a little design help please

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I finished my spring compressor the other day but need to add some support to make some areas stronger.  The main area that needs some beefing up is where the cylinder attaches to the carraige that goes up and down.  I'm not sure what is the best way to stop the flexing and twisting, the cylinder is putting out 1500 pounds of force so need to do something that can handle some force.  Right now the carraige is made out of 1/8" angle, think it is 1 1/2 or 2", don't remember and not by it right now.  Then I have a 3/8" thick peice of flat that is 3" by about 5-6" long attached to the angle.  I am thinking about running some 1/4" triangles from the 3/8" plate to the angle to stiffen that area up.  Then I"m not sure the best way to stiffen the angle up so that it won't flex or twist.  Was thinking another peice of angle the oppisite way or even thought about cutting the angle out and using square tube, don't really want to cut the angle out though.Any advice is greatly appreciated.Here are some picsThis one shows the cylinder extended and connected to the 3/8" plate that is connected to the carraige.  The carraige moves up and down on the angle frame by the brass roller bearings.This one shows another angle of how the carraige moves on the frame and the plate connecting the cylinder to the carraige.Front view.Top view from front.
Reply:Move your ram forward so it's centered under the frame that goes up and down.  That long lever arm off the side of the frame is causing the flex.  If the ram pushes directly on the frame, the only flex will be in the frame itself and the answer to that problem is to build the frame out of larger steel sufficiently strong for the force.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:Desert, I can't put the cylinder directly under the carraige.  I guess I could but that would mean adding another 16 inches or so to the height which I would like to avoid so the spring/strut isn't so high in the air.  I also can't move the cylinder any closer to the carraige because I only have about 1/2" of clearance right now.I thought about it for some time this afternoon and I think my best option is to put a peice of thick wall square tubing in place of the top peice of angle that is there right now.  Then weld the 3/8" plate that is there right now to the top of the square tubing.  Then make some 3/8" thick triangle plates that will sit on top of the 3/8" plate to keep the plate from bending.  Then maybe a smaller triangle plates to go under the 3/8" plate and next to the square tubing.  I think this would stop most of the flex and bending.  The only problem I see with this new design is that it will put the pressure on the 3/8" plate where the ram screws into.  I think it will be alright because if the cylinder is putting to much pressure on this I would think some of the pressure would be transfered to the frame.  The top of the carraige would be pushed away from the cylinder and the bottom of the cylinder would be pushed against the frame of the machine.  So the top roller bearings would also be pushing against the fram to take some of the pressure.  After writing all this I believe that if I can stiffen up the top of the carraige and the plate going to the cylinder I will be good to go.  With no or little flex the carraige would transfer the pressure to the frame which I don't think will have a problem handling the stress.I guess the only way to know for sure is to try it out.  I will cut the top peice of angle out tomorrow and replace it with some thick wall square tube to try and stop any bending/flex there and then make the gussets for the 3/8" plate and this should make the plate reist any bending.  Then the pressure will try to push the top of the carraige away from cylinder and the roller bearings will take some of the pressure.  And the bottom of the carraige will be pushing towards the cylinder and the frame which will take the rest of the pressure.  Sometimes typing helps collect the thoughts and come up with new ones.  Open to any suggestions or advice anyone might have.
Reply:Put your triangle gussets on the bottom of the plate rather the top, so they are in tension rather than compression.  Gussets in compression tend to bend in the middle.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:Thanks for the avice Desert, didn't know that.  There is a brace for the top of the cylinder in the way for any gussets right now but I will notch it and add another one to the back of the cylinder so I will have room for the gussets underneith.  I think I will add gussets on top and bottom, don't think it can hurt.Thanks again for the help Desert,
Reply:I suppose the cyl would be in the way if you mounted it in the top of the frame w/ the rod pointing down so you get it closer to the center of the carriage?                                                MikeOl' Stonebreaker  "Experience is the name everyone gives to their mistakes"Hobart G-213 portableMiller 175 migMiller thunderbolt ac/dc stick Victor O/A setupMakita chop saw
Reply:Originally Posted by mla2ofusI suppose the cyl would be in the way if you mounted it in the top of the frame w/ the rod pointing down so you get it closer to the center of the carriage?                                                Mike
Reply:One other thought would be to duplicate the vertical frame and carriage on the other side of the ram so the ram is centered in the unit. You'd still be loading the side of the frame with the springs, but now you would have the 2nd carrier to help spread the load and support the top plate better..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Originally Posted by ponch37300Thanks for the avice Desert, didn't know that.  There is a brace for the top of the cylinder in the way for any gussets right now but I will notch it and add another one to the back of the cylinder so I will have room for the gussets underneith.  I think I will add gussets on top and bottom, don't think it can hurt.Thanks again for the help Desert,
Reply:Originally Posted by DSWOne other thought would be to duplicate the vertical frame and carriage on the other side of the ram so the ram is centered in the unit. You'd still be loading the side of the frame with the springs, but now you would have the 2nd carrier to help spread the load and support the top plate better.
