Thanks for all the answers.
Having no certainty as to whether the frame is fine, I'm trying to be economical in the build. Winston checked it, confirmed structural integrity as far as visual inspection allows and re tracked it the best he could without access to appropriate jig (a long one for tandem frames). He suggested I build the bike and see how it feels, then it may need further fine tuning, but probably not... The good old Sheldon Brown technique of running a string between head tube and rear dropouts, that I had a go at when getting the frame back, shows near perfect seat tubes alignment (as far as I could tell, half a millimeter out for the front seat tube, pretty much perfect for the stocker's) and the rear triangle is good as well (Winston mostly had to work on rear triangle and fork, not so much on the bigger tubes parts).
So, as I gather parts I'm trying to use as much from my spares as I can. I have a 1980s / 1990s front wheel, in very good nick, hardly any of the grey finish on Mavic rim braking surface is gone, Shimano 600 hub, stainless steel spokes, 36 of them... I was hoping to use it so I only have to build a rear wheel.
I'll do that for now...
Thanks for all the answers.
Having no certainty as to whether the frame is fine, I'm trying to be economical in the build. Winston checked it, confirmed structural integrity as far as visual inspection allows and re tracked it the best he could without access to appropriate jig (a long one for tandem frames). He suggested I build the bike and see how it feels, then it may need further fine tuning, but probably not... The good old Sheldon Brown technique of running a string between head tube and rear dropouts, that I had a go at when getting the frame back, shows near perfect seat tubes alignment (as far as I could tell, half a millimeter out for the front seat tube, pretty much perfect for the stocker's) and the rear triangle is good as well (Winston mostly had to work on rear triangle and fork, not so much on the bigger tubes parts).
So, as I gather parts I'm trying to use as much from my spares as I can. I have a 1980s / 1990s front wheel, in very good nick, hardly any of the grey finish on Mavic rim braking surface is gone, Shimano 600 hub, stainless steel spokes, 36 of them... I was hoping to use it so I only have to build a rear wheel.
I'll do that for now...