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c/foundry-workers

15

angela728•5d ago

I still think green sand beats no-bake for small custom jobs around here in Detroit

I know everyone at our shop raves about no-bake for its strength and finish, but after doing 15 small molds last month for a local automotive client, I found green sand way faster to pack and recycle. The no-bake setup took me 20 extra minutes just cleaning up chemical residue and the smell in our tiny shop got old real quick. Has anyone else stuck with green sand for smaller runs and felt the same about the time savings?

20

kim_davis•6d ago

That moment the sand mold exploded on me in Toledo

I was running a big green sand job last Tuesday at the old Toledo plant, a 300 pound valve housing. Right as I was closing the cope, I heard this weird hissing sound from the vent. Before I could even step back, the whole side of the mold blew out, sending sand and steam everywhere. Turns out the core had a hairline crack from storage and was soaking up moisture. I had to stop the line for 45 minutes, clean out the drag, and re-ram the entire half with fresh sand. The foreman just shook his head and said, "Always check your cores for stress marks before you set 'em." Has anyone else had a mold failure from something stupid like a bad core vent?

27

sam_cooper•6d ago

Spent $400 on a better ventilation mask and it paid off in one shift

I was using those cheap $20 dust masks for years at the foundry, thinking they were good enough. Last month I finally dropped $400 on a proper half-face respirator with P100 filters after a buddy warned me about silica exposure. First day using it, I could actually breathe after a long pour without that gritty feeling in my chest. Anyone else notice a huge difference after upgrading their respirator gear?

17

fionat55•6d ago

The pour floor at that old foundry in Pittsburgh still haunts me

Went to check out a closed foundry near Pittsburgh last month. Walked through their main pour floor. The concrete was all cracked and sunken in spots. You could see where molten iron had spilled over the years. Deep burn marks everywhere. The foreman there said they poured over 200 tons a week in the 70s. That much molten metal just wears everything down over time. Makes you think about the guys who worked that floor day after day. Any of you ever been in a really old foundry and seen the floor condition?

6

kim_mason55•6d ago

Can we talk about the time I spent 8 hours chasing a mold shift that wasn't there?

I was running a batch of gray iron castings last Wednesday and kept getting this mold shift on the cope side that made no sense... I tore down the flask pins, checked the matchplate alignment, even redid the sprue geometry. Turns out it was just a loose core print that I could have fixed in 20 minutes if I'd looked at it closer first. Has anyone else spent half a shift on the wrong problem only to find it was something way simpler?

15

rowan_ross•8d ago

Rant: My furnace motor seized up mid-pour last Wednesday

I was running a small aluminum pour out in the shop behind my house, maybe 30 pounds of metal, and the furnace motor just quit with a grinding noise. The burner lost air and started sputtering, so I had to pull the crucible out fast with tongs before the metal solidified. Turns out the fan bearing froze after I skipped greasing it for 6 months. Has anyone else had a furnace fail right when you needed it most?

9

evan_grant70•10d ago

Had a chat with a retired foundry guy at my local diner in Toledo last Tuesday

He said he never used a safety harness in 40 years and got mad when I mentioned OSHA standards. Made me wonder if old school toughness or new school safety actually keeps you alive longer in this trade.

5

schmidt.iris•10d ago

Changed my mind about using water for green sand after a spill at the Erie plant

I was always team 'add water by feel' until last Tuesday when I overdid it and ruined a whole batch of molds at the Erie plant. A senior guy showed me how to use a moisture meter, and now I check it every time before mixing. Has anyone else switched to using a meter or do you still go by hand?

4

wells.evan•11d ago

My crucible cracked mid-pour yesterday afternoon

I was pouring a batch of aluminum around 2pm yesterday and heard that sound you never want to hear. A crack ran right down the side of my #30 crucible and started leaking molten metal onto the floor. Had to grab the tongs and rush it back to the furnace before it dumped everything. Anyone else had a crucible fail on them out of nowhere or was that just my bad luck?

13

ross.kim•11d ago

Old foreman in Cleveland proved me wrong about riser placement

I always thought risers should go right at the thickest part of the casting... but a guy named Dave with 30 years in showed me a spot 3 inches off center that fed better and cut my scrap rate in half on a 500lb ductile iron job last month. Has anyone else had luck breaking the usual rules on riser placement?

9

charlieh74•12d ago

Why I stopped using silica sand and went with olivine for steel casting

After 12 years of running greensand with silica, I switched to olivine sand for our high-temp steel jobs last quarter. The dust is way less aggressive on my lungs and the casting finish came out cleaner with less burn-on. Anyone else made the swap and noticed a difference in mold collapse rates?

19

noahwood•13d ago

Switched my stance on using water-cooled vs air-cooled cupolas after that meltdown at work last Thursday

Honestly I always thought water-cooled cupolas were overkill for our shop, but we had a runner freeze up on the 3pm shift and the lining cracked in two spots near the tap hole. Took us 4 hours to dig out slag and patch it with a dry ram mix from a supplier in Akron. Has anyone else had better luck with water-cooled setups for high-tonnage runs or am I just unlucky?

