Saw it. I'm still going to work with my pod design.
A product review has been done by an independent product reviewer on the single sided clamp, the VC4.
The pictures within the review show what the clamps are capable of, and I would also guess that even the reviewer was skeptical of the performance of the unit until it was tested.
Click here for the review.
http://www.cnczone.com/forums/showth...9052#post59052
Errol
Saw it. I'm still going to work with my pod design.
Thanks
Jeff Davis (HomeCNC)
http://www.homecnc.info
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)
I have set up 2 very large 5 axis machines using a vaccuum hold down systems if you can find a old air compressor tank or several freon tanks to use as a accumulator to give you more volume you will have a vacuum system second to none we currently use 75 gallon tanks one for each table (6'x6') two per machine if you have enough pump 1 hp or better you can use 3/4" mdf boards and pull 23 in/hg as long as you seal the edges of the boards (duct tape works in a pinch) and your work piece to the board.
I am talking about holding down a 4'x4' sheet and moving a cutter thru it at 300 ipm on a initial cut and up to 600 ipm with a precut board on a production basis. On a home cnc rig you should not have any trouble as long as you seal up your work board as described above. If you are making a lot of the different parts it pays to have a seperate board for each part setup with a common 0,0,0 point to work from.
Scott
SCOJEN,
Scott, this sound like a very easy thing to do, how did you set it up, do you have any photos, i'm just starting out and would really like to get this style of clamping down pat, i think it would save a lot of programing around clamps and would save re-clamping to cut those areas not accessable due to clamps etc... ebay currently has a few vacuume pumps for auction but non of them say what pressure they produce so I'm not too sure which if any to prurchase.
the other question is can you use a normal compressor and use the inlet as the vacuume suction?
Previously in this forum I had mentioned our compressed air powered vacuum clamps
We now have a couple of new additions that will be of interest to those who need a ready made solution to vacuum hold downs.
Our VC5 clamp will hold itself down to a surface, and then hold a workpiece on top. It has two low consumption vacuum generators built in. The faces can be configured to hold down almost any shape, and no moving parts inside to wear out.
Link http://www.vac-clamp.com/vc5.htm
The other product is a face plug for the VC4 or VC5 vacuum clamp. This is a shim or packer that clips into the face of either clamp. It elevates your workpiece by 3mm to allow you to cut through the workpiece, but not damage the clamp face.
Link http://www.vac-clamp.com/vc%20cnc.htm
Can anyone tell me at what is the MAXIMUM rate air can be sucked through a 1"x1" of 16mm MDF and produce a 0"Hg differential....???
Reason I ask is simple - if you can deturmine the airflow through a 1"SQR of 16mm MDF this should be able to tell us what the CFM rate is required for any given size of table (As a LOSS)
then as you inclease the air flow, the diffirential will also increase and thus you have your vacuum - BUT the hard point is finding this flow rate
NOW!! I know all MDF is slightly different so a ball park figuare would be OK
G'Day Salty,
Through experience we have found that all manufacturers of MDF have differing densities. Some even manufacture a "low density fibreboard" which has the porosity equivalent of wire mesh.At the other end of the spectrum, we have used some European MDF which is perfect for our clamps but lousy as a spoil-board.
One of the other variables is when you skim cut the surface a few times the thickness will change the porosity too. You would also have to look at how much coverage you would have of your spoil-board as well.
Great question for debate I think.
Nice. How big a peice can the VC5 effectively hold? What about wobble on the edges as the router presses down? Or are you saying you need many of these for ,say, a 20" x48" workpiece?