Who might possibly have made a no-hole arched-top to flathead conversion ring that was flat on the under side like an arched top ring?
I think I've read the FQMS conversion ring was like that.
That's what I kinda thought FQMS.......It has not been lathed out on the bottom side......
Not sure about the no hole, but I've got a couple of 20 holes that was not cut under...
Our original arch to flat conversion rings were exactly how you are describing what you have. Upside down on a table, they are identical looking with the pre war Gibson archtop ring.
Our new conversion ring has a small bit of machining done to the underside to bring it inline with the weight of our V35 ring which weighs in at 51oz. The contact area of the ring with the top of the rim is just like our flathead rings. And still no holes. Hope this helps.
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