How to cut heavy rebar? Info needed.

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I need some advice on cutting size 8 (1 inch) rebar, the thick stuff. I'm involved in a project that will require cutting about 500 straight pieces into smaller ones, about 2000 cuts in all.Under consideration is an oxy-acetylene torch, plasma cutter, chop saw, radial saw with a metal-cutting blade (Makita makes one), electric-hydraulic rebar cutter, and anything else.I have a torch, but would buy any of the other options. This is a one-time project so I don't want to "invest" in a tool that I'll probably never (or rarely) use again. I don't really need to own a plasma cutter, for example.Renting isn't an appealing option because the project will take several months, and I need to make cuts as I go along.The quality of the cut isn't really important, by the way. Nor is the speed of the cut, either, within limits.How well would a common chop saw work, one with abrasive disk meant for metal? I'm concerned that I'd go through so many disks that the cost would start to be significant.I could buy a (relatively) cheap Chinese-made plasma cutter. I see 50- and 60-amp models on eBay for about $500. Would they have the capability to handle 1-inch rebar?The purpose-made electric-hydraulic rebar cutters are appealing for a variety of reasons. But one big enough to cut 1-inch stuff costs $1500 to $2000. Not appealing just for this project.I've used my torch a bit, but I'm going through a lot of oxygen. So cost and refill hassles are making that option not very appealing. Not to belabor the point, but it's one thing to cut Size 4 rebar (1/2 inch) and another to cut Size 8. I've found that saws that can handle Size 4 without any problem often aren't practical for Size 8.Anyway, I'd welcome suggestions from anyone who's been down this road before.Thanks.-- Mike
Reply:I'd go with a GOOD abrasive wheel chop saw..Get the GOOD wheels from MSC and they will last for around 100 cuts each...And don't forget the saftey glasses.....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Dont know if you have access to a hydraulic pump or not..... but they used to make just a little rebar shear that used it.  I think I saw one at harbor freight once for like $30, but havent seen them there in a bit.  Not sure how well they work or what their capacity is but might be worth taking a look at.
Reply:Found this onehttp://cgi.ebay.com/Hydraulic-Rebar-...item5d28c33e32but it doesnt have the capacity.  I dont know if they make a larger one or not.
Reply:A rebar shear will be no good for #8 rebar. We tried one on a big job with #6 and the cutters don't last very long. Will this rebar be used for structural concrete? I can't remember if there is a rule of thumb about burning structural rebar. I will check with one of our civil engineers. You should put too much heat into it if it will go into concrete because it changes the thermal properties of the steel (shrinking & expanding). I have seen lots of rebar burnt off though.As fara as making a few thousand cuts you would probably be best with a oxy-propane setup, especially if you already have a torch, just get a propane tip, make sure your hoses are rated for propane, grab your BBQ tank and you are good to go!Abrasive cutoff will cost you a couple of hundred bucks and you will surely go through a handful of blades. Don't bother with a cheapo plasma, you will regret it.
Reply:I checked with one of our civils and the big no-no is bending your rebar with heat. So cutting it with a torch should be fine unless you are building a high-rise or something.
Reply:how do those hydraulic sheers work for smaller rebar say #3-5?
