Question about pouring gates on small castings

We had a run of about 200 bronze gear blanks last month. The first half we used a single thick gate, like the old foreman taught me. The second half, I tried three thin gates spread around the pattern. The thin gates filled the mold slower but way more even, cut our scrap rate from maybe 15% down to 3%. The metal just seemed to flow better without trapping air. Has anyone else switched to multiple gates for small, detailed work?

3 comments

3 Comments

victor_davis172mo ago

We switched to four small gates on our aluminum pulley castings last year. It made a huge difference with cold shuts and air pockets. The metal just fills the cavity more evenly from all sides. Our scrap went down by almost half.

grant.luna2mo ago

Glad it worked for victor_davis17, but four gates can cause turbulence...

seth_martinez211mo ago

Ever wonder why the old school way is so hard to let go of? Your results say it all. Those thin gates let the metal fill without a fight, so you get less scrap. It sounds like you found a better way to do it for your shop. Sometimes the new trick is just the right trick.