front threads on Dagor lens

Hi.
I recently purchased a 12" Dagor lens, which has front threads that are almost 58 mm, making it impossible to find appropriate accessories.
Does anyone know how I can adapt this for 58mm; either by purchasing an adapter, or by having the lens re-machined?
Thanks,
Steven

Hmm. If all else fails, ask skgrimes about making a push-on adapter that will accept a standard-sized filter. Machining the lens should probably be a last resort.

Dagor Front threads

Steve,

I have the exact lens. Older lens typically do not have modern day accessory thread sizes. My lens has plastic lens caps with the number 60 imprinted on the cap. No doubt because the outside dimension of the front element is 60mm, the inside dimenision meauseres 56mm. You can only hope to find a 60mm compression slip on filter holder, again not commonly found.
For what it's worth, all my filters are series 9 with various step down rings for various lens I have. With a series 9 filter holder and a step down ring you can just carefully place on the front element so long as the camera is not tilted downward. Good luck

Would it have inch size threads? 58mm is awful close to 2.25 inches....

Best solution I have found is a Cokin filter holder with an adapter with pinch screws instead of a threaded ring.