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Vacuum Pucks:

"Pucks"or "pods" are small pieces of non porous material which can be used a miniature vacuum hold downs. they can be used individually for smaller projects, or "chained" together in a series situated all around your table to hold larger items. Their advantages are that they are very portable, and versatile. And they can also be run with the use of a smaller "laboratory"type vacuum pump because they don't NEED a huge movement of air (CFM). ALL vacuum systems work by the evacuation of air underneath the part being cut. With "full table"systems this can mean a few hundred feet of channels, or grooves cut into someone's table. This means you will need a pump large enough to evacuate ALL of the air in those chambers. To do this requires a high volume pump of some sort (ranging from a Shopvac to a large regenerative blower)to maintain the high CFM needed to empty all of those channels.

A smaller laboratory pump will not be able to maintain the air flow for this job! BUT if you are only using pods/pucks you only have to evacuate the air inside the gasket tape on the surface of these units, and that usually totals a few cubic INCHES,instead of cubic feet. And this is where the smaller pumps have an advantage. They can generate up to 29"of mercury (units of measurement for determining strength of vacuum. The higher the number, the better with 29.99"being considered the maximum possible...). The larger pumps may have more air flow, but they can rarely generate more than 15"of mercury, so the trade off is pretty obvious. If your work involves the use of different parts every day, OR if you never cut large sheet goods, then pods/pucks may be the right system for you. They are cheaper, more adaptable,and can be made out of shop scraps as well...

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