wanted: Chev CMP chassis views

[Eduard Sorokin]

Originally Posted by Hanno Spoelstra

Niels was so kind to measure up the chassis of his CGT and C30 trucks - please refer to the attached drawing from the Chevrolet manual to which I added red lines at datum points "C", "D", "E" and "F".

He reported the following frame height dimensions on the outside of the C30 frame rail:
C: 20 cm
D: 20,5 cm
E: 18 cm
F: 14,5 cm
On the CGT it was bit hard to get the measurements, but from what Niels could tell they where the same as on the C30.

Well, one more enigma is here.
I always thought, all images in technical manuals, handbooks and spare parts catalogues have the factory blueprints as their base. And looking on CMP frame drawing in Manual, I was glad, because of this drawing could to be very useful (for example, in scale modelling of any CMP truck).

Now dear Hanno and Niels provided us with exact dimensions of frame side member heights.
Having those dimensions, I tried to measure those heights on that image from Manual to compare them. Using rear spring length (49 1/2 in.) as basic dimension, I have found the scale of Manual drawing and measured and calculated the remaining dimensions.

My results are below:
C: 15,03 cm,
D: 14,4 cm,
E: 13,28 cm,
F: 10,28 cm.

Thus, the results are very different from the actual dimensions. And my conclusions are:

1) The Manual's authors used some random "drawing" (based of factory plans of frame), which is similar to all frames of all CMP models (for the purpose not to give different drawing each time, in each Manual on each other model). The author's intention was to give general view (overall arrangement) of CMP frame, without too many particular detailing.

2) Possibly, the authors used frame drawing from lighter models - from C15 or even from C8. Only measuring of frames of those exact models could to confirm or to refute this assumption.

3) Finally, the Manual authors could made simple sketch drawing of frame - "by eye", and without use of any factory drawing, to show only general shape of frame.

This is big, big enigma...

[Harry Moon]

!6 inch CMP wheels don't fit on the big front axle with the large brakes. tried, don't fit?

[Hanno Spoelstra]

Originally Posted by Harry Moon

16 inch CMP wheels don't fit on the big front axle with the large brakes. tried, don't fit?

Thank for the input, Harry. Have not tried to fit them myself, but others told me the 16" rims fit on 15" diameter brake drums.
Also, C15A, C30 have 16" rims on 15" diameter rear drum brakes, right?