Paul Brodie has been taking us through, over the last week, the steps involved with recreating an 1888 full suspension Whippet bicycle. Paul is a master framebuilder who has been part of the Canadian MTB scene since 1985.
“I call this part of the Whippet the Scissor Linkage. The linkage should not be fully extended, as in the photo below. When working properly, it’s more like a fish mouth viewed from the side, opening and closing. This bike has been through some abuse, and some part of the frame is either stretched, or bent. This linkage is from an early Whippet, as later models hinged on ball bearings.
I’ve taken some 5/8″ flat cold rolled steel, marked out the shape, rough cut it in the bandsaw, drilled two holes, and now the ends are having a smooth radius cut with an endmill. The holder is mounted in a three-jaw chuck, on top of the rotary table”:
“The ends are now smooth, I’ve drilled three holes and marked material to be removed with a red pen. The piece of cardboard is my template — all I’m working from. No fancy Autocad drawings to get this bike done! Next step is to carefully use the vertical bandsaw to remove the metal between the lines”:
“Each linkage piece is now put back in the mill vise and a 1/4″ endmill used to finish the slot. It needs to be quite precise as the two linkage pieces have to fit together exactly”:
“A larger endmill is used to shape the other end. Note the feeler gauge being used with another small piece of steel (not seen), to prevent the end from being ‘squeezed’. This allows the vise to hold the linkage securely. When making parts, the first thought is always ‘How am I going to hold this?'”
“This is the finished Scissor Linkage after a bit of filing and polishing. It will get bead blasted and sent out for Electroless Nickel plating, which is a very nice finish. I hope you have enjoyed this installment of how things get made in my shop!”
Paul teaches Framebuilding 101 at the University of the Fraser Valley. For more information on the course, where you can learn how to build a steel framed bicycle using Paul’s original jigs that have built over 4000 frames, visit the UFV website.