Making core plugs for marking out.

[thehomeengineer]

Hi Philip
The plugs are aluminium and considerably softer than the cast iron. Also the plugs are machined to an average diameter so they fit with only a small amount of interference and the aluminium is soft enough to be pressed into the bore. If the cast bores were considerably out of shape or had a lot of flashing I would have cleaned up with a die grinder but this casting had very clear bores. The saddle however needed a angle grinder to dress the saddle before gluing to the cradle.
Hope this answers your question
Andy