There is no doubt that Jackson as well as others suffered from the effects of high demand and trying to meet those demands during the bike boom. One of the problems with Jackson, as I understand it, was that Bob sold the business and the quality went downhill from there. He later acquired the business back and brought new life and the quality back into the frames that bared his name.
In 1978 I bought a Guerciotti from a friend who owned Georgetown Cycle and Sport in the DC area. The water bottle bosses on the downtube were not centered and there was a problem getting the chain line where it should be. I just about went crazy trying to figure out the chain line problem on this bike. Then one day while riding and looking down at the chain rings and bottom bracket I noticed that the bottom bracket wasnt square to the top tube. After measuring from the dropouts and fork ends to the bottom bracket I discovered that the BB was about an 1/8 of an inch or so off. I talked to Danny, the owner of the shop and he told me to come in and pick out another frame. In looking at another Guerciotti I decided the quality wasnt there and picked out Serotta. While assembling that frame I happened to notice that one of the fork tips was brazed in a more forward position that the other one.I called Danny and told him about this and told me he would give me my money back. We had a discussion about the quality of many frames dropping as builders were trying to meet the demand during the bike boom. Schwinn had quality problems with the Paramount in the early 70s, about the time they quit using Nervex Pro lugs on the bottom bracket.
It might be interesting to hear from list members their tails of grossly assembeled and brazed frames.
Mark, day off + good weather = long ride, Poore