Compared green sand and no-bake for a small job last week. The difference was night and day.

I had to cast a batch of pump housings, maybe 20 of them, for a local shop near me in Cleveland. Normally I use green sand for everything because it's cheap and I know it. But my buddy talked me into trying no-bake for this run since the shapes had some tricky undercuts. Man, I wish I had done it sooner. The no-bake held its shape way better and I didn't have to worry about moisture causing any gas holes. The finish came out smoother too less grinding afterward. Only downside was the cost of the resin and the smell, but for a job like that it was worth it. Has anyone else switched methods for a specific part and seen a big jump in quality?

2 comments

2 Comments

wadeg921mo ago

Yeah that smell is no joke... I stuck with green sand for years just because I was used to it but I tried a batch of valve bodies in no-bake last fall and it was like night and day for the surface finish. The way it holds those sharp corners without crumbling is something else... I actually ended up saving time on clean up even with the extra resin cost.

patkelly1mo ago

Hate to say it but you're right on the money with that surface finish difference. I switched over a batch of pump housings last spring and the first one I pulled out of the mold I just stood there staring at it for a minute. The sharp edges on the intake flange came out cleaner than I ever got with green sand, even after I spent an hour ramming it just right. And the clean up time, man, that's the part nobody talks about. I was used to spending half an afternoon grinding off flash and sand burn, but with no-bake I was done in maybe 45 minutes. That resin cost stings a little at first but it adds up quick when you're not throwing away hours on post-cast work.