Reply:Hacksaw?        You did say that speed was not really a concern.  Yeah, there is a difference between cutting 1/2 inch bar (#4) and 1 inch bar (#8).  The bigger bar has 4x the material to cut through! (that whole area and r^2 thing, ya know)Abrasive chop saw.  Don't know if your applicable building codes allow torch (oxy-fuel or plasma) cutting rebar or not.  Epoxy coated bars are not to be torch cut, only shear or abrasive cut.  A refurb heavy-duty cutter for #8 bar is listed as $1341 at Benner-Nawman, but none currently in stock. http://www.bnrebartools.com/Products/spotlight.htmlLet's see.  Abrasive chop saw at ~$200 and 20 cut-off wheels at ~$10/ each (using zap's 110 cuts/wheel lifetime) = $400 Rough numbers.Dude, you're cutting 500 pieces of #8 bar four times per bar?  You've got what, >$5000 in rebar.  Spring for the $1500 and get the h-d cutter.  Sell it when done for $750-$1000 and it would cost you only $500-$750 result.  B-N claims their cutter blocks are good for 8k-10k cuts and results in about a 1 cent cost per cut (I didn't verify their numbers, I think that may be just the replacement cost for the cutter blocks and not the entire machine purchase + power costs).  YMMV.A plasma to cut through 1 inch rebar would probably be a minimum Hypertherm PM45 (or equivalent).  Price about $1500 new.  Plus you need to feed it clean compressed air and electricity (240V).  That's about the same machine cost as the dedicated rebar cutter for #8 rebar.Your call as to what you want to do or where you want to spend your time and money.btw, what are you building that you need that much rebar?  The best laid schemes ... Gang oft agley ...
Reply:Having made many hundreds of thousands..yes, hundreds of thoudsands of those cuts, I'd grab a torch first and a chop saw or quickie saw second, depending on where I was. Some engineered jobs will not let a torch touch rebar or even on the premises. In that case, a chop saw or quickie saw will always work.If it was to be cut in the shop, I'd look at gang cutting with a large bandsaw. I have a Jet 7x12 and would probably try gang cutting 4 at a time to start.Also, you really haven't lived until you have cut #32 bar......now THAT is heavy. Last edited by DDA52; 04-16-2010 at 02:59 PM.QamuIs Heg qaq law' lorvIs yInqaq puS
Reply:I'd go with the torch---you have it, there is less moving of the long pieces, makes for less time and labor cost...
Reply:How well would a Portaband work?Seems like something one could use in the tool shed anywayEd Conleyhttp://www.screamingbroccoli.com/MM252MM211 (Sold)Passport Plus & Spool gunLincoln SP135 Plus- (Gone to a good home)Klutch 120v Plasma cutterSO 2020 benderBeer in the fridge
Reply:What about farming out the job to someone with an iron worker or big bands with auto feed? For the band saw they could gang them together in tight bundles and metal pack strap them together in the section lengths you need. On the cheap, you could go with a chopsaw. On occasion, I've ganged together 1/8 x 1" flat and clamped it in the saw and hooked a weight on the handle of the saw and locked the trigger. It let me do some bending while it worked it's way through. That's my cheap "suto pilot" 200amp Air Liquide MIG, Hypertherm Plasma, Harris torches, Optrel helmet, Makita angle grinders, Pre-China Delta chop saw and belt sander, Miller leathers, shop made jigs etc, North- welders backpack.
Reply:Where are you located?  I'd imagine one of our members might be happy to farm out the cutting duties or let you use their equipment for a donation of sorts.If thats out of the question I'd buy a portaband.  I have a Dewalt heavy duty deep cut model and have never looked back.  Just make sure you buy the thick blades dewalt makes if you get a saw that can take them, the milwaukees IIRC are .020 thick and the dewalt HD blades are .025 thick and it makes a world of difference.I'd also invest in a quality "stick lube" to make your blades last a bit longer.  You should be able to get some from Lawson or Wurth.
Reply:There are currently several dedicated electric and manual rebar cutters on Craigslist pretty reasonable. Couple good examples here.NEW 1" (#8) Electric Hydraulic Rebar Cutter - $390 (Dublin, OH)Rebar Cutter Electric Heavy Duty (multnomah Co) Bosch 1-14" cutter $225If you can spec your pieces ahead of time any good structual steel place will do it so cheap your head will spin.  I have a huge number custom bent for a barn foundation, couldn't believe the price.Good LuckMarty
Reply:plasma
Reply:What grade of rebar is it? If it is a higher grade[#6] then a chop saw will use up a lot of of blade and won't get 100 cuts a blade. If you don't get one of the rebar cutters then you need to go with the torch. It doesn't care what grade it is and if you have it set right with the right tip it will be the cheapest.
Reply:Grab your torch I'm sure after a couple hundred cuts you'll be cutting like a pro.
