Molding sand grain size

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Harry
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Molding sand grain size

Post by Harry »

I was curious about the mesh size of my sand so I took a pinch and squeezed it in my micrometer. Several tries came out with the same 0.008" so I looked it up and that is 70 mesh. What are you guys getting on grain size?
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mite5255
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Re: Molding sand grain size

Post by mite5255 »

Wow thats about .2 mm, my play sand is about .8mm and under, thats what the supplier to the hardware store were I get it told me. I'm starting to add a finer sand from a landscape supplier to my mix, I'll take some to work tonight and see if i can measure it, my micrometer has a round anvil so it would be damn difficult to measure

Mike
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wikisi
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Re: Molding sand grain size

Post by wikisi »

I use 70 mesh olivine sand. I get it from a local foundry. I asked if I could buy a few buckets full, the guy said you bring the buckets you can have the sand free, he even gave me a tour 8-) Great guy!
mite5255
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Re: Molding sand grain size

Post by mite5255 »

I measured mine at work last night and I got .5mm on my play sand and the new stuff .3mm
When life gets tough, remember: You were the strongest sperm :)
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Nudge
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Re: Molding sand grain size

Post by Nudge »

I think I might go and measure mine! :)

Mine is 0.35mm I checked it 3 times just to be sure :)
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davidbraley
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Re: Molding sand grain size

Post by davidbraley »

What are these millimeters you speak of! That's not a real measuring system! :D

Just kidding. :roll:

Here's an even better site with info on this mysterious "Mesh" measuring system:

http://en.wikipedia.org/wiki/Mesh_%28scale%29
-David

I cut it off three times! And it's still too short!
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_FL_
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Re: Molding sand grain size

Post by _FL_ »

Just saw the technical specs of my greensand recently: Average grain size: 0,09mm. Wow! Petrobond Goodbye.
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Harry
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Re: Molding sand grain size

Post by Harry »

I did not think such a small grain size was a good thing for greensand because of the need to vent steam through the sand. That is 0.003" which is nearly 1/3 rd the size I measured in mine. If it works though I say go for it, I am sure someone has figured out how to get good binding with very little water.
I'd rather laugh with the sinners than cry with the saints the sinners are much more fun...
Muller
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