# Metal experts please help!  What steel can I use? Hot rolled, cold rolled, black pipe?



## meatsweats86

Hi All,

Building a fridge conversion and I have looked through this form and searched everything and I don't seem to finding answers to my questions.

I was planning on using using hot rolled angle iron for my shelving brackets, cold rolled sheet metal for door and hot rolled expanded metal for shelving. I found hot rolled mild steel, but the description says "With _*galvanization*_, it can resist corrosion well."   Is this the same galvanization used on galvanized pipes that I need to stay away from??? I found this on http://www.onlinemetals.com/

Also having a tough time finding a 3" x 18" exhaust with a flange I can mount from the inside and up through the smoker.  Is black pipe from HomeDepot/ Lowes safe to use for inlets and outlets? They sell flanges, pipes and elbows that would work great, but I am a bit leery of using this as I don't know how it reacts to heat or if any toxins?  My inlet flanges will be very close to my heating element.

I would prefer stainless, but the price is way over my budget.

Thanks,

-MeatSweats


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## crankybuzzard

Take a deep breath!  

The galvanized isn't what you want to work with for sure.  As for the exhaust, the black pipe would be fine, but awfully heavy.

Check this link below and see about some brick and mortar places around your area.  Their prices will be MUCH better and they will have stuff you can feel and touch before you buy.  For a small fee, most will cut it down for you if they aren't too busy.

https://www.google.com/#safe=active&q=farmington,+mn+steel+supply


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## meatsweats86

Thanks for the reply CrankyBuzzard. I actually priced everything thing out and with free shipping after a certain dollar amount, onlinemetal.com would be the least expensive route compared to all brick and mortar near me, unless I found scraps. I will probably buy local anyways just so I can see what I am buying and support the locals.

The part that concerns me is fact they use the word galvanization in the description. I don't see angle iron offered in cold rolled anywhere and was curious if all hot rolled angle iron used galvanization and maybe other companies didn't list it in the description or if it's just this company that uses Galvanization???

Below is the description I found






[h1]Hot Rolled Mild Steel Angle A36[/h1]
0.5" x 0.5" x 0.125" A36 Hot Rolled Steel Angle is made of low carbon steel that is commonly found in most industries.

Offering good weldability, machinability, and heat treatability, Hot Rolled Steel has a rougher surface than cold rolled steel. 

With *galvanization*, A36 Hot Rolled Mild Steel resists corrosion well.

View our "Guide to Mild Steel" for available grades, shapes and addtional information.


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## crankybuzzard

I think they mean if it's added.  Call and ask to be sure.


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## kc5tpy

Hello.  Sorry I missed this.  I was a welder for almost 20 years.  Hot rolled has what is known as "mill scale" on it.  When you look at it closely you will see it looks a little like snake or lizard skin.  This can be ground off if you need a totally smooth finish.  Lot of work.  Cold roll does not have that finish; it has a smooth finish and is harder steel and is much more expensive.  Neither product should be galvanized unless stated in the description.  All steel that is galvanized SHOULD have the mill scale remove before the galvanize process starts.  VERY doubtful you will find cold rolled galvanized steel.  CrankyBuzzard is correct in my opinion; NO-ZERO galvanized in your build!  Choose the hot rolled unless tool making is the desire or you have money and want a totally smooth finish for visual effect.  For your build I would go with all hot rolled.  Black iron is safe for the stack but as stated it will be heavy.  You can find hot rolled VERY thin pipe for the exhaust.  For the exhaust you can even use galvanized stove pipe which is light and cheap.  Galvanized for the exhaust ONLY in my opinion.  This is all my opinions.  Hope it helps.  Keep Smokin!

Danny


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## meatsweats86

Next question regarding expanded metal. I plan on using .75 x 9 flattened expanded for my racks. They will be 12" deep x 24" across sitting on angle iron for brackets.

Will I need to weld rod around the edge and one down the middle for support, or will the expanded metal be sturdy enough on it's own to hold 15-20lbs?

-MeatSweats


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## meatsweats86

If support rod is needed, what size solid round would be adequate?


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## kc5tpy

Hello.  Will it hold, won't it hold?  I think you should be fine.  BUT!  If I were doing the project I would weld 3/8" bar around the edges and across the middle.  It does not need to be welded in every place.  Skip weld it.  Rough edges on expanded metal can hang up and cause problems.  With the edges done; easier slid and you can also add a handle to grab the racks.  Just my opinion.

Keep Smokin!

Danny


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## crankybuzzard

KC5TPY said:


> Hello.  Will it hold, won't it hold?  I think you should be fine.  BUT!  If I were doing the project I would weld 3/8" bar around the edges and across the middle.  It does not need to be welded in every place.  Skip weld it.  Rough edges on expanded metal can hang up and cause problems.  With the edges done; easier slid and you can also add a handle to grab the racks.  Just my opinion.
> 
> Keep Smokin!
> 
> Danny


What Danny said for sure!


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## dookie

I would have the racks welded to an Angle Iron frame, looks clean








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## kc5tpy

Hello.  Can't beat that angle iron look!  Little more expensive but looks GREAT!  Keep Smokin!

Danny


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## weev

I know this was 20 days ago but I don't believe home Depot or Lowe's sells black iron pipe that big  it might be the black stove pipe he is asking about


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## meatsweats86

Thanks for all the input guys. I had a friend who had a 4" x 18" piece of stainless pipe laying around at his shop. I showed him what I wanted and told him the flange had to be stainless. Well..... he finished it, but he thinks the square flange might have been a piece of galvanized. Should I cut the end off and try to have someone weld on something other than galvanized, can I put a wire wheel to it in hopes of removing the zinc coating or is it safe to use like this.

The square flange will mount to the top inside of my smoker.













Exhaust.jpg



__ meatsweats86
__ Nov 18, 2016






-MeatSweats


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## daveomak

This is the page and the metal you want....  It is not galvanized on this page....   it says....    Unlike cold rolled steel, Hot Rolled Steel has a rougher surface* and with *galvanization, it can resist corrosion well.

Sooo, if you get the galvanized, which is listed in the left column, it will be galvanized.....

http://www.onlinemetals.com/merchant.cfm?id=839&step=2&top_cat=849


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