Building a New Lathe

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vtsteam:
Then I rammed up the drag, rolled the flask, and separated them. I pressed the handle in, added sprue and riser, Shook out the first cope, set it on the drag again, and rammed it full of sand. Then I pulled the sprue and riser pins, separated the flask again, rapped and pulled the patterns and added pouring basin and gates.

Here's the drag finished:

vtsteam:
I had a little tearout at the wheel hub in the cope -- no draft on the hub since it was machined and I noticed afterwards a small burr there. I'll have to clean the casting up by hand if everything else is okay.

Here's the second cope, finished:

vtsteam:
Took about 25 minutes to melt 3 pounds of brass, and by the time it was ready to pour it was almost dark. I piled some firebricks on top of the flask to weight it down, gave the pot a skim and poured. Spilled a little, maneuvering around the bricks, and the riser didn't fill completely, but there should be enough hot metal to (I hope) prevent shrink cavities. We'll see, later on this evening.....

vtsteam:
Cold short. I can think of a bunch of reasons -- metal not hot enough, die-cast-style spokes are too thin, forgot to vent. I could also move the riser opposite the sprue, though the hub might then have problems.

I may just pad out those spokes, pour hotter, and vent. The finger handle is usable. We'll see. Tomorrow is another day.

tom osselton:
Maybe extend the sprue using a tin can to increase the pressure like myfordboy does and poke the vent holes I’d think that would work.

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