12

joseph_green13•17d ago

Cracked a ladle liner during a pour last Tuesday

I was running a 400-pound bronze pour at the shop near Pittsburgh and heard this sharp ping halfway through. Turned out the liner had a hairline fracture from thermal shock that I missed during preheat. Anyone ever test liners with a simple tap test before pouring?

2

lilyt23•21d ago

Why does nobody talk about the hidden cost of cheap safety glasses?

I spent $12 on a pack of 20 safety glasses from a discount bin last month and they fogged up so bad I couldn't see the pour on a big job in Nashville. Ended up with a splash on my boot that took forever to clean because I couldn't react fast enough. Has anyone else dealt with cheap glasses costing more in the long run?

19

rowanw91•21d ago

Veteran pourer told me to stop wetting my molds and I should have listened

Old timer named Gary at the shop in Toledo spent 10 minutes explaining why pre-wetting greensand molds was actually causing steam defects on my pulley castings. He said the moisture content from the muller was already enough if I was doing it right. I ignored him for two months and kept getting pinholes in every other pour. Finally tried his way dry and my reject rate dropped from 15 percent to almost zero. Anybody else had an old hand give advice that went against what you learned in trade school?

27

shane_wilson•21d ago

Guy at the scrapyard changed my mind about cleaning returns

I was over at Apex Metals last Tuesday dropping off some brass turnings and this old timer named Rick pointed at my bucket and said "you're leaving money on the table with all that oil mixed in." He showed me how he runs his stuff through a simple chip spinner he built from an old washing machine motor and now I get almost 20% more per pound. Has anyone else tried making their own spinner or do you just sell it dirty and take the hit?

10

carr.luna•24d ago

Rant: The day our sand muller went down right before a big pour

We were ramping up for a 300-pound bronze pour at the old Johnson Foundry in Spokane, and the muller's main drive belt snapped with a sound like a gunshot. I had to jury-rig a temporary fix with a spare V-belt from an old forklift just to get the sand conditioned in time. What's the weirdest quick fix you've ever had to pull off to save a pour?

1

zarat37•25d ago

Just realized a quick trick for stubborn sand in the flask corners

I was ramming up a complex core for a gear housing yesterday and kept getting weak spots where the sand just wouldn't pack right in the tight angles. On a hunch, I grabbed a small zip tie, trimmed it to a point, and used it to poke and vibrate the sand into those corners before the final ram. It actually worked way better than my old bent wire trick. Anyone got a different method for those impossible little voids?

8

scott.alex•26d ago

Why does nobody talk about the old-timer who taught me to listen to the pour?

He grabbed my arm at the furnace in Toledo and said, 'Stop watching the clock and listen for the hiss.' Has anyone else had a mentor give you a piece of advice that simple but that good?

21

carr.luna•26d ago

Overheard a foreman talking about sand moisture and it clicked

I was grabbing coffee yesterday and heard our foreman, Mike, telling the new guy that a 1% change in green sand moisture can change the mold strength by over 30%. I always just added water until it 'felt right' in my hand. That number stuck with me, so I started using the little moisture tester we have by the muller. After three days of checking, my scrap rate from broken molds is already down. Has anyone else seen a big difference after they started measuring instead of guessing?

27

gray314•26d ago

Shoutout to the guy who told me to use a propane torch on a stubborn core box

Everyone said it would ruin the wood, but a quick pass with the flame on low dried the moisture right out and saved a $200 pattern. Anyone else ever go against the grain on a repair like that?

25

victor651•27d ago

Remember when we had to guess on the riser height for those big steel castings?

Back at the old Johnson Foundry in Toledo, we always had trouble with shrinkage on the big gear blanks, the ones about 18 inches across. The book said to use a riser 1.5 times the section thickness, but we still got pulls. One real hot day about eight years back, I was fed up and just packed a little extra sand to make the riser a full 2 times the thickness, almost as a joke. Poured it, let it cool, and knocked it out... perfect. No sink. We ran with that for every big job after that. Anyone else find their own little number that worked better than the old rule?

8

wade_dixon•27d ago

Switched from a 50/50 sand mix to 70/30 for our greensand molds last month

Always thought the extra clay in the 50/50 mix was needed for strength, but our foreman, Mike, showed me how the 70/30 mix at our Tacoma plant cuts down on gas defects. We ran a test batch on some heavy flange castings and the surface finish was way cleaner. Anyone else try adjusting their sand ratios for different jobs?

24

logan271•28d ago

Had to pick between a new $800 sand mixer or fixing the old one at our shop in Toledo.

The old unit was down for a week and we were behind on core production. I chose to fix it myself, found a cracked gear in the gearbox and had it welded locally. It's running now but I'm worried it'll fail again under a heavy load. Anyone have a good source for a used but reliable replacement mixer?

4

flores.mark•1mo ago

Question about the new sand mix at the Toledo plant

Last week at the Toledo plant, they switched to a new green sand mix with a different binder ratio. We had three castings in a row come out with bad surface finish, like the sand was too hard and wouldn't vent right. What binder percentages are you all running for gray iron these days to avoid that?