I don't think we can come up with solid dates unless we find multiple original pedal owners with dated receipts.

I can tell you what is found in print and slim it down a bit. The patent for it was filed May 1960. The dial was used at first, as you mentioned, and could still be seen in the 1964R catalog in the picture. 64R catalog stayed in print for 1965- just with a price updated mailer. The next photo shoot was the 67/68 CBS catalog. It has the wing screw shown.

Was it a 1966 CBS change? Did they simply use the newer wing design in around 1965/66 when they ran out of the older design round knob? Were they using an older picture in the catalogs? I don't know.

Thanks Gary N for the approximate dating on the change from knob to wing bolt on the pedal clamp. Any idea when the hinging of the foot board heel changed?

Well, if the change from knob to wing bolt was about 65/66, we know the change in heel plates had to be after that because both heel plate versions had the wing bolt....

[Attachment: 98163] [Attachment: 98164] [Attachment: 98165]

Change had to occur during the Dayton era, but I also would like to hear from original Dayton owners who could verify.

Mike

Nice advert photo Mike. That's a keeper. I note in the catalog cuts you can see on vintagedrumguide, that the pedals in the 67/68 catalog have the earlier heel, and by the 1970 catalog, it looks as if the heel has changed. So maybe it was an early Fullerton development - 69-ish???

My first Swiv•o•matic pedal had a hinged Patent Pend footboard and the T-screw.

The illustration on the box had the round screw.

I traded my Rogers Rocket even for it in 1969 from a local country drummer who bought it new, used it a few times but didn't like it because he said it was too complicated. He put it back in the box and it sat there until I came along. I never asked him when he bought it.