What size pneumatic cylinder ( how much force ) would I need to modify a fabric swatch cutting machine. Right now it is hand operated & I can cut 35 pc's of fabric with 20 lbs paper strips glued with Elmer's glue to them by hand with a lot of effort. Right now I'm cutting about a 1 in stack I got the idea that I can remove the handle & install a Pneumatic cylinder to do the work. I got the idea from another machine that is for sale on ebay for $3000. I bought my hand operated one for $125 & they use a hydraulic cylinder the seller told me that cylinder puts out 2500 lbs of force. I'm not sure but I do not think I need that much even if I was cutting a 2 inch stack if I can do a 1 in stack by hand. From looking at the price difference between hydraulic & pneumatic set up, pneumatic will cost a lot less from what I read all I need is a control valve air hose & a cylinder and a air source. The machine has a 12 in blade and the handle is 29 in long I looked all over the web trying to find out how much force it takes to cut a ream pf paper like a stack paper cutter can do but came up with nothing. A stack paper cutter is the closest cutting machine to mine. Thank you for any help in advance.
If no one has a straightforward answer for you, I might have a home brewed way to determine the approximate load required; but, first I need to know if the machine is heavy enough to be operated without any other restraints, i.e. hold down bolts (in your picture it appears the machine is simply setting on a table).
No it has to be bolted to a table or it will slide as you are trying to cut, I think the total weight of it is about 65 lbs
OK, since no one has presented any method for analyzing the cutting load based upon the characteristics of paper, it appears your best option may be to do a bit of expermentation to determine the required lever force so, taking a ground base approach, here is what I suggest. Since the table is securely mounted I believe the best possiblity is for you rig an arrangement using a pulley, rope, whatever heavy materials are available and a simple bathroom weight scale; and, (I suspect you already see where this is going) using these, simply tie one end of the rope to the lever handle and rig the pulley to allow the rope to hang vertically with a weight holding method at its bottom end (this can consist of a sling arrangement of a square section of wood or metal with 4 corner holes and 2 crossing diagonal ropes tied to the pulling rope at their center). Then start and keep adding weights until the handle completes a cut and use the weight scale to determine the required lever and therfore cylinder loading.
At this point I want to give you a cautionary note about one safety issue related to an air cylinder arrangement. The air cylinder has a safety issue because, due to the compressibility of the air, once the cylinder pressure achieves the required cutting load the cylinder is capable of an unrestricted speed in moving the lever handle and this can be a safety risk for anyone near the device when it operates unless an appropriate safety guard is installed.
Just as an interesting technical side note regarding your machine's cutting load is that, since from your pictures it appears that the cutting blade on your machine is parallel the surface of the paper stack, you are only cutting one sheet of paper at a time regardless of how many sheets are in your stack; and, any additional blade loading comes from the blade's friction caused by pushing aside all previous cut sheets, so the machine's cutting load should remain essentially the same regardless of the number of sheets in a stack.
Thank you I will try that.
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