Cast iron?

Thanks guys! My whole barrel of greensand has just about all been used once already aside from maybe another 5 gallon bucket's worth, and I hardly ever touched it, lol, I just poured into it, mulled it, and put it in a second barrel. I'll have to swap the barrels around for next time.

The second set of plates were picked up today, and friday next week we pour the last four, looking forward to it. Everything's ready, except I already still need to weld a new slag scoop onto my skimmer tool because after 11 melts all that's left is a mostly melted away stub where there used to be a nice thick forged spoony end that I'm glad I didn't take that long making. I chopped what's left of it off and hung it up on the wall with the rest of the decorative frozen metal spills etc. in the casting shed.



I put together some video from that crazy week, mostly the second day of pouring the iron plates, but also a few clips from day 1, and also some scenes of the aluminum boulder sculpture from the art casting thread now installed in the sculpture garden, taken at the Oeno gallery's annual celebration.



Jeff

 

I'll let you in on the super special secret: the yellow can is waste jet fuel. I may or may not know someone who knows someone who works at an undisclosed airport and got him a free barrel of the stuff when he supplied the barrel. Red can is just diesel + WMO. I'm really not sure how much difference super secret special vs regular dragon sauce actually makes, but the yellow can is more fun so I'm only using it to start up. Looking into maybe getting a barrel of it for myself if there's still a way.

Jeff

 

I could probably scare some up. We're booked to pour the last 4 plates on Friday, maybe we'll try that.

Jeff

 

Thanks SRH. Maybe for all the wrong reasons but the cardboard definitely seemed to work once we figured out if it is fully soggy not just wet it will last long enough to set down the crucible on top of it. It had stuck and has to be knocked off on all 6 subsequent melts in that 7 pour session, but the next time once we figured out the soggy cardboard, it didn't stick once. I can't argue with that. I will grab some of that cement board when I get a chance, but I've always got extra cardboard boxes I need to get rid of...

Wood ash is an interesting idea to insulate the castings. And I'll pass on the suggestion about annealing it too.

Jacques Gallant, the blacksmith from Montreal who referred this artist to me, can hopefully help her with anything like that that is needed after she gets her castings home. He has a well equipped shop and is very knowledgeable. Last time I convinced her to let me leave the castings in their molds overnight to hopefully cool slow enough despite being open molds, but I suspect next time she'll want to demold and take her castings with her the same day (this Friday) to avoid an extra round trip to Ottawa and back to pick them up before her art show.

For anyone who's willing to click on an IG link, this was Jacques' attempt to pour one of these, after 5 hours in his propane furnace that he knew for a fact could melt cast iron because that's what its previous owner used it for. He's a friend so I feel bad, but I won't blame you guys if you get a small chuckle out of it.

https://www.instagram.com/reel/DLTJ9HmxE2I/?igsh=MXVxczNyeWswYmFqeQ==

As he told me afterwards, now he has a new bronze furnace, and I have a new client.

Jeff

 

The waste jet fuel drip seems easier to switch over to from propane, a little earlier than I can switch to the diesel/WMO mixture. Without the furnace giving me trouble anybow.

But maybe that's all in my head. Maybe I'm just boeing superstitious...

Jeff

 

Haha, that's awesome. I'll have to find some sticker paper for my printer and put nicer labels on my fuel cans!

Casting the last 4 iron plates has been put on hold by the way. Maggy figured she was going to run out of time trying to finish more than the first 10 in time to get them to her show in Switzerland. But hopefully she'll be back to make the rest sometime in the fall.

I'm making arrangements with @G3j to bring by some of his train wheel patterns that he and his steam club members need poured. I owe him, for our crucible swap a while back that worked out too heavily in my favour. Plus I'm eager to find out if I'm pouring iron that will machine well. I have some propylene carbonate (k-bond catalyst, or also a cat for sodium silicate) set aside for Doug too.

