Since I noticed that a lot of folks have picked up the robinair pump within the last two weeks, please make sure you are aware of how the pump works in order to get the most out of the pump.
The one most important thing you need to know about oil rotary vane pump is that it is made to run only at 30" of mercury. The mechanical parts in the pump are very sensitive and can wear down very easily. If you have a big leak in your layup and the pump is constantly pulling air then don’t expect your pump to last very long. You will also notice that the pump will gradually lose its ability to pull full vacuum very quickly. So be sure to open up the pump only when you are applying vacuum to a part. Don’t let the pump run freely, sucking in open air or run at low pressure for a long time. Be sure to change out the oil at least every 500 hours of run time. Take good care of your pump and it’ll take care of you.
If you’re working with a large layup, you should consider using a regular oil-less pump to remove the initial air displacement inside the layup. Once the bag is sucked down, switch over to the oil rotary vane pump and let it take over from there to achieve full vacuum.
shop vac to suck down the big laminates first. Thanks Evan for the heads up on the use of the pump