Hello everyone and good day!
As a side project i've been doing some research on the odd, early Hampden model 2's with hollow center pinions. So far i have been able to identify 3 grades. Railway, J.C. Perry, and Theo E. Studley.
Ill do my best to explain them, and ask if anyone has any of these, or pictures, i would love information for research. Trying to figure out just how many there may be, and if there are any additional grades, is ultimately the goal if at all possible. The hampden blue book has many numbers in and around the references ill show you, but theres no way to know unless some examples turn up!
In the pictures below are the two i have managed to collect so far.
J.C. Perry #75257 15 jewels adjusted coarse train (16,200 bph)
Theo E. Studley #100647 11 jewels coarse train
Some points about these movements, they are distinguishable from the typical model 2's because they have a male winding stem and large swing out setting lever as shown in the picture below. On the top plate you will notice the full signature of the grade name instead of the typical Hampden labeling (unless its a private label). Example being Theo E. Studley and J.C. Perry instead of just Studley and Perry. One can also notice the giant center pinion from the view of the top plate. Side note, that dial in the picture is very wrong and the correct dial should have a block letter signature. I've noted a few with private labels now, making the distinction between railway and J.C.Perry grades difficult. The railway has been found to be quick train (18,000bph) and have gold jewel settings. J.C.Perry is coarse train and does not have gold jewel settings.
On top of my two, there are two that can be viewed on page 17 of the Hampden blue book
75344 nickel 15 jewels adjusted private label. J.C.Perry or Railway grade i think its a railway from the brightness of jewel setting
100609 gilt 11 jewel private label Theo E. Studley grade
Also in the blue book on page 17, there is a diagram of the hollow center pinions, and i included a picture below of it taken apart.
i have 4 more noted in addition to the 4 above.
two in the 75xxx range one a Railway and one a private label Railway
two in the 100,xxx range both Theo E Studley, one is a private label
Im hoping by posting this here i will be able to uncover some more pictures and serial numbers, who knows maybe even a new grade. i keep waiting for a Chester Woolworth to pop up, but i have no proof it exists. i Have a feeling that sn 100,000-100,100 could be where they are hiding.
If you have any information, or examples, or anything at all please send a post! Thank you very much and have a good day!