Material Choices for Shop-Made Vacuum Pods

CNC owners discuss the options for making your own vacuum pods. July 2, 2008

Question
I am new to CNC machining and considering making my own vacuum pods. I see a lot of pods made from a rubber. This would seem to absorb the vibrations caused by the cutting allowing the part to vibrate more. I see a lot of aluminum pods. These would seem to be more rigid but not have the grid that a rubber pod has.

It seems that two things make a great pod.

1. The less surface area of the pod creates more channeling area the vacuum can grip the part youre holding.

2. The material of the pod that makes contact with the part. Plastics and aluminum seem slippery compared to a rubber. Am I correct in my thinking? What makes a superior vacuum pod?

Forum Responses
(CNC Forum)
From contributor N:
Im thinking that the best vacuum pod would be made out of a rigid material like aluminum. It would have a very thin surface layer of rubber to grip the part but not thick enough to absorb the vibrations.



From contributor E:
Plastic with rubber grip material is the ultimate vacuum Pod for P2P CNC.


From contributor R:
I vote for Delrin plastic with rubber channel gasket. Delrin has stability and is not affected by daily heat swings and humidity. The solid rubber pods seem to flex.


From contributor H:
I made mine years ago out of 3/4" pvc and its still solid and working great. Plus, if hit they can be repaired with PC-7 epoxy, which is almost a dead on color match to the gray PVC available from McMaster-Carr. In the photo you'll see these are screw down pods, but they can easily be made with double faced vac recesses.


Click here for full size image



From contributor F:
We have been using better Better Vacuum Cups for over two years now and I am highly impressed. We made our own pods out of aluminum before but the holding power of the rubber is much better. They don't move and if you crash into one it does not damage your tooling or machine.


From contributor K:
We spent a couple hundred dollars this year and replaced all the pods on our Rover 30 with 1" thick GradeXX Garolite (paper based phenolic) I purchased through McMaster Carr. We machined the pods to accept 5/8 diameter psa rubber non-skid pads just as the originals. We couldn't be happier. The phenolic seems as though it would be a lot more forgiving than aluminum when the inevitable happens and you cut into a pod.


From contributor E:
I did the very same thing few years ago. I replaced a whole set of 18 Pods on my P2P Masterwood Project 327 for the price of two pods from the manufacturer.


From contributor B:
Replacing all of them at once is a guaranteed way of hitting a bunch of them in one pass! I'll never replace all of them at once again.