On Fri, 6 Apr 2018 19:05:05 -0700, Bob La Londe
wrote:

I was sitting here thinking about a tricky mold build. Well tricky for
me anyway. The solution is to cut the mold, assemble it, turn the
outside round, and drop it into a sleeve a few thousandths bigger to
allow for venting, but limit flashing. I am pleased as punch about
figuring out the solution to the problem, but that's not the only
problem. I'm looking at target diameters of .997 and 1" respectively.

I don't own a reamer that big. No big deal. I could buy one and it
would get here long before the job comes up on the board. I just didn't
want to spend the money for one I would use one time in one hole and
never use it again. They aren't cheap. Sure I pay that much for a
fancy mill from time to time, but I get a lot of hours out of it, before
it goes in the recycle pot.

Yeah, I suppose I could bore it on the lathe, but the sleeve has to be
machined into a rectanguloid box. I also need to be pretty close on my
tolerance. If I have deeper grooves inside it could flash, and if I get
it to small it could seize or just not vent well. It would be kind of a
pain to setup.

I'll probably 3D machine the sleeve half in each of two pieces to around
0.990 and then assemble and ream to size.

Than I thought... hmmm maybe I can borrow one from my dad. He has some
old adjustable reamers. Maybe he has one that will cover the 1" range.
He has a set and he offered to just give them to me. I asked him how
much he paid for them and offered to pay for them since I will use it in
my business. Yeah, you can give me some money if you want, but I only
paid $25 for them. Never used the larger ones.

Nice. Two problems solved today. And even the solution to the solution.
IIRC I have some adjustable reamers down in the shop that I picked up
at a yard sale preobably 25 years ago for a couple bucks. I think
perhaps they were for king pin bushhings. Seems to me they were make
and model specific but right now I'm too lazy to put my shoes on to go
look!