While waiting for my VFD to arrive I have been working on my vacuum work holding system - see attached photo (NOTE: tubing etc… to be better organized once final control panel design is decided on; the manifold is not connected in this test). I have a Gast oil free rotary vane pump connected to an aluminum tank that acts as a vacuum reservoir. There is a vacuum check valve between the two, and a vacuum relief valve on the pump as a safety to keep the vacuum within pump specs. The vacuum to the pods is controlled by a manual plunger style valve T, which I would engage once the vacuum has been reached and the work piece is positioned on the pod(s). The pod in the photo is one I 3D printed for testing. There is a digital vacuum switch connected to the tank to display vacuum. I plan to use it to control the pump via a relay, so that the pump maintains a set vacuum determined by the switch. So far the initial testing shows the vacuum holds well, with only a minor loss over time - this may be due to the only non-compression fittings used at the pressure switch and pod, which eventually will be replaced. The pump pulls vacuum in the tank very quickly, so in actual use I do not see the pump needing to come on very often. Overall the system should add flexibility to other work holding methods I plan to use.
5 Likes