Melting Bronze in open air crucible versus silver...

[BurningKrome]

I'm using a handheld butane torch (welders) and crucible for melting metals (for molds) in open air. I have a curious question about melting bronze versus silver.
https://www.amazon.de/gp/product/B0002YYQCC/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1
https://www.amazon.de/gp/product/B0165GQUHE/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1

According to the attached chart, bronze has a similar - actually slightly lesser - melting point than silver.

However, I am able to easily melt silver to liquid for pouring (using the torch and crucible)...and yet I can't melt bronze to pouring.

I may need to build a melting furnace. But...

Can anyone tell me why this would be the case?

Thanks!

[Dennis]

The melting points are similar, but bronze is more prone to oxidation when hot. The skin formed prevents it from pouring easily, so it is down to the flux.
It was suggested here that sprinkling on powdered charcoal would help: http://www.alloyavenue.com/vb/showthread.php?2338-Using-Borax-as-Brass-bronze-flux.

Failing that You might try the other suggestions, or try adding a pinch of Tenacity no 5, which I find helpful with soldering base metals. Dennis.

[BurningKrome]

Awesome. Thanks. Is Tenacity no 5 a real thing or encouragement not to give up? (I could use both I think :D)

[Dennis]

http://www.cooksongold.com/Jewellery-Tools/Tenacity-N0.5-Powder-250g-Un2655---Toxic-prcode-PZZ-050

Dennis.