It's been a difficult day so far..and it became even worse when I saw Wayne's contri about Dave Bohm's reworking of the RGF bottom bracket shell and the Bocama lugs. In retrospect perhaps I am over reacting..it's just that the contri caused me to revew much of the work I have done on bike frames for nigh on 50 years and to revisit some of the principles on which my working procedures have been based.
Like many frame-builders I have always been more than happy to use RGF cast bracket shells because they are accurately made, the castings are sound, the threads are usually well-formed,and they contribute to a stiff and responsive frame. I have never known one to ovalise in use or to crack or deform in any way, being ultimately very dependable and suited to the purpose for which they were made. They were often the first sign of a quality frame made by a builder who knew his materials. I have never thought that they were "rough", just in need of a little cleaning and smoothing, but far far better than the cast brackets of the 50s. in all respects.
Similarly Bocama lugs were always robust, well thought out for the purpose in hand, but did require some refinement in terms of filing down and profiling...but never anything drastic.
The purpose of this email is not in any way to criticise Dave Bohm's skills because he clearly has immense talent with his jeweller's saw and needle files, but instead I wish to ask quite simply "Why?" Why take that bracket shell and lugs and then set about wholesale alterations, alterations that although rendering the components more artistic, might in fact lead to them being weaker than they were at the outset thereby jeopardising possibly the integrity of the construction and the ride quality of the finished frame? Would it not have been more sensible to take a blank one or if none were available, to weld one up, and then cut the profiles.
Most Bocama lugs arrive with a ring of metal attached to the headlugs, in the same way that Nervex Pros did That ring has a function - to help to prevent the ovalisation of the head bearing sockets, thereby reducing or removing judder. Dave appears to have removed those rings. If they appear slightly ugly, it is always possible to run a bead of weld material along them and then file them into an elegant concave curve that not only enhances their appearance but strengthens the headlugs against ovalisation even further.
The removal of the outer tube socket walls on the bracket shell and their replacment with longer tangs seems not a bad idea, but if those tangs are only brazed or bronze-welded into place rather than fusion welded thereby producing at least a semblance of homogeneity and structural integrity, it does bring into question whether the end result was worth all the effort. My own experience suggests that such tangs as these and those brazed to the lugs are little better than window-dressing.."ars gratia artis". Presumably Dave will use silver-solder when he eventually "brazes" the frame together, otherwise there would be a risk of the added-on tangs, floating off under the torch. Should the frame be chrome-plated there would also be a risk of the acid etching slightly into the tangs' b/o joints, and of under-cutting the filed and dressed weld.
I came across this contri about two hours after I had put to one side the Bernard Carre-built Sauvage -Lejeune frame that I had been cleaning up. This is the 1965 frame that carried Henri Anglade to the French Champion's jersey and to 4th on GC in that year's Tour, together with a number of high placings in top-ranking races.
Coincidentally this frame has an RGF bracket shell, but neither the shell nor any of the Prugnat short-point lugs have had any reworking nor, I suspect ,even the stroke of a file gently across their surfaces. The front and rear drop-outs and their joints into the blades and stays are just as the torch left them.
Membership of the List and the privilege of being able to read all the contris has made me very much aware of the vast gulf that exists between perceptions of a custom frame in the States and those held in the UK. Clearly the clientelle for custom frames over there demands and is willing to pay for far more "art" than a British builder could ever hope to find stepping through his workshop door. Perhaps that is the difference..American builders have studios and British ones have workshops...I suppose, on reflection I am firmly rooted in the "form follows function.." school of framebuilding.
Norris Lockley, Settle UK