 ArtMetalsocial networking for the metal arts |
|
Corten steel vs Mild Steel - Is it worth it?
eligius1427 -
Thursday, November 8, 2007 - 8:48pm
corten steel I recently finished an outdoor installation using 3/8" corten steel. I enjoyed using the material and it looks great. I had to use a dual shield flux cored filler wire, which created some difficulties with overhead and vertical welding, but I made do. The reason I ended up using it, however, was the fear of the mild steel literally rusting away. Take a drive anywhere through the farmlands of the midwest and you'll see old cars, tractors, and other machinery rusting away. Most of this equipment has most of its sheet metal still there(a lot of it fairly sturdy). The question I have is this: If structural strength is not critical, will corten steel last appreciably longer than mild steel? If 18 ga sheet metal has lasted 30-60 years out in the elements, is it fair to say that 3/8" plate steel will 6-10 times that long since it is that much thicker? Since I have to special order the corten and pay for shipping, I have to assume I'll run into some snags and buy extra up front just in case. With mild steel, if I run into a problem I'd just call my supplier and go pick up the steel that afternoon. I would love to be able to direct future customers to spend their money as efficiently as possible. Jake  Welding Corten
visitor -
Sunday, March 22, 2009 - 5:45pm
Can Corten 1/8 inch plate be gas welded? Stuart  Hi Stuart, I'm not sure(i'm
eligius1427 -
Tuesday, March 24, 2009 - 9:39am
Hi Stuart, I'm not sure(i'm assuming you mean O/A welding), but I don't see why not if you can find the right filler rod. So far I've only been able to find a Dual shield flux core wire and stick electrodes for cor ten. If you find the right filler wire for O/A or Tig, be sure to post it, i'd like to get some as well. Jake Jake Balcom Jake I have yet to try out
PeterG -
Friday, November 9, 2007 - 12:46am
Jake I have yet to try out corten, but have seen a number of local sculptures in it that seem to be enduring well. The vast majority of my work is in mild steel with a rust finish because my customers like it that way (both for the colour and the price savings). I typically accelerate the rust by spraying with ammonium chloride and then sprat the sculpture with a mix of linseed oil and turpentine. Even though the customer has to apply another coat of oil every year, it saves on average $1000-2000 per sculpture on galvanising and painting costs, most of which goes to someone else. The problem is with public art. No-one wants to have to maintain it so they want corten or galvanising/paint even if they dont like the look of it. In short, (for my area anyway) big organisations are prepared to pay for low maintenance art, but your average consumer would rather save on the up-front costs. Peter ammonium chloride and oil
visitor -
Tuesday, May 11, 2010 - 11:16am
Do you usually clean your pieces after rusting and before applying the linseed\trupentine mix? What ratio of lin/turp do you use? Thanks Chris Deeper into the Corten VS Mild Steel issue
eligius1427 -
Saturday, November 10, 2007 - 5:17pm
Thanks Rich and Peter for your input. I agree with both of your points. What I'm curious about though, is if the Corten is continually rusting (as proven by the rust streaks around the piece) do you think that it will last appreciably longer than mild steel left untreated. Or more to the point, if the rust runoff wasn't a concern, is there any reason to not use just regular 3/8" thick mild steel(for an art or sculptural piece)? Would it rust away in 5-10years? 30? I've got steel pcs that I've put outside to recycle that haven't eroded that much and some of them have been out there for 2-3 years. Does the Corten rust that much slower to make a difference in 30-50 year span? I realize environment and a whole mess of other factors come into play here in order to give an accurate estimate, but with your experiences what are your thoughts Jake  Jake, Good question. Here's
Rich Waugh -
Saturday, November 10, 2007 - 9:08pm
Jake, Good question. Here's a couple of points to consider: When repairing CorTen shipping containers, they all have warning labels on them stating that all repairs must be made using CorTen or equivalent. Might be worth finding out if there is special welding rod or wire for CorTen. I don't know. 3/8" mild steel will last much longer than just ten years outside, even here on an island in the middle of the ocean. Ydes, it will rust and continue rusting. Yes, it will eventually rust to dust. But not in five or ten years. Maybe in twenty or thirty. In a drier climate, mild steel will last considerably longer. CorTen will last even longer, but will also eventually rust to dust. If you need longer life, use stainless or bronze. I figure mild steel will outlast me, and when I go the warranty is up on all my work. (grin) I'd like to think it will be around for generations, but who knows? In the end, entropy always wins. Thanks
