Cutting thick steel

[56FordGuy]

I've got a large piece of steel to cut, and am looking for some new ideas. The piece in question is roughly 4' square and arches with a thickness that varies from 4 to 8" depending on where exactly you measure across the arch. I need to cut about 1' off the overall height. The cut needs to be fairly clean, but not perfect. I can clean it up with a grinder once I get it cut.

I have a wide selection of saws/ grinders/ torch, etc. My torch is not big enough to do it in a single pass. I've contemplated trying to make multiple passes with the torch, but that's going to be slow and use a lot of fuel. I've had a couple of folks recommend either a gas powered saw like they use to cut concrete or an oxygen lance. I don't know if there are blades out there for those cutoff saws that are designed for metal like this. Oxygen lance looks like a good plan, but I don't have one and don't know anyone that does. I'm willing to buy one if the price isn't too high, but all the welding suppliers are closed today so I can't get prices. If I have to rent a saw/ buy a tool to do this I'd like to stay under $200.

Ideas?

 

[Kevin54]

You know anyone that has a mill or a cutoff saw? If you have to rent or buy something just to cut it, send it to me and I'll mill it off for you for the cost of shipping.

 

[A_Pmech]

An oxygen lance will do it, but the cut will be anything but clean.

Are you certain your torch won't cut 8"? Most mid-line torches are rated to 12" or so, but that requires a manifold of acetylene cylinders or propane. I will say, with those size tips you don't want to be using a standard 8" extension cutting attachment.

 

[56FordGuy]

Kevin, I appreciate the offer but I think this is a bit much to be shipping. The rough weight estimate is somewhere in the 3,000 lb range.

A_Pmech, my torch may be able to do it but my acetylene tank is nowhere near big enough. I have a 100 lb propane tank, but would need to upgrade hoses, cutting extension and buy a large propane tip. That's an option I hadn't really considered, but may be a good way to go.

 

[A_Pmech]

I have a 100 lb propane tank, but would need to upgrade hoses, cutting extension and buy a large propane tip. That's an option I hadn't really considered, but may be a good way to go.

That's what I would do.

Use a section of angle iron as a "straightedge", it's a 5-10 minute cut.

 

[Kevin54]

Kevin, I appreciate the offer but I think this is a bit much to be shipping. The rough weight estimate is somewhere in the 3,000 lb range.

A_Pmech, my torch may be able to do it but my acetylene tank is nowhere near big enough. I have a 100 lb propane tank, but would need to upgrade hoses, cutting extension and buy a large propane tip. That's an option I hadn't really considered, but may be a good way to go.

I misread it. I thought it said 4" square, not 4' square

 

[va.grouseman]

Not trying to be nosy, but why alter an awesome hunk of steel like that. Most shop hounds would kill for an anvil/vise table top like that. You must have a specific project in mind.

 

[56FordGuy]

I do have a specific project; ballast weight on the back of a tractor for loader use. It's an old forklift counterweight, and has some large openings in it in addition to the arch. Pretty much the only thing it's good for is being heavy, right now it's just a little bit too heavy.

 

[Kevin54]

I do have a specific project; ballast weight on the back of a tractor for loader use. It's an old forklift counterweight, and has some large openings in it in addition to the arch. Pretty much the only thing it's good for is being heavy, right now it's just a little bit too heavy.

If you can't fond someone to cut it, you may be able to buy a flat piece fairly reasonably. If you have any junkyards around, the '64-'66 Ford Econoline pickups have a large flat steel ballast underneath the bed of the truck. From what I remember maybe 2'x4' x 4" thick. The Econoline pickups had the ballast weight, but I don't know whether the vans did or not.

 

[shawnspeed]

Ummm a torch may not cut that as it is probably cast IRON...if it does cut it , it will be very ragged at best...it will also be fun to cut with abrasive or other methods as well, because of hard spots & inclusions....good news is cast scrap has value, and you could sell it and buy what you need...55 gal drum with concrete works well for ballast as well...Shawn

 

[bsg]

I do have a specific project; ballast weight on the back of a tractor for loader use. It's an old forklift counterweight, and has some large openings in it in addition to the arch. Pretty much the only thing it's good for is being heavy, right now it's just a little bit too heavy.

Definitely cast iron, the torch cut would be ugly.

You could rent an 14" abrasive saw for cutting stone and buy a bunch of steel abrasive blades.
Probably cheaper than some of the other options.

It's going to be messy, noisy and hot, but doable.

Kevin

 

[bsg]

Something else I forgot to mention.
I sold a couple of forklift counterweights to a local scrapyard, typically they won't take them because they are very hard to break up.
The scrapyard wanted them for dropping on cast iron and on steel, worked great for breaking up machines and compressing material in the roll offs.

Kevin

 

[dogdog]

14" abrasive wheel ? mounted on those hand held gas powered saws?

 

[bsg]

14" abrasive wheel ? mounted on those hand held gas powered saws?

Yes, I have an electric version and it works great.
I have used it for cutting frame rails and floor pans, a bit cumbersome but if you use a cutting guide it works great.

I'm sure the OP will have to make several passes.

Something else, because it is cast you may not have to cut all the way through, once cut 3/4 way through it could probably be split apart at that point.

Another option would be to drill a series of holes where you want to separate it, drill the holes as close as possible and then split it apart from there.

Kevin

 

[bsg]

I just noticed the OP said the material is up to eight inches thick, the abrasive saw wouldn't work unless you can cut from both sides.

Let us know what you come up with and please post some pic's.

