Joe Woodworker carries a variety of vacuum pumps. A few are what are called rocking piston pumps. I tried reading about these to understand them but my brain well it cooks up its own ideas of what it wants to know.
So a pump like i have linked to above is a rocking piston type. Does anyone here have experience of these type of pumps?
Thing i dont quiet understand is , they mention in the manufacturers catalog that this is a compressor and vacuum pump. So my question is , does this unit operate on the basis of one cyclinder acting as a vacuum pump and the other on the same revolution of the motor but on the other side as a compressor or do both cylinders operate in tandem where a dual unit like this is just for getting greater vacuum and dealing with more airflow?
So in this event i presume the unit is then either a compressor when you use the one output and a vacuum pump if you use the opposite end output?
Hey what can i say i am a simple guy i need simple understanding. Before i can even venture further.
Next question...if one connects this to a tank of sorts, and draws a vacuum on said tank say for argument sake 20gallons. Then opens the valve on the 20 gallon tank am i understanding correctly that i can get a more rapid evacuation of the item say a bag that the tank is connected to in order to say pull the bag down rapidly initially by faster evacuation of the air rushing into fill the 20 gallon tank? I realize if my understanding is correct that i will not have a full vacuum in either tank or bag at that stage but if the pump was continuously running i would surely have extracted a huge initial amount from the bag or does it not work that way in real life?
Would it be better to simply connect a shop vac to the bag for a quicker initial draw of vacuum? and then switch over to vacuum pump. I am wanting to build a setup to do both woodworking and use the pump to try out making a vacuum forming rig but from what i see in vacuum forming i need to draw a vacuum quickly across the chamber.
Any help understanding this appreciated thanks.
Oh and while on the topic of vacuums has anyone given thought to or tried to "hotrod" their home foodsaver vacuum unit by hooking it up to an external pump of better performance than the junk inside at present.