It will reduce the potential for rounding errors and confusion if we stick to decimals for calculations and only convert to fraction equivalents for the final figures.
The alignment fixture drawing shows that the inner engine mounting holes as 7.593 x2 =15.186 = 15+3/16" apart. The outer mount holes are a further 3.375 out on each side so this makes them 21+15/16" apart. This should make the centres of the engine mount tower 18+9/16" apart and this being the distance between the centres of the legs…
Below, numbers in bold are read directly from the alignment drawing.
A simpler way of calculating the distance between the lateral centres of the mounting tower bases is to take the distance from the lateral centreline to the centre of the inner tower mounting bolt hole = 7.593, double it to get the lateral distance between the inner bolts = 15.186 (as you have done = dimension U) then add to that 2x half (=1x) the lateral distance between the inner and outer tower mounting bolts 3.375. This gives us 18.561, or 18+9/16 for the chassis rail centrelines. So we agree.
…but I do wonder if this is meant to be 18+5/8"?
Explanation needed, please.
The legs being 2+5/8" wide each
I haven’t seen a width dimension for the chassis legs in factory documentation. I measured my Traveller which has its original legs in excellent condition. Measured with callipers they are 2.6” or near enough to 2+5/8. So we agree.
…this makes the "N" the distance between the insides of the chassis legs as 15+15/16" or more likely 16” if my above theory is right?
It seems that your derivation of 15+15/16” is the lateral separation of the chassis centrelines minus 2x half the one chassis rail width (= 1x2.6 as above). The value we want is 18.561-2.6 = 15.961 or 15+31/32. Close enough to your value, so we agree.
The Chassis Alignment fixture positions the legs apart on their inside faces 7.937 x 2 =15+7/8"
I agree that the tube on the jig that runs transversely between the eyebolt holes gives a strong indication of the leg spacing. As you say, it is 2x7.937 = 15.874 or 15+7/8. So we agree.
I have read elsewhere that perhaps there should be a fitting clearance added here of 1/16" each side which would again make the legs 16" apart.
I’m not completely convinced. The jig’s transverse tube between the eyebolt holes has a solid metal plug at one end that has a small recess which I assume is to accommodate any slight protrusion from the chassis leg of the sleeve that houses the eyebolt. So it seems that it is meant to be mounted flush against the leg. At the other end of the tube is a loose disk 3/4” wide that also has a chamfer or recess adjacent to the leg that may be to clear the end eyebolt sleeve. The purpose of the loose piece in the design would seem to be to obviate the need for significant extra clearance.
So I ask if you think that the 16+1/8" you have for "N" is correct.
I now think that anywhere between 15+7/8 and 16 at the eyebolt hole would be acceptable.
Also you have for "O" the torsion bar centres as 22+44/64" - that should be 22+11/16"
“44/64” oops! I did a most of this in front of a television. That’s my excuse.
…but 58.1cm = 22+7/8" as near as dam it by the way but my reproduction crossmember measures 22+13/16".
Yes, the measurements should be 22+7/8” (or 22.875”) and 58.1cm.
Thanks for your input. I'll have to update my table and diagram now.
Bodywork dimensions
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Re: Bodywork dimensions
Here is an updated diagram, table and notes with corrections as discussed above.
Thanks to Nourish (Martin) for his feedback.
Notes to follow...
Thanks to Nourish (Martin) for his feedback.
Notes to follow...
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Re: Bodywork dimensions
Notes to the above diagram and table:
I would like to add the measurement of the longitudinal separation of the damper mounting surface to the centreline of the eyebolts. I haven't been able to make an accurate mention on my own Minors at this stage.
Are there any other dimensions that others would like to see added?
I hope this information proves to be helpful to those undertaking Minor restorations.
Comment/corrections welcome.
Don
I would like to add the measurement of the longitudinal separation of the damper mounting surface to the centreline of the eyebolts. I haven't been able to make an accurate mention on my own Minors at this stage.
Are there any other dimensions that others would like to see added?
I hope this information proves to be helpful to those undertaking Minor restorations.
Comment/corrections welcome.
Don
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Re: Bodywork dimensions
Clearly, my brain had slipped out of gear when I wrote this. That measurement is in the table.I would like to add the measurement of the longitudinal separation of the damper mounting surface to the centreline of the eyebolts. I haven't been able to make an accurate mention on my own Minors at this stage.
Don
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