I also have a split pattern printed (but not yet the corebox, still in development) for a bronze leadscrew nut needed by a local member of the Canadian Hobby Metal Workers and Machinists forum. I might use the greensand for that too. If it all works out like I'm hoping, he'll be coming by the day before Doug (with some scrap brake rotors for me so I don't run out), so switching everything over to petrobond then back in a hurry would be a bit of a pain. He's got ingredients to make the bronze in the form of copper pipe and some ingots of some sort of tin/lead alloy, from what I gather. Should be interesting. I'll start a separate thread if/when there's any more to say about that.

Jeff

 

I have a chill wedge mold made up already that never got poured... Looking forward to trying it.

So, but without any more open mold planned before the wheels are begin, how would that work? Do I (a) do a whole melt just to pour a wedge test before next weekend's possible wheel casting day, and hope the next melt is similar in makeup, or (b) would I pour the wedge then return the crucible to the furnace until the wedge is broken and examined in order to determine whether inoculation is needed, then add ferrosilicon (or not) and get to pouring the castings from that same melt? The latter option sounds kind of fun, but also like a lot of extra steps to keep track of in an already intense situation. Nobody said it would be easy though, I guess...

I do have ferrosilicon, and was planning on starting with 40g to an A12 crucible based on some advice from various sources* that was surprisingly consistent from source to source. Then adjust from there if things don't work out well. I have a few such doses already weighed out and wrapped up in paper towels, ready to drop in when needed.

* Other sources always welcome!

Jeff

 

@G3j came by yesterday with several molds prepared. 8 train wheels, and some other patterns that were (almost) mounted on match plates. Here's Doug making them fit.



6 of the train wheels were rammed up in 2 for 1 flasks. All rammed up off of match plates that only fit the one half of the flask.





A few challenges presented themselves.

-those sprues were impossible to see wearing my dark tinted face shield. We dusted them for the second pour to highlight the sprues, easy fix.

- 2 of the 3 2fer flasks had copes that rocked a little on their central bar. So you could have one side all the way closed, or the other, but not both at the same time. We just weighted down one side per pour, that worked out ok aside from a bit of flash on one of the wheels.





Here's the only other one that was demolded today. Doug took most of his molds home unopened, unless they were short pours (there were one or two)





- big problems with my gravity feed oil tank/line! I think there must be a clog where the tank connects to the line, and a small leak there as well allowing air to get sucked in and start creating air bubbles that go up and down the line, and stoppage of fuel. There's been a slow drip there for ages but today the fuel just stopped leaving the tank, and the line was just sucking air bubbles into itself. Very frustrating, but it didn't quit completely until what should have been near the end of the second melt. Luckily we were close, and I had a backup propane tank..

We got by, but that might have been part of why one of the molds poured short. The other part was the slag stuck in the bottom of the crucible making it look more full and feel heavier loaded than it was. This brake rotor iron sure does make a lot of it! A lot more than any of the random cast iron scrap items from the 11 art casting pours prior. I don't know if that's because they're kinda rusty, or something about the alloy they are made.from, or what.



I did chill wedge tests for each of the 2 pours. I just poured those first for both melts then poured the rest of the molds immediately.

There was a little bit of chill on the tip of the wedge and a short way up the sides when I used 40g of ferrosilicon in the A12.



But when I used 50g it only appeared mostly on the very tip.



As chunky as the train wheels are, I bet they'll be ok from both pours.

Fun day. I look forward to hearing how machinable the castings are!

Jeff

 

Do they make huge amounts of slag for you? I find myself having to remove slag before it bubbles over the top of the crucible every time I melt brake rotors, leaving only maybe half a crucible of iron remaining. Maybe even a couple times before it's full. @G3j remarked a couple times about how often I was skimming, but even if it was unusual I didn't see much other choice. Given the issues with the oil tank, I decided to pour before it was as full as I wanted once I had a clean looking melt that seemed hot enough to pour (another thing to blame for short pours).

The various types of old cast iron scrap I melted for the art pours made much less slag. Could it be because of rust? I knocked what I could off as far as the flaky stuff, but the rotors were rusted all over and there was likely lots more that maybe could have come off that I didn't get to, inside the vents etc.

Jeff