Thread: where to get lengths of a darker metal pipe from?

Originally Posted by Pakros

Hi all,
First time poster. First time builder too I've decided to undertake a little project at home, and am having difficulty to find anything that is not galvanized steel (very shinny). apparently there is a galvanized black steel but this has a painted blue/black undercoat? not sure what this looks like, from the pictures its very shinny where as i'm after a dark, dark/grey , iron look? (hope im making sense) From what i've found online, what i'm looking for is called black galvanized iron. Something, that if scratched, will not leave a bright shinny mark. Thanks for your time guys really appreciate your help

A traditional hard wearing blue/black surface can be obtained by traditional metal acid fume blueing (some details here)
Along the way to this finish the metal takes on a dark grey gun-metal look which also looks very traditional and sounds like it may suit..
There are two problems - it takes a long time to generate this finish, and you need a chamber big enough to seal the pipes in an acid vapour and then also boil them in distilled water.

How long are the steel pipes?

Oh yeah one more thing this method is not permanently rustproof and it will still eventually rust especially if used in moist environments - if you want rust free you would need to overcoat the metal with a mat lacquer or epoxy of some kind but this my not suit your application.

It would be useful to know what it is that you are doing with the pipes so the help could be more closely aligned with the application.

If its black pipe your after ring around the steel suppliers/metal merchants.

There is NB (nominal bore) pipe. This has a black finish and is specified by the bore size and a 'weight'. So 20NB medium will have a 20mm bore and a wall of some specified thickness, which I can't remember. But any proper steel supplier will be across all that. Or you might find the specs online.

PS: I've never heard of black galvanised. Any steel, if scratched, will look... steely (silver).

hi Pakros

standard 'nominal bore ' pipe comes as:
black (although this could be raw steel, painted (maybe red or blue), oiled or with a hard or sticky lacquer type coating

or galvinised ( shiny or dull silver covering - depending on its exposure to the elements)

any other process to coat the pipe would be done as a special - say powdercoating or electro-coating ( ie. not at the steel pipe mill)

when we talk about 'black' pipe we refer to 'non-galvinised ' pipe - in general

there are of course, other types of tube and pipe

hope this helps

btw - what a great site this is

regards

mark

Thanks for the feedback fellas!
@Bob
its part of a fixture im installing in house to make some shelves from. So it will be in an indoor environment. The longest piece may be up to 2 meters. That process sounds bad ass, i'll have a look into this process as i am looking for the gunmetal look as you say! so thanks, think you hit a nail on its head.

@markaus
Thanks for the info, i must have sounded a bit confused when i contacted the steel supplier asking for black galvanized iron... oh well. I was told from some friends that iron, when it rusts, forms a protectie oxidised coating which is darker in color, while steel forms that flakey rust which can ruin the integrity of the material.

@Bryan and pipeclay
Thanks for chipping in, that shinny scratched look is what im trying to avoid, which is why im assuming i need something that has the dark color throughout the material rather than the color just on the surface.

also looking around, cast iron pipe looks similar to what i want, but is there anywhere in victoria that sells it in 26mm or 33mm?

Thanks again.

Originally Posted by Pakros

also looking around, cast iron pipe looks similar to what i want, but is there anywhere in victoria that sells it in 26mm or 33mm?

Not in my life time and I'm about to turn 50. I'm not even sure cast iron pipe was ever a thing.

Phil.

I reckon the best and cheapest way would be to make your frame and then have it powder coated, that way you can make it what ever color you wanted. It has a fairly durable finish, is available in a matte, satin or a gloss finish. Even for inside decor, metal can rust, it will take longer but will still rust from humidity. I use to make 4wd accessories and all my items were powder coated.
Kryn

Originally Posted by Machtool

Not in my life time and I'm about to turn 50. I'm not even sure cast iron pipe was ever a thing.

Phil.

Hi Phil,
On the days flour mill boiler there was cast iron pipe that was used to get the steam to the engine. Not something that would be allowed anymore but obviously quite successful years ago.
We still use some at work for the exhaust pipe on the Phoenix engine in the battery house. I have included a pic of both.
Hi Pakros,
I can't say I have seen cast iron pipe that small but then I haven't been looking either . I'll keep an eye out.

Phil

DSC_0804.JPG Camera roll 027.jpg

Originally Posted by Pakros

its part of a fixture im installing in house to make some shelves from. So it will be in an indoor environment.

that shinny scratched look is what im trying to avoid,

I'm having trouble understanding why a bookshelf support will be subject to severe scratching. I would have thought any of the usual finishes would be sufficient, eg paint or powdercoat. If you want a 'natural' finish, you can apply rust converter to a lightly rusted surface and the rust will turn into a hard protective coating, purplish or brownish black in colour. You will have to take a run-up with your steam punk Dyson to put a scratch in that.

I cant' think of any metal that's black all the way through, If that's a fixed requirement, maybe black plastic pipe with a steel rod in the center?

Black pipe is just black on the outside, same for black galvanized, it's just the same shiny steel underneath the zinc coating..

Regards
Ray

you guys on this forum are awesome, very helpful, thanks for the feedback.

@ryan : The reason there could be scratches is because im using fittings that clamp on with an allen key (hex nut?) I've done a similar project in the past and used galv steel pipe, primed and painted it and when the fittings were being adjusted (its designed to be modular so you can make changes as you want) scratches occurred in the surface bearing the shiny galv beneath. I was hopping that i could find something with a stronger thicker layer, so if it were scratched it would not leave a shiny streak in the frame . the rust converter sounds interesting i'll look into that! thank you

lol thanks phil and steam, i guess i am definitely NOT looking for cast iron!

thanks a bunch guys!! i think i'll get a sample of black pipe from steeldirect and see what that looks like.
20130612_115904.jpg

A desk i recently made. The frame is galvanized steel painted with a couple different coatings. Black primer, then flat black, then a light coating of gunmetal. If you look at the top horizontal pipe supporting the top shelf, you can see scratches from when i had to move the monitors after i got brackets in.
first thing i ever made that actually worked (by worked i mean didn't collapse on me). I'm hoping to do some more projects like this for friends, so im interested in how to improve on what i've done. Im also trying to devise how to tidy up the cables (and my room).

As mentioned above, i figured if the top layer was thicker/stronger, these scratches wouldn't happen. it would also have a more natural look, as on closer inspection you can clearly tell it was spray painted due to small droplets. (good from far but far from good ).

If you are going to secure your brackets directly onto your pipe work by a locking screw,I think you will always have marks left by your clamping screws.

If you could find a clamping system that uses a split type clamp you would have more chance of not marking your pipe,you may even find that the amount of clamping force to achieve your result will be lessened,further reducing the chance of marking the pipe compared to the single locking screw clamping directly onto your pipe.

If you want something silvery and is the same colour all the way through, use aluminium or stainless steel.

Otherwise forget it. Any steel product used as you intend will get marked up and the marks will show. That's what touch-up paint is for.

PDW

I agree with Pipeclay. You need to revise your clamping system. You need some kind of padding under the screw points, maybe nylon. And if the clamp surfaces are scratching then pad them too. Leather comes to mind. Or felt. Of course they may need to be resized. Personally I would be looking far and wide for an off-the-shelf clamp that avoids the problem. Someone has probably trod this path before.