eligius1427 -
Sunday, November 11, 2007 - 10:15am
ThanksRich, I was feeling the same way about the subject. As for the welding wire, I used ESAB Dual Shield 8100-W(Maybe W8100). One of my welding equipment suppliers said this was the appropriate wire for Corten(A588). Jake Corten is a structural steel
vinnieboards -
Thursday, July 15, 2010 - 7:48am
The thing to remember is that Corten Steel was engineered for structural applications including bridge building and steel framework. It has since been adopted in the art world and by modern architects because of the material's aesthetic appeal and lack of maintenance required. Like all steels, thickness will have an impact on the longevity of the material. As has been commented, it will rust down to dust if the thickness is small. Note also that corten should not be used if submersed in water unless the steel is treated. A good site for information is... http://www.masteel.co.uk/corten-weather-resistant-steel.htm Essentially there are two grades (A & B) with B being more suitable for load bearing applications. There are also equivalent grades to Corten which will do the same job. Corten Steel
visitor -
Thursday, June 9, 2011 - 9:36am
Hi There, I have no idea if you are still using this forum but I thought it might be worth a shot as you seem to know your stuff! I own a lot of shipping containers (used for Self Storage) and I am shortly going to have four doors installed in the side of several 20ft containers. There will be four spaces cut out for the doors on the side of the container, and then a special door will be added on to hinges placed on the container. My question is, the steel that is cut out to make room for the doors-would that have a decent recycle value? It would be quite a bit of steel and its from a brand new container so I thought it might be of some value to someone. Any thoughts you may have would be great. Thanks and I hope I am not being to forthcoming here! Regards Michael Conway Welcome, Michael! Yes, the
Rich Waugh -
Thursday, June 9, 2011 - 10:07am
Welcome, Michael! Yes, the CorTen steel from the cutouts would have decent, though not special, recycling value. Basically the same as clean scrap of mild grade steel. However, you could probably get more for it by selling to sculptors or artists for their projects. Where you're located will make a difference in how easy it is to peddle the stuff. College art students, sculptors, or guys who do repairs on containers would be the market, I think. The phone number would indicate you're in Windsor, VA, a good location for that. Welding wire
visitor -
Thursday, June 16, 2011 - 11:13am
8018 stick is used to weld corten. That being the case, 8018 cleaned of flux could be used for either gas or tig welding the same. In the distant past I migged corten and would use the migwire for tig, but I can't recall the mig wire specs at this time. John Christiansen |
|
ArtMetal
Jake, I've seen a lot of
Jake,
I've seen a lot of CorTen stuff that ended up being scrapped because people got sick of it drooling rust streaks all over everything beneath it. That tells me it is continually rusting, no matter what the advertising hype says. Further, most ocean freight containers are made of CorTen, and I see a bunchof them rusted away in five to ten years in our marine environment. I'm sure a dry environment without salt air would make a huge difference, of course. Still, I doubt the stuff is worth the extra money when used for structural size pieces.
Keep in mind, all those car bodies you see intact may very well be galvanized. PaintLok, Galvanneal and other brand names of steel sheet are sold for just that purpose, and they work well. Galvanizing over mild steel is better than CorTen, by far. In the long run, it is probably cheaper, too. Is there a galvanizing facility near you? Might be worth looking into.
Here in the tropics, it is fashionable to make everything from hot-dipped galvanized steel. Of course, the guys who do this forget that welding it burns off the zinc and all their stuff fails quickly at the welds. I use plain steel and paint it with 90% zinc primer over a sandblasted surface and then use red oxide primer and automotive paint. That has proven to outlast the poorly finished galvanized stuff by many years. Properly finished galvanized work will probably last the longest of anything, short of stainless or bronze.
For architectural stuff, I would either use mild steel and paint it properly, or bite the bullet and use stainless or bronze (at ten to fifteen times the cost of mild steel). In the long run, your market willl probably decide for you.
That's my two cents worth, and it's worth every cent, too! (grin)
Rich