theyd both be off load and just sit there doing very little. Assuming you have a sealed bag that is.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

One is a generic chinese pump, same as the EC one, the other is an Alcatel heavy duty one.
I did notice it sucks the air quicker, but I was wondering what it would do in terms of debulking or leaving them running while the part is cooking.

All it will do is suck the air out quicker.  One pump will work slightly harder than the other as there will be slight variations between them.

Guess its a easy way of doing a rapid degassing if you dont want to buy a bigger pump but already have two pumps knocking around.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

I'm thinking the same as Daz...

My thinking is it will pull the bag down quicker as there is a bigger volume being sucked out but i think the vacume wont be any more than standard,

I have 2 vacuum pumps. I was wondering if having both working at the same time will be of any advantage.
I would either put 2 valves on the bag, or hook up both pumps to a manifold and have a hose go from the manifold to the bag.

My question is: Will the total vacuum pull be stronger, or will the pumps fight against each other?