By James Morikawa
I weld and braze the mitered frame-parts starting at the rear-triangle. I quess I can say, "I build from the rear — forward".
First weld joint will be the seat-tube, bottom-bracket joint.
I tack weld his joint with frame parts mounted on the frame-jig.
I don't do the full-weld on the frame-jig.
Once tack-welded, I remove the seat-tube/bottom-bracket from the frame-jig. I mount it on my welding fixture, and complete the weld.
After I complete this weld-joint I check for alignment. The bottom-bracket has to be 90 degree squared with the seat-tube — very important to the future alignment of the completed frame. It will be impossible to correct any mis-alignment here on a fully welded frame — without effecting the alignment of other frame sections. If it's not 90 degree-squared, I need align it on my Henry James Alignment System. I don't move on to welding the chain-stays unless it's aligned.
I remount the seat-tube/bottom-bracket on the frame-jig; mount the chainstays, and tack-weld the stays.
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After tack-welding, I finish off the welding on my welding fixture.
Above, I'm welding the chain-stays. The welding fixture allows me to position the weld-areas for good "weld positioning". There is clear floor space underneath the weld-area for ease of moving around on my welding-chair — which rolls on casters along with the foot-control-pedal.
Anyway, the completed chainstay welds.
OK, I now remount things back onto the frame-jig — with drop-outs in place.
I silver-braze the drop-outs.
I always check for alignment. That's before, and after brazing the drop-outs. If there's any misalignment in the chain-stays I need to correct them at this point.
The welded frame-parts should easily remount back into the frame-jig — without any forcing. The idea is to get each section that's being welding or brazed into alignment before moving on. I do a lot of checking, and re-checking though-out the build.
I don't want to build a mis-alignment into a completed frame. There are all sorts of frame mis-alignments that can be built into a frame — where one attempts to "cold set correct" a mis-alignment only to end up with another type of mis-alignment.
Build it straight as you go.
That's it for this webpage. Have a blessed day.