I think that I have a problem with my vacuum pump. The problem is that when I clamp the line between catch pot and my mold (drop test), the vacuum level change. But when I clamp the line between the pump and the catch pot, the vacuum level doesn't change . What's going on???

When I clamp the line like in the photo, the vacuum level doesn't change.

Does your pump have a valve on it? I can't see from that photo. If there is no valve, then when you turn off the pump, air will try and go backwards through the pump reducing the vacuum level which could give you the effect you are seeing. otherwise you have a leak in the hose or around the hosetail barb fitting as the pump itself would unlikely cause a problem when it is running.


Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

Your altitude will certainly make a difference as gauges are a "relative" measurement device so your air is already thinner and closer to a vacuum than at sea level.

A valve on the pump can be quite useful.


Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant