Instead of relying on the antique hard-plastic vacuum lines or new vulcanized rubber, I collected several colors of 3mmIDx8~9mmID color-matched silicone tubing from eBay. It won't harden, melt, crack, tear, or degrade from UV. Black is usually ~$0.50/ft (~$1.5/meter); colors are about double that.
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![siliconevac.jpg Instead of relying on the antique hard-plastic vacuum lines or new vulcanized rubber, I collected several colors of 3mmIDx8~9mmID color-matched silicone tubing from eBay. It won't harden, melt, crack, tear, or degrade from UV. Black is usually ~$0.50/ft (~$1.5/meter); colors are about double that.
[url=https://www.supermotors.net/registry/media/1166439][img]https://www.supermotors.net/getfile/1166439/thumbnail/hvacvac.jpg[/img][/url] . [url=https://www.supermotors.net/registry/media/1151310][img]https://www.supermotors.net/getfile/1151310/thumbnail/09vacsilicone.jpg[/img][/url] . [url=http://www.supermotors.net/registry/media/894687][img]http://www.supermotors.net/getfile/894687/thumbnail/vaclinesefi.jpg[/img][/url] . [url=http://www.supermotors.net/registry/media/767412][img]http://www.supermotors.net/getfile/767412/thumbnail/recircline.jpg[/img][/url]](https://www.supermotors.net/getfile/1090170/fullsize/siliconevac.jpg)