Reply:buy a large tip for the torch you already ownnot something rated "just enough" for the thickness, go to the next larger size, easier cutting because of faster preheat and higher 02 flow"Any day above ground is a good day"http://www.farmersamm.com/
Reply:I'm going with the torch also. Simply cause it's how all the batch plants around here cut it and they cut alot of it!HH187Hobart 500i plasma cutterClark 4.5" GrinderDewalt 14" chop saw30 gallom 1.6 hp compressor10 gallon pressure pot sand blasterlots of hand tools
Reply:The only reason not to use a torch on rebar destined for structural concrete is that the heat will alter the thermal properties of it, then when the temperatures change the rebar and the steel will have different coefficients of thermal expansion.The OP has to chime in here on what he is doing all this for, for all we know it could be for a sculpture! Then you could cut it AND bend it with a torch all day long and it won't matter!
Reply:rebar cuts very easy for me with an oa torch. i dont think you need a lot of tip, because the preheat isnt really trying to plunge through 1" material..you get the cut going on the radius  and then turn into the meat of the bar..butter..
Reply:dollars per cut and speed your not going to beat a torch,   Second best would be a rebar shear, you could purchase this up front for the job then sell it when the job is over.   Rebar is really a low grade crap steel, i wouldn't bother trying to cut it with a band saw or a toothed blade.   One big carbon pocket and you can wipe out the teeth on the blade in an instant.  Chop saw would work but slow, noisy and dirty.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:Thanks for this. Answering questions: I'm disassembling the structure of a three-acre fernery. All told, there's about 35,000 lbs of rebar, most of it #8, most 10 feet or a bit longer. Those pieces (components) I don't sell will be cut into smaller sticks and sold to a scrap dealer. I'm not in a hurry; there's a lot of digging involved, too. It seems that a lot of people have experience working with smaller- diameter rebar, but not many have cut much #8 or bigger, including myself. We all realize there's a difference, but until you've tried to do it, it's hard to appreciate how great the difference is. Anyway, this is one-time project. I'm willing to spend the money to get the job done, but before I bought a $1500 hydraulic cutter or plasma cutter, I thought I'd check with the braintrust here. As you can see, I'm getting all sorts of advice. So what's new? :-)
Reply:Well then if it is just going to the scrapyard use a torch....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:I do demo work and by far I would say oxy/propane. We also use gas chop saws but they grow feet easy, get rolled over easy, and for the thick stuff will eat up blades faster."Where's Stick man????????" - 7A749"SHHHHHH!! I sent him over to snag that MIC-4 while tbone wasn't looking!" - duaneb55"I have bought a few of Tbone's things unlike Stick-Man who helps himself" - TozziWelding"Stick-man"Originally Posted by weldbeadrebar cuts very easy for me with an oa torch. i dont think you need a lot of tip, because the preheat isnt really trying to plunge through 1" material..you get the cut going on the radius  and then turn into the meat of the bar..butter..
Reply:Originally Posted by salem747The only reason not to use a torch on rebar destined for structural concrete is that the heat will alter the thermal properties of it, then when the temperatures change the rebar and the steel will have different coefficients of thermal expansion.The OP has to chime in here on what he is doing all this for, for all we know it could be for a sculpture! Then you could cut it AND bend it with a torch all day long and it won't matter!
Reply:Originally Posted by Jay OGrab your torch I'm sure after a couple hundred cuts you'll be cutting like a pro.
Reply:for demo work.  TORCH TORCH TORCH TORCH.    did i mention torch?  personally worked for me on everything from #2-#12 bar.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:Oh sure, NOW you tell us it is demolition work.Torch.  Be safe though.  Heat, molten metal, flame, and stressed metal jumping around can be dangerous.  The best laid schemes ... Gang oft agley ...
Reply:Originally Posted by Sinclair33Hi,I have always used a set of big bolt cutters if I don't care what the ends look like. Just place one handle on the ground and slide the rebar through and pull the other handle down.