Prater’s Theory seems feasible for the great pyramid’s casing stones supporting a ramp that spirals up to the very top of the pyramid and for utilising a spiral ramp on the internal structure.

7.5 – degree Ramps

The blocks in the great pyramid should be getting lighter at this height. A 7.5-degree ramp could continue from the 2-degree ramp, finishing within 5 meters from the top of the pyramid, sitting on the internal structure. This gradient can also be used from ground level, spiraling up on the outside casings to the very top.

The ramp could be supported by stone protrusions. These are casing stones which jut out, at intervals, under the ramp and later cut back flush to the face of the pyramid. The protrusions wouldn’t carry all the weight of the ramp. Some of that weight would be carried by the pyramid’s sloping walls and more so at the corners. The casings stones continually under the ramp would be better, ensuring stability. An image of the protrusions can be found on Images Relative to Pages.

If the 7.5-degree ramp was supported on the outside by the casing stones, the ramp would finish above the last casing stones placed. Perfect for the cap.

In the image above, the casing stones are 2 meters in width, all fitting under the rigs, passing through onto the next section of the spiral ramp.

There is room for the men to go on either side of the rollers, but men could also go underneath the ramp, working in the shade. Luxury! Having the builders underneath the ramp and using the spool’s smaller circumference would require fewer builders, which suits having less room below.

In creating the image, I calculated the number of men required underneath the ramp, the distance the spool travelled, and the weight moved, like I do in all my images. I can not remember, offhand, the size of blocks I calculated for, but it all worked out, and I know something, with these large spools, I was not calculating for small blocks. Because, based on testing the set-up, in the garden, with a very small spool, moving a 15-tonne casing stone up the pyramid would only take 28 men. These figures should be less because it was so easy moving 0.544-tonnes up the 7.5-degree ramp.