I have never seen a Sachs' bike, and going by photos hasn't helped much due to the vast majority being of his more recent work and those pictures that were of earlier designs were poor in showing any details. Seeing only a couple of poor photographic examples of that same style fork crown has not allowed me to do an accurate comparison. The tangs were a match to other examples. I will say that all of the brazing is very clean and the lug points are VERY sharp (even with 2 coats of paint). The "RS" in the crown is very well defined, and yes, deep considering the paint. I assume I'll see Columbus stamps on the tubes once stripped. The repaint was of decent quality so someone had been trying to take care of this frame set. When I get the frame in hand I'm sure more will come to light. I'd message Mr. Sachs and ask if he ever used Simplex dropouts, but I think I'd like to see the work on the frame first before wasting his time; I'd also ask when he started and stopped using the "RS" crown design. I think "Worthy" is correct in that the frame is of 70's European stock, and since neither French or Italian BB threading, it dwindles down the options a fair amount. Most of the components were 70's: Campy Gran/Nuovo Gran Sport, with a full Sugino crankset, and SR post and stem; early Super Champion rims. The newer (80's) stuff was Sun Tour clamp-on DT shift levers and skewers, Shimano hubs, and Nitto bars. Really no poor components; I figure that it was shop outfitted as a complete ride when new with most of the existing components typical of a European entry level bike. Of course when and why the fork was changed is a mystery for the ages. I have notes that have me buying the bike primarily due to the fork and the parts, so the frame itself did not make an impression at the time. I paid $140 which I thought a bit high for my normal mystery buys. He was asking $325 originally, but since he really didn't know what he had and neither did I; I offered less than 50% (150) to get an idea, he wanted 200, so dropped the Brooks Cambria saddle and left at 140 which might be the value of the fork alone now that it has been ID'd. Although the mystery is not solved, I don't feel bad about the buy, and as usual I learned a lot with the help and knowledge of the FORUM community. THANKS!