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Elninio
06-14-2013, 11:40 AM
Last time i went in person to a metal store, they had large wall tubing. I'm looking at my store (metal supermarket)'s website and can't seem to find it. Wall thickness was 0.375 on a 2" tube. I want to see if they have 3" by 2.5" (0.25 wall thickness) before I go there and buy some, but don't know what to look for. I looked under cold and hold rolled, and wall thickness don't approach 1/4". If I could find out the prices online, I could make adjustments to my design. I'm going to build a cnc 4th axis.
http://www.steelpipechn.com/Thick-wall-steel-pipe/1285323580317_hz-fileserver3_5584981.jpg

Jim Doherty
06-14-2013, 11:54 AM
Pipe as opposed to tubing has thicker walls, check speedymetal.

Jim

Dave S.
06-14-2013, 12:02 PM
You are looking for DOM tube. http://www.metalsupermarkets.com/Material.aspx?ProductId=CTRD/3250

Dave

doctor demo
06-14-2013, 12:11 PM
The closest in (pipe) would be: 2.5" pipe sch 80, that works out to be 2.875 od X.276 wall thickness. Otherwise You will have to use tubing but finding a supplier for a small quantity is going to be tough. Not that finding sch 80 2-1/2'' pipe nipples is a walk in the park:(.
A machine shop or hydraulic repair shop might have something, but it is going to take some shoe leather to find.

Disregard all the above if You order a company's minimum, but that may be more than You want:mad:.

Steve

Jaakko Fagerlund
06-14-2013, 01:08 PM
Just today saw heaps of that stuff at the ocal scrap metal yard that also orders and sells 1st and 2nd grade stuff, costing pennies. I'd check them or ask from some local machine shops for drop-off or a cut to length piece. Probably costs next to nothing, if you go and say what you are going to do with it and then tell them what you need :)

If I had to order that stuff, it would be 6 meters minimum or extra high cutting costs (basically almost the same price to buy the whole length).

Forrest Addy
06-14-2013, 02:06 PM
Some other distinctions; pipe Vs tube. Pipe is intended to carry fluids under pressure. It features low carbone and high ductility. Strength is not a big factor in Sch 40 (thie usual stuff for domestic water) which a large corrosion allowance. Pipe properties vary widely depending on the material and the standard is was make to. Oh yeah, market pipe size and actual dimension have only a casual relationship; a legacy of mid 19th century commercial practice.

Tube is usally intended for mechanical structure and is sized by OD and wall thickness. Again there are several standards so be careful if you have specs to follow. Also it comes in a wide variety of materials from lead/tin for organ pipes to aircraft tube to ANSI whatever, mechanical, seamless, welded DOM, hypodermic, copper, brass. The list is long and bewildering if you try to plow through it all. However its all made for specific applications and the sellers make sure their offerings are properly described and classified. Selection poses little problem if yu buy from the dealer. The small consumer purchasing likely looking shorts andremnents should be vigilant. A rusty piece of tube can be continuous cast iron or 52100 steel but can be unmitigated disasteres if welding is attempted..

Thick wall tube is available but you have to look for it and it aint cheap. Speedy Metal seem to have a huge selection of tube sizes. There's a surprizing number of auctions for thick wall tube on eBayn in short and remnant lengths so you might look there but be careful of material.

ckalley
06-14-2013, 04:17 PM
That stuff shown in the picture is what I have heard being called 'hollow bar'. One place I worked had it made to order for a certian job. That way they wouldn't have to hog out all of the material in the center, like they did when they made it from soild. All they did was take 1 pass on the ID with a boring bar and that part of the job was done!

I have some (I think) 2 1/2" OD X 1 3/4" ID aluminum hollow that came from there. I've seen it a couple of other places, used for the same reason. As noted in other replies, you may get lucky and find some surplus, but trying to buy it is going to be big $$$$$!

Craig

cameron
06-14-2013, 04:48 PM
I've usually found that the local Metal Supermarket will order in a small quantity of just about any reasonably available stock metal. You do pay a high unit cost, though, as compared to what you might pay for a larger quantity elsewhere.

KMoffett
06-14-2013, 04:59 PM
Something like this maybe: http://www.mcmaster.com/#cadinlnord/1155t15/=n6z1t2

Ken

Shade
06-14-2013, 05:13 PM
You are looking for DOM tube. http://www.metalsupermarkets.com/Material.aspx?ProductId=CTRD/3250

Dave
DOM is what it is called, stands for Drawn over Mandrel, used when you need a hole through a part, so instead of purchasing sold stock you get DOM and you do not have to pay for material you are just going to drill and bore out. It comes in common in ID and OD, If you want a finished 2 inch OD and a finished 1 inch ID, you need to get 2-1/8 OD Rough and 7/8" ID core and finish machine to dimension.

Elninio
06-14-2013, 07:48 PM
DOM is what it is called, stands for Drawn over Mandrel, used when you need a hole through a part, so instead of purchasing sold stock you get DOM and you do not have to pay for material you are just going to drill and bore out. It comes in common in ID and OD, If you want a finished 2 inch OD and a finished 1 inch ID, you need to get 2-1/8 OD Rough and 7/8" ID core and finish machine to dimension.

At speedy metal markets mart, the DOM is more expensive than solid 1018 of the same diameter (3").

Shade
06-14-2013, 08:14 PM
At speedy metal markets mart, the DOM is more expensive than solid 1018 of the same diameter (3").

LOL, that does not surprise me. In general, it normally should not be.
At my local steel service center it is usually only 5-10% more per pound
than solids are IIRC most of the DOM they stock is 1026 stress proof.

michigan doug
06-15-2013, 02:58 PM
DOM is generally a more exotic alloy than plain jane 1018, and also better tolerances. Plus, you don't have to machine the hole from scratch.

That's the idea anyway...


doug

darryl
06-15-2013, 03:22 PM
I hate it when I ask for something like that, and the guy says 'ooh, that's going to be expensive'