinypic.com/21mx7xt.jpg
end of the board should have a gap under it!... USA neck!...