Facing Chainring Spiders
Some hack "mechainic" did some clearance alterations to a beutiful Shimano Saint crankset.
The "mechanic" ground the granny thread posts in such a way as to render them unusable. Shitty workmanship.
I was asked to fix this. I faced 3.5 of the posts flat. The last one was not fully faced since that would leave too little thread for mounting a ring.
4 spacers and this crank will be usable again.
We only have one lathe in the shop with a swing big enough of the crank, but we would have spent way too much time making a mandrel to hold the crank, so I used the mill and got completely acceptable results.