Cheers Dave
The Boss was has been away all day visiting an old school friend, so I was in pigs heaven, all day in the shop.
First bit the crank shaft, turn up and thread the end and cut off
Next bits the crank webs, made from 1/2"*1/4" mild steel bar cut off a couple of bits allowing a bit for cleaning up, then mark out
Then drill both 8mm
Then stick a bit of 8mm bar through both bits and then drill 6mm hole this way the hole centres will be exactly the same for both bits.
Then turn up a 8mm mandrell
Mount both bits to the mandrel tighten up tight abd skim down the ends to form a nice rad
Turn the mandrell down to 6mm mount the bits back onto it and turn the other end down.
Give both parts a tidy up and a polish
Then with high strength loctite assemble the crank shaft and cronk pin.
Just to make sure drill and pin the webs in place.
For the pins use nails cut off just a little longer than required and rivet in place and clean up, and cut out the middle bit of the crank shaft.
Next bit the eccentric to avoid the use of a milling machine this is fabricated in two part plus the eccentric sheath.
Luckily I had a bit of brass tube that was near to dam it the corect size all I had to do was part a ring off, and drill and tap M3 for the shaft.
The eccentric first part was a top hat outer part.
Then the inner part this as the off set for the throw.
Turn up dia for assembly to the top hat bit
Try the fit
Flip it round in the chuck face to thickness and put in a small centre.
Then mark out the throw.
Set it up with a wobble bar
Drill and ream
Turn up the boss
And stick the bits together with high strength loctite
And a try for fit of todays bits.
Stew