An open center valve is just that, all ports (p, t, a, and b) are connected when in the center position. This will allow the weight of the upper die/cylinder rod to fall down. You need a tandem center valve to hold the cylinder in a fixed position. Most valve manufacturers make flow controls and relief valves that sandwich between the valve and the manifold making it easy, no plumbing. As already mentioned you must use a relief valve, very dangerous with out.
Thanks Wayne-o, very helpful info. Looks like I have the wrong valve then. I think I found the right valve I need with a tandem center. Hopefully they will let me return the other valve. Also going to pick up a relief valve and flow control valve. Thanks for all the help everyone
I found a frame just like your at an auction and I was going to make an lover press out of it after I won the bid the auctioneer told me the rest of the ban saw was over on the other side of the field and I got the complete ban saw for metal with 20 extra 16 foot blades still want to build a louver press still looking but have the louver dyes waiting
FrozenMerc is bang on(no pun intended). When you get to the end of the stroke of your cylinder or die(whichever comes first)either up or down you will want to limit the pressure created by your pump, hence the need for a relief valve.You will also be able to tune up the pressure needed for different materials or dies also.You should be able to buy a segment to go between your DCV and the lower manifold it is bolted to, that will have metering valves(speed controls) built in which will solve that problem.They can come with a bypass in one direction to speed up your up stroke but limit the down for better control while louvering. Maybe a single acting,spring return cylinder would be better for this job,just a suggestion. Love the frame by the way.
I thought about a single acting cylinder with spring return but I wanted to be able to jog the upper die down to line it up. Thanks again to all you guys helping out, I really appreciate it!
Caddy-- I can't debate the hydraulics(valve) theory here , but you may want to research this a little further before your next valve purchase. One wrong "jog" will ruin your whole day. Ask me how I know.
Alright I think I have this figured out. What do you guys think? This is what the plumbing should look like, correct? This is the new valve Im looking at... http://www.northerntool.com/shop/tools/product_200329581_200329581?isSearch=201305 This is the sub plate... http://www.northerntool.com/shop/tools/product_200326790_200326790?isSearch=203231 This is the flow control... http://www.northerntool.com/shop/tools/product_200339399_200339399?isSearch=202512 And finally a relief valve... http://www.northerntool.com/shop/tools/product_200605546_200605546?isSearch=33308 What do you guys think? I think these are what I need, I just don't want to order the wrong parts again
I don't know anything about hydraulics so this is very informative for me. Great build idea too! Posted from the international space station
Looks like you got the right components now. Use the relief valve to set your system working pressure and the flow control to set the ram speed. Good Luck
Be careful with the orientation of the valves,you could easily put the flow control valve 180 degree out if they don't come dowelled.You don't want to mix up the P &T ports The ports are slightly offset to the 4 bolt holes.
Your "C" frame throat at 36 inches will not allow the large car hoods unless you rotate the dies and run the panel sideways through the frame. My shop built press is less sexy than your "C" frame but the throat depth was designed at 48" I opted to use shop air connected to an SPX pump with built in foot pedal that operates an 11 ton SPX single action cylinder. A simple setup that uses little air and allows precise die lineup. I also made my 3" and 4" dies by shaping precision ground and hardened steel. I have a set 3" and 4"dies with matching contours and a 3" set of old school or lakes style dies. You may not have to box your frame. I would test it by punching some louvers first.
Very nice! I am planning to set the dies up so they can be turned 90 degrees. Your louvers look awesome! I also plan to carve some dies out of A-2 tool steel then send them out to be hardened. I used the old rule of thumb that an electric motor hp rating is 3 times stronger than a gas engine hp. I have a log splitter with a 5hp gas engine that splits 18" logs with ease. 1/3 of 5hp is 1.67hp. Researching what others have put on louver presses and hydraulic shop presses, 1.5-2hp seems to be pretty standard
Your diagram looks correct. Be sure and add a pressure gauge so you can monitor the system pressure and adjust the relief valve. If I were designing this for a customer, we would use a system relief valve and a separate pressure regulator to adjust the cylinder force. You should not need this. As you turn down the flow control, more oil will go across the relief valve. This will generate heat in the system. Should not be enough to worry about. But you might want to check the tank temp if you are using it a lot. Log splitters do not have a problem as the pump is sized to use all of its flow to move the cylinder at one speed, ie no flow control. One thing I was taught long ago about hydraulics, a pump only produces flow, no pressure. Pressure is only built in a system when there is a restriction to the pumps flow by either doing work, being restricted, going over a relief, etc.
One thing I was taught long ago about hydraulics, a pump only produces flow, no pressure. Pressure is only built in a system when there is a restriction to the pumps flow by either doing work, being restricted, going over a relief, etc. And flow escaping under pressure without work being done is a heat generator.
Good work. Love these do it yourself projects. 110 volts will be fine, run my home built press at 110 v. with a 3/4 hp. motor, will punch 16 ga. s/s in smaller sizes. If you are going to do modern hoods you may find that a 3 ft. throat is restrictive. You will make your life a lot easier if you go to a hand controlled mechanical (manual) valve. Best of luck, keep up the good work, have fun.
early ford stuff (hood, trunk, etc) is well within the parameters of this fine machine! It will get plenty of use
Excellent presentation, Dr. Josh. Like Albert Einstein said:" If you can't explain it simply, you don't understand how it works." This is a perfect thread for anyone thinking about building something similar. I'll be in line when the "Auburn Louver Works" has it's grand opening.--- Watch yer fingers!
Not quite. Rockets are easy..... Controlling the explosion at the end of a stick is the hard part, and you need hydraulics for that.
Sweet! Great find on the saw frame and love the build. The scrappers in our area have made finds like the frame harder to unearth.
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