Metal Casting Zone

]

What if you put a small core inside that area ??

I would put a sprue in to the right of the 3" and 2 smaller risers off the other end, on the cylinder and the base. Then I would put a couple soda straw sized vents just above your initial where it shrinks. Build up the sand on the top to give it extra head pressure. Throw a shovel of sand on top, after the pour, to hold in heat until it sets.
I may be totally off in the head, but I was reading Terry Aspin's book on gating last night. I think it was Aspin?/

He still might have a problem with the sprue cooling before the part unless he matches
the thickness. fitting a core into the bottom will take the thickness out and make for a more even cool..... sounds good in theory any way

It would be a big sprue, about the same amount of metal as the part.
The core would work fine as long as he doesn't need the "beef". I think it's for a lathe.

yea its for cutting internal keyways and splines and such, the only reason i keep my old shaper

<tapping head with pencil hoping for a brain storm>

If it got worse with more/larger risers.....maybe a longer thinner runner with a huge riser so the pressure would be up untill the runner cooled then it wouldnt rob so much from the part??? heck if i know best bet find an old foundryman