No. 9 aerial base
 

It seems there are 2 types of No. 9 base that were produced. The only difference being the diameter of tube that was used for the "stem" and the position of the weld, on top of the plate or the bottom. The two examples I have pictured on the left are made from schedule 80, 1 1/4" pipe, giving a diameter of 1.670". The other 2 examples (the two on the right in the right hand photo) are made from 1 3/4" tubing, giving (obviously) an outside dia. of 1.750". There must have been 2 different cages made to suit the two different diameter stems. I have tried a cage on the smaller dia. bases, and it will not tighten on. So it must be for the larger style base. Any input on which base is more prevalent? I am about to finish a run of repo's, and would like to make the more "popular" base, as I will be making cages as well.

thanks, Perry

All my originals have been from 1 1/4" nominal bore measuring 1.67" dia. with the weld on top as your centre example.

Thanks Adrian. I am not sure which of the designs are more plentiful.
Anyone else?

Hello Perry
If I remember correctly the bases I have/had came from UK, USA and Netherlands.
The Bird Cage came from Holland. Difference should be minimal, wouldn't you just pry it open a little bit and use a longer bolt?

Geoff

Geoff,
The cage I did have would tighten on the larger diameter bases, but even with the flanges pulled together, would still not tighten on the smaller diameter bases.

Perry