Saturday, May 30, 2015

Pouring again, this time with a little more difficulty.

Following my mostly successful attempt the other night, I decided to up the ante and cast some larger, more detailed, and odd shaped pieces.

To start with, we have the bear "bezel" that started me down this whole casting rabbit hole. Then I chose a bottle opener I found at the craft store for 99 cents since it'd require an interesting parting line. And finally, I decided to through in a couple of the Old Filthy Jar logo patterns I made up a while back. These in particular I expected trouble with because I made them with way too much detail for their size. At best, I think these will only work for lost wax casting but, since I had luck last time, I'll press it.

The four samples fit nicely in my small flask. There probably is a better way to lay them out (as far as order for pouring due to volume and surface area. But I have no idea what they may be so we'll consider this an experiment.

Now, with the drag rammed and parting lines exhumed. Check the parting line on the bottle opener. I thought that was interesting (and why I chose to use it). I did cheat a bit though because you can see the line on the original casting. The bear didn't appear to need a altered parting line, the division between cope and drag seemed most appropriate.

Starting to fill the cope. You can see the char marks from where the extended riser blew out the other night. Hopefully I won't be repeating that.

With both sides rammed, I separated them and removed the patterns. You can see already I had problems with the OF patterns. It pulled up complete sections between letters. They will definitely need some rework to add fillets and drag or be relegated to lost wax casting only. I also haphazardly carved in the runners. I could already tell I might have some issue with the bottle opener placement. Looking back, it might have been better to swap the vent and riser positions so that it got fed first.

Then I fired up the furnace and added equal parts Lone Star muffins (a.k.a crap aluminum) and VV quality muffins.

Once it was up to pouring temperature... a quick swig for good luck. (It worked last time!)

And again, it blew out between the extended riser and the top of the cope sand. At this time, I'd like to point out that there is no aluminum splashed on the top of the extended riser yet you can see the aluminum mushroom coming from the vent hole. This means I am being pretty damn accurate pouring and hitting the hole and I'm not just pouring aluminum all over the place. Either way, the wood and cardboard made a nice cloud of smoke for quite a while. No visit from the fire department this time either.

Once it all cooled down, I busted it open to see how I faired this time. The bear came out great! There were a few defects, but after some clean up, I think it'll be usable. The OF key chains are a wash but we knew that already. The bottle opener, however, was completely MIA. I'm not entirely certain what happened. I had more than enough as evidenced by the blowout up top. Maybe the run was just too long and, after filling both key chains, things had cooled down enough to where the aluminum flow stopped? I don't know. I'll just have to try it a different way next time.

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