Inside Frank’s Cranks, part 1

bluecrank3
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Frank Ford –

I’ve been making these string winders for a few years now, and here at the shop they’ve been a point of conversation over their various features and styles.  Once folks find out that I actually do all the operations myself, the most popular question is, “How do you make the eighty-three degree angle on the handle?”

So, just for fun, I thought I’d post some photos of the process.

After I drill the 1/2″ brass ball to accept the 1/4″ diameter aluminum crank arm, I apply a small drop of a special Loctite retaining compound.  This anaerobic adhesive is catalyzed in the presence of metal, and in this application, achieves about the same strength as an interference, or press-fit:

crankarm01

And I insert the rod into the hole, where the green compound will lock it permanently in place within a few seconds:

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Then it’s over to my tiny Rusnok milling machine to drill the ball for that 83-degree handle bearing.  In order to achieve repetitive alignment, I’ve milled a pair of “soft jaws” in the mill vise to hold the rod and ball assembly with rigidity and precision in a cavity that exactly matches its profile:

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pearlyellow

New for 2018 – Matched Sets of Acrylic Handle Cranks!

 

Then, a vertical drilling operation gives me that angle automatically:

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Another drop of that magic green fluid secures the 3/16″ diameter steel bearing:

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Here’s a cutaway view of the final assembly – note that the smaller rod is drilled through both the ball and the larger rod, making the joint incredibly solid and secure:

crankarm12

 

Once the arm is assembled, I can hold it in my special little fixture that keeps it aligned while I whack it with a steel stamp:

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None genuine without this brand:

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koacrank

New for 2018 – Figured Koa Handle Cranks!

 

 

Coming soon – Part 2 – The Crank Handle Bearing



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