My aim was to finish the fit of the seat and chain stay tubes, check the lengths and alignment and then tack it all up and fit a rear wheel to make sure everything clears.
Before tacking the rear end up I needed to fabricate brass ring inserts to go into the stays at the drop-out ends. The reason frame builders do this is to ensure sufficient brass is present in the joint. Normal 'tube to tube' joints don't require this because they have a close fit all the way around whereas the dropout joint has a big gap in it where the flat plate dropout slides into the round tube - see pic below:
To make these little brass rings I just used the bits of brazing rod which had become too short to use for normal joints and wrapped them around a round file which just happened to the about the correct diameter!
Next up it was time to take the plunge and fit a rear wheel to make sure it cleared and sat in the middle of the frame. As you can see below the wheel fitted ok and cleared easily. I think a bit of 'tweaking' will be required to get the wheel to sit in the middle of the frame - but as far as I can gather this is par for the course with handmade frames!
When desinging the frame I accounted for anything up to a 2.4" tyre, in hindsight its unlikely that I will use such a large carcass tyre and so I could have got away with being a bit racier on the chainstay length and generally tucked the wheel in closer to the seatube - a development for frame number two perhaps?
The original aim was to get the frame to be sub 2kg, however when I guesstimated the frame weight during the design phase I found it hard to get an idea of exactly how much the fillet brazed joints would add to the overall frame weight. The answer is a lot!! I have intentionally ensured that each braze has nice large radii and so they are possibly a little over engineered for the application.
Including the sliding aluminium drop-outs the frame currently weighs 2.3kg, however I am yet to fettle the headtube joint so this might come down a bit. This is a bit disappointing but looking at competitor frames (Niner Sir 9, Singular Swift etc etc) its about par for the course.
Next up I need to tweak the left rear seatstay and then fully braze up the rear end. Following that I need to get a seatstay bridge bent up and get that fitted then its just the odds and ends of cable and bottle mounts and it should be ready for painting!!
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