Vintage Windmill and Wind Generator Forum

The ID of the 8' 12A turntable is just shy of 2.5". I believe the diameter of the 12A mast pipe is larger than 2".

2 inch pipe would have an OD of around 2 1/4 give or take.

pipe is measured ID, and tubing is measured OD. Took me about 60 years to learn that. lol

I picked up a 2" piece of tubing at the local scrap yard , drilled a hole for the clamp to fit into , perfect in the clamp at the base of the Dempster motor , early #12

The hole in the top bearing race for a 10 ft Dempater is 2 1/2 inches part number is 1155. I'll need to look if I have a second one as the one I do have is taken. I'm not sure about the top casting that mounts on the legs that the bottom bearing race sets in.

Wayne wrote: ↑Tue Nov 28, 2023 9:57 am The hole in the top bearing race for a 10 ft Dempater is 2 1/2 inches part number is 1155. I'll need to look if I have a second one as the one I do have is taken. I'm not sure about the top casting that mounts on the legs that the bottom bearing race sets in.

The PN of the 12A top bearing race is also 1155.

Have been following this thread, it has been of interest.

Getting back to the very first photograph in the first post on page one; the one showing the top part of the tower. What is of special interest to me is the tower cap. Have noticed 2 small two holes in the side of the tower cap that was facing the camera, one in the middle of that side, and one beside it. Curious as to what their purpose was.

Many moons ago, I was dismantling a Dempster No. 9, and the associated tower, in Missouri. Almost certain it was a Dempster tower. Had a tower cap very much identical to the one in the above mentioned photo. This tower cap had similar small holes in it. One such hole was in the middle of one side, another was in the opposite side. Th other two sides had no such holes. There was no small hole beside the ones in the middle of the sides as in the above tower cap.

Have been of the opinion that the two holes in the tower cap of the Missouri mill were done in the field. You will notice in the above mentioned photo how the corner posts overlap in the tower cap. The tower in Missouri had the same overlap. The holes in the cap, in mine at least, went on through the overlapping angles, and a bolt went through it all. Maybe someone thought extra bolts were needed. On one side this more or less worked, but on the other side the hole in one of the angles stayed inside the angle, but not so with the other angle. The drill bit broke through the edge of the angle, leaving a hole of sorts, but with a "nick" or a "break" in it.

I wonder what fellow vintage windmillers would have to say or post about this.

Challenge 27

P.S. Dare say many vintage windmillers have had the sentiment, as I have often had ... "if only these old parts could talk!"

I have 4 of the 10 ft top bearing races and all are part num 1155. My 8 ft are the last number Dempster used 380-3-0069.

in case you didn't know, the 4 digit numbers are the old part number. The long nnumber is the new style part numbers. If I have my Dempster catalog, I could look up the parts to see if they used the same tower top casting for both mills. I'm thinking they did, but not positive.

The ten ft 12 and the eight foot 12a use the same turntable. The 8 ft number 12 is smaller