Galvanized gives no benefit. However.the tiny mount of zinc oxide produced would be no problem . I would suggest a local weld shop may have some stock to make you something. Material at least 1/8" ( 3 mm) thick if you want it to last awhile. Stainless steel is pretty common, either the magnetic ( like auto exhaust) or non-magnetic. Stainless would not need to be as thick. Try a local junk yard.Bolts would be much more practical than trying to rivet. If you could find it, short length cut from large pipe like 24" diameter. Or , the old stand-by, 55 gal drum , cut off a foot of drum.
Answer from blacksmith37 on Stack ExchangeLooking for some assistance on proper materials and execution. My family owns property where we have a cabin. We currently have a fire pit, but it doesn’t have a ring or stones around it. It’s just an area in the ground about 3 feet in diameter, some brick/stone (yes, the kind that withstands the heat) to demarcate the area. I was looking to get them a ring about 5-6 feet in diameter, but they’re fairly expensive. Any thoughts on how I can make one, buy the materials and have someone do it, or should I just pay the full price and have it made for me? Thanks!
Photo from Fire Pit Screens to depict what I’m describing.
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Galvanized gives no benefit. However.the tiny mount of zinc oxide produced would be no problem . I would suggest a local weld shop may have some stock to make you something. Material at least 1/8" ( 3 mm) thick if you want it to last awhile. Stainless steel is pretty common, either the magnetic ( like auto exhaust) or non-magnetic. Stainless would not need to be as thick. Try a local junk yard.Bolts would be much more practical than trying to rivet. If you could find it, short length cut from large pipe like 24" diameter. Or , the old stand-by, 55 gal drum , cut off a foot of drum.
I answered your question. 1 Steel is a better choice than galvanized for the reason you gave. 2 A weld is preferred to bolts. What is it you need help with cutting steel or, using a drill bit? Making a circle is easy. You also need fire rated paint if you don't want rust. I also gave other options, including purchase of one, that will not rust for a long time. It also has no risk of fumes. Grass removal is also key. I guess you need to be more specific.
(edit Most barrels...) won't last very long as fire pits. I know this from burning trash when I was a kid. By the time the barrel was full it was falling apart. I never counted, but I would expect it to work well for about 10-20 burns and maybe 50-60 burns before its paper thin and falling apart.
Edit: The thickness of the metal is what matters. 18 gauge drums are what I find to be the industry standard; 18 gauge won't last very long in my opinion. A thicker drum would last longer. I personally own a fire pit object that is very thin, which probably would not last more than 10 burns. So it goes to show that any ol' manufacturer may not necessarily make a decent product.
I have seen barrels converted to wood stoves. I have seen some of them fall apart and I have seen some stand for decades. This is due (primarily) to the thickness of the steel.
Edit2: Product reviews are probably important when you can't get the actual specifications. Amazon has reviews for the example product that you linked... 3.5 stars is not so hot.
"what (are) the advantages of having one..." "to avoid direct heating of the surrounding rock/concrete"
Yes, the advantage is to reduce direct conductive and radiant heat transfer to the surrounding material. Heating clay bricks, rocks, stones, concrete, decorative bricks/pavers, etc. will cause them to crack and crumble. Sometimes immediately, sometimes over a period of time. Sometimes explosively and dangerously, due to moisture in the stone/clay/concrete (unless you use special refractory brick).
I agree with other comments and posts, a DIY job is fine but thicker steel/iron is the key to good performance. I would say 12 gauge would be minimum thickness.
I’m planning on building a fire pit out of retaining wall blocks. I’ve seen it done before and I seen people with rings in the middle and without. Is it necessary?