Kevin

 

[56FordGuy]

I have to admit, the possibility of this being cast iron hadn't even crossed my mind until it was mentioned in this thread, and I'd bet that's exactly right. Crud. So much for the propane torch.

Scrapping it is an option, but I would rather use it. I need something heavy, and it is. Just needs a little effort to be a bit lighter and figure out how to attach the three point hitch brackets.

Drilling holes isn't a bad idea, but will be time consuming. I think pretty much anything I try to cut this apart will be time consuming, so not a big surprise. I think a combination of drilled holes and the cutoff saw may work. I can cut from both sides, and if necessary I can try driving some wedges into the holes/ cut line to break the last bit if needed.

 

[TOOL_MONGER]

Explosives!!!

 

[A_Pmech]

Ohhh... A counterweight...

A forklift counterweight is probably cast iron, but who knows? It might be cast scrap. If so, it might cut. It'd be worth trying to whack a corner off with whatever torch you have. If it works, you're good to go. If not, you have your work cut out for you.

 

[Spareparts]

I needed to have a counterweight for the loader on my tractor, made a steel box to fit my 3 point and filled it with metal slugs from a punch press from a local machine shop, got them for scrap price. It worked well and was removable in case I needed to attach other implements.

 

[larry_g]

Hit up the local scrap yard, tractor recycler, or metal yard and see if they have a smaller one they will trade you.

lg
no neat sig line

 

[aaronld]

I would be careful not to get that counterweight too heavy then overload the loader. You could end up with a "pasture" split tractor, or a broke front axle. Both cases are a big mess.

 

[macgyver37]

Find a shop with a roll in band saw, they are typically used to do large structural beams so should be set up to handle the weight and size. Might take awhile to get through it, but would be the simplest and best cut.

Jason

 

[R.Anderson]

I don't understand how this piece is and how you want it cut, but would scoring it with a abrasive saw and smacking it with a big *** hammer work?

 

[Dugan]

If your making a counterweight, get a 55gal drum and cut it to the size you need and fill with concrete... why make your life hard.

 

[bsaint]

Waterjet will cut it no issue and the edge will have a really nice sandblast look.

 

[Richard D]

If your making a counterweight, get a 55gal drum and cut it to the size you need and fill with concrete... why make your life hard?

My thoughts exactly.

 

[InPrimer]

Maybe a tractor/supply house that sell weights such as pull tractors use, easier adding specific weight than guessing how much weight should I use??

 

[Crown Imperial]

Hands down use a Thermic Lance.
Only because it's the most fun way of doing this. You can make yourself one.

 

[TLCObsession]

A cutoff saw with a diamond blade works great on cast iron.

 

[Macrosloth]

Thermite? I have no idea if it would work. But the video you could post afterwards would be priceless.

 

[Engine]

I've got a large piece of steel to cut, and am looking for some new ideas. The piece in question is roughly 4' square and arches with a thickness that varies from 4 to 8" depending on where exactly you measure across the arch. I need to cut about 1' off the overall height. The cut needs to be fairly clean, but not perfect. I can clean it up with a grinder once I get it cut.

I have a wide selection of saws/ grinders/ torch, etc. My torch is not big enough to do it in a single pass. I've contemplated trying to make multiple passes with the torch, but that's going to be slow and use a lot of fuel. I've had a couple of folks recommend either a gas powered saw like they use to cut concrete or an oxygen lance. I don't know if there are blades out there for those cutoff saws that are designed for metal like this. Oxygen lance looks like a good plan, but I don't have one and don't know anyone that does. I'm willing to buy one if the price isn't too high, but all the welding suppliers are closed today so I can't get prices. If I have to rent a saw/ buy a tool to do this I'd like to stay under $200.

Ideas?

If you have the means to lift and transport it, you might check with a local metal recycler or scrapyard and see if they can cut it for you. The guys at one near me use some large oxy-propane torches to cut up some huge pieces. They charge about $10.00 to cut up plate, so they might be able to do something that thick. I've seen them cut some 6" stuff.

 

[EdT]

It is likely that it is cast iron/cast trash. Cast iron is easy to drill and very brittle, not ductile. Or, at least, the kind used for weights is no very ductile. If you could get a mag drill, you could drill a bunch of say 1/2" holes along the cut line and drive some tapered pins into the holes to load the material in tension and the give it a whack with a BMF hammer. It would leave a horrible edge, but is fairly controllable and un-dramatic.

 

[56FordGuy]

I drilled small hole in it today, and it does seem to be cast iron. It didn't drill super easily, but produced a fine powder instead of chips/ shavings.

The problem now is more than how to cut it- even if I could hack it to whatever size I wanted I can't weld the steel bracketry required to mount it on my three point hitch. So, it looks like either scrap it and try for something else or cut it into smaller pieces that I can put into a steel box. Cutting it down seems like a lot of work and effort to fit it into a container, so I may go another direction entirely.

Deere calls for about 1,100-1,500 lbs of rear ballast on my tractor for the loader. I want to keep it as compact as possible, and ran across this piece which seemed like a perfect solution. The removable suitcase weights mentioned earlier would work and I could easily build a frame to hold them, but they sell for about $1/ lb and there are much less expensive options. The concrete barrel has crossed my mind, but I have a lot of fairly thick scrap steel around here that I could fit into a steel box and hopefully get the weight I need in a smaller package than a 55 gallon drum.

Not sure what the eventual ballast will end up being, but it looks very unlikely that it will be brackets attached to the counterweight I currently have.

 

[jim keris]

use an air-arc

 

[duhicky]

use an air-arc

easy and cheap! this is what I would use.