That riser pour trick finally saved my back and my finish quality

I do a lot of tall risers for stair stringers, and I always fought with trapping air pockets at the bottom of the mold. Last month I tried pouring from the side gate instead of the top, angled at about 30 degrees, and it cut my reject rate from maybe 1 in 4 down to 1 in 12. The metal flows uphill and pushes the gas out ahead of it, so the venting actually does its job. It took me three tries to get the angle right, but now I set up a little wooden wedge under the drag and it works every time. Has anyone else tried side gating on tall sections, or do you stick with top pour and just add more vents?

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the_jenny10d ago

Took me a week just to stop knocking the wedge over with my own boot.