How to cut a 21,000lb cast iron surface plate in half

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Most of you saw the 2 earlier posts on acquiring and moving the 10' x 10' x 12" thick cast iron surface plate to my shop.  Here are some pics of how I cut it in half to make it more managable and go through the doors!First, I started with a Skil saw and 7" x 1/8" abrasive blades.  I used an aluminum tube for a fence to get a nice straight cut.This worked slowly but cleanly until I got just over 1" deep the whole was across.  The saw just didn't have the power to cut the kerf on the sides of the blade when it got very deep.  But, it did get a nice straight starter groove going.  I rented a Dolmar concrete saw next, and put in 14" chop saw blades.  WAY more power!!  Hard on the back and tiring to run, but man did this thing cut!I was able to cut about 4 - 5" deep from the top.  This was nowhere near enough weakening to allow it to crack, though.  I then got the forklift out, and held the plate up to get the trailer out.  Once it was out of the way I snatched the forklift out so it would free fall to the ground - didn't crack though!This plate is heavy enough that the forklift would only lift one side if it was all the way back on the forks.  Any further out on the forks lifted the steer wheels off the ground.  So, I rigged it under the forks with chain and lifted it on end, following it closely with the forklift as it went up.  My goal was to flip it so cut from the bottom side.http://tubularfab.com/upload/plate/05tip.jpgRemove the chains, then push it on over.to be continued...
Reply:Cut all the webs from the bottom to 4 or 5" deep:Lift one end about 3 feet with the forklift, and then drop onto a couple of blocks at one end.  Oh, by the way, I did not cut it right in the middle since that would have been through a solid web.  As shown in this pic, it's about 6" off center so it misses that middle web.Here is a closeup of the cut/crack:With it broken in half the forklift had a much easier time flipping the halves over, and stack them in front of the loading dock.  It's rated at about 8500lbs, so I could only move them from the side.This was one of the funnier parts - reached out through the door and pulled them up and into the building.  This was dead on the limits of the forklift to both lift and pull!  Didn't help that I had almost no overhead clearance to the roll up door and dock overhang trusses.Finally, moved one half into the shop area since I need it this week for a project.  I'll get the whole thing lined up and bolted back together into one big plate later.  I'm hoping the crack acts as a "key" to line itself back up perfectly, kind of like cracked caps on connecting rods.I did everything but the skil saw passes this afternoon, so it really wasn't a bad ordeal.  The concrete saw was definitely the key - that thing is awesome!  Cost me $48.00 to rent it from after 2:00 friday through Monday morning first thing, and was worth every penny!  Of course, it was a real workout running it - I am going to hurt for a few days from that one.  It took 4 7" blades in the skil saw at $2.27 each, and 8 14" blades at $5.97 each.  So, that was about as quick and affordable as it could have gone.PS - the naysayer know-it-alls that posted that this job should have been left to the pros in the other posts need not bother with more negative posts...Last edited by TubularFab; 09-12-2010 at 11:39 PM.
Reply:Nice work!Congratulations on a job well done.Thanks for letting us watch!You and the Clark both deserve a day off. Good Luck
Reply:What is that possibly used for? What / Where did it come from?
Reply:I hope, particularly with the gas-powered saw, but also with the Skilsaw, that you used some good hearing protection!
Reply:Wow. What a huge job. Was there a point during the whole operation when you thought, 'I'm nuts doing this'?That noise must have been insane. I had a bloke come and do some concrete cuts in my bathroom with one of those saws and the noise was nuts. Cutting steel would have been louder than that. And my cuts took about 10 minutes max.Yeah, I carry.House keys, wallet, some change, usually a newspaper, maybe a pen.
Reply:Nice job.Sods Law says it would have broken in two, if you hadn't wanted it to have done.
Reply:I have 3 of those cut off saws.  They're not for precision but theres not a lot they wont cut.    They even make rescue blades that the fire department uses that will cut up and aluminum livestock trailer like nothing.    They absolutely dominate for doing metal decking also.Vantage 500's LN-25's, VI-400's, cobramatics, Miller migs, synch 350 LX, Powcon inverters, XMT's, 250 Ton Acurrpress 12' brake, 1/4" 10' Atlantic shear,Koikie plasma table W/ esab plasmas. marvel & hyd-mech saws, pirrana & metal muncher punches.
Reply:Tubular, I am thinkin, a few  fairly large square box sections under the 2 pieces wil allow them to slide enough to use an angle bracket with  large bolts to align and squeeze them back together enough to make a fairly accurate surface again.  A little ahimming here and there and the use of the bolts/brackets will be enough to close the kerf up and leave only a small line in the table that will eventually fill up with shop smutz to become a non issue.  I would have been afraid of damaging the piece and making it into a bunch of scrap, but you managed to get it done without a disaster, so my hats off to ya.  I dont think what you did will affect the durability or accuracy of the plate in an excessively bad way iether.  I dont have an easy drawing program or a way to upload it, but if you are interested in discussing my ideas to rejoin it PM me and we can figure it out so it is adjustable and stable for the long run.BobI'm spending my Kids inheritance, I dont like him that much anyway!!!!!!Enuff tools to do the job, enough sense to use em.Anybody got a spare set of kidneys?  Trade?
Reply:Good job. Most (younger crowd) wouldn't have put out the effort to get that done. You proved what could be done without the latest high dollar, high tec equipment.PeterEquipment:2  old paws2  eyes (that don't look so good)1  bad back
Reply:Congratulations TubularFab!  What a Saga.  You knew what you wanted, went after it and got it done... shrugging off the nay-sayer's discouraging remarks.  Way-to-Go!  Quite an Inspiration!Rick V 1 Airco Heliwelder 3A/DDR3 CTC 70/90 amp Stick/Tig Inverters in Parallel1 Lincoln MIG PAK 151 Oxy-Acet
Reply:After hearing that you managed to move that behemoth, there should have been no doubt about your determination to cut it.  As for cutting depth.  Have you seen ring saws?  Husqvarna makes a 14" saw that uses diamond ring blades which have no center, so the usable cutting depth is almost twice that of a normal 14" saw.  My local rental place has these, but the rental price can be quite a bit more than the regular 14" saw, since you're paying into the diamond blade.Also, ICS makes a chainsaw for concrete, but they also make chains that will cut iron.  Really designed for pipe, but I'm not even sure where you could rent one of those either.