The short answer - Multiply a part's surface area by 14 to find the downward holding force in pounds.
The long answer - The holding power of any vacuum chuck system is measured by the amount of air it can remove from under a part. You'll see this air pressure measured as "Inches of Mercury" or "Hg and measures about 30" Hg at sea level. A perfect vacuum is when all the air pressure equals 0" Hg.
It is nearly impossible to create a perfect vacuum on Earth however the SmartVac II draws a 93% or 28" Hg vacuum. This is equal to 14 psi. This means a 6" x 6" part having 36" of surface area will be held with a force of 504 pounds (36sq.in. x 14psi = 504lbs).
The perfect part has a large surface area and with a small thickness cross section. Materials range from plastics to softer metals. Harder materials can increase side loads during cutting which can slide a part off the chuck so lighter feedrates and depths of cut should be observed. This can be overcome by sandwiching a piece of 180 grit sandpaper between the chuck and the part to increase friction.
The SmartVac II VCU draws a vacuum equal to or greater than convential vacuum pumps. Plus, the system is low maintenance since it does not require filters or coolant traps. Other systems require an electrically powered pump where the SmartVac II runs off a small amount of compressed air. The chuck portion of the system has nine vacuum inlets allowing up to nine individual parts to be held simultaneously where other systems only hold one part at a time. Pricewise, the system is far less expensive to purchase and maintain than traditional systems.
This is easily done by attaching a Top Plate to the chuck surface and milling a gasket groove just inside the part's perimeter. Any through holes in the part need to have gaskets around them so the vacuum isn't lost when a cutter breaks through the bottom surface of the part.
Yes! The SmartVac II is perfectly suited to handle large parts by two methods. Multiple bases can be setup adjacent to each other using a Twin Base Kit. This kit contains everything needed to chain two bases together and operated by one VCU.
The second method is by using custom oversized Top Plates. These plates are ordered to a customer's specifications and overhang the edges of the Base by 3" in all directions to create a maximum size of 20" x 15.5".
All of our products can be purchased directly through us.
This allows us to establish a close relationship with our customers and provide the best applicaton advice possible. Please visit our workholding store give us a call to place an order at (800)
352-2894. We accept all major credit cards and company checks.
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