Reply:Originally Posted by Matt_MaguirePonch you have a number of static/couple load problems going on at the same time here.Lay on your back behind the frame and think of pushing the frame up. Then think of where the bottom of the frame is trying to go (at your head but the cyl gets in the way and the angle iron also catches).The gusset advice is right for the 3/8" mount plate, and you will also have to transfer a large amount of force as low as possible with the moving framework from behind the rod mount at the top.When this couple is fixed the force will be transfered to the main frame itself and then it will flex/bend toward the spring side. This can also be corrected from the back side with a strongback stucture/solution from the top to the bottom of the main frame.The last power parasite is the wheels at the bottom are on the wrong side of the main frame as the force at the bottom is pulling away from the spring side. As it is now you have angle face dragging along angle face at the bottom under load with lots of friction.I don't know what all the offsets are but I'm guessing a little vector math will peg it at 40-60% efficient, meaning about 1/2 of the push gets to the spring and 1/2 gets used trying to twist the frame itself. This is the part of a couple load you have to fight.It looks pretty good so far! As you work through these problems it'll get a lot better.Matt
Reply:I hate to bring up another concern but if the cylinder isn't 100% aligned you will wear out the end seals or eventually break the threads off the end of the cylinder shaft. I would change this to a clevis mount to be safe.ScottFab ManagerWelders360.comNew guy.
Reply:Originally Posted by Scott HightowerI hate to bring up another concern but if the cylinder isn't 100% aligned you will wear out the end seals or eventually break the threads off the end of the cylinder shaft. I would change this to a clevis mount to be safe.ScottFab ManagerWelders360.com
Reply:That's cool ponch, I was just giving you a heads up on where things are trying to move. You'll have to sort them out one at a time like everyone else. I didn't see the plastic strip in the photo, that'll help.Scot pointed out the cyl rod will have a problem at the mount point top and the rod will try to bow some away from the work. This will mostly be worked out when you get the slide worked out.I don't see any major flaws, you're just going to be adding things to the structure to deal with the movements you find.Matt
Reply:That screw to plate connection will be the weak link when I get everything else stiffened up good.  The clevis is a good idea to add a little flexability to this joint.  I just priced one from mcmaster and they are around 40 bucks, pretty expensive.  Think I might try to make one out of some scrap metal and some solid round stock I have, doesn't look like it's anything special.  Ya it's deffinately a learning experience with some aspects of this project.  I knew that it would be when I first started this project, part of the fun.  I didn't see any other parts that needed re inforcing but that might change when I stiffen things up and the forces are transfered to other parts of the machine.Thanks again for everyones ideas and help
Reply:Got sometime today to work on the issues on the spring compressor. Took a good look at it and studied where the forces were causing the problems and came up with some solutions, hopefully! First thing I did was to cut the angle out of the top off the carriage that was bending. This was the weak point and I had some 2x2 3/16 wall square tubing so put that in it's place. I think the thicker wall and being square will stop a lot of the twisting. I also notched the bottom angle of the carriage to allow me to move the cylinder closer to the carriage. I didn't get to drill new mounting holes yet but the cylinder should be within an inch of the carriage which will also prevent a lot of the twisting.  I'm also going to add some gussets under the 3/8 plate that I'm going to weld to the top of the new square tube. I think with these changes all the stress should be transfered to the frame of the machine now. I'm going to add some supports to the frame where I think the stress would have a chance of twisting.I'll try to get some pics tomorrow and that will probably be better than my explanation.Thanks again for your help guys, hopefully I can get this wrapped up this week and paint it and call it done. Have been working on the tire changer I started at the same time a little bit and would also like to get that wrapped up this fall since the garage isn't heated.