| I'm not a welder but seems like I remember galvy being difficult (read impossible)to weld. Also seems like a 16 foot length would be a little more difficult ot obtain. I think the home improvments stores usually only carry 10 foot lengths. A steel shop should have some sort of stock that'll work and they prolly could thread the top end for receiving an elbow to eliminate the welding. Wouldn't go with plain steel due to environmental reasons (rust). A good paint might help there though. Also if this is for sliding, threaded unions for connection would prolly remove chunks of flesh each time down. I'd think you'd want a continuous piece of something sturdy and smooth (welds even when ground smmoth would be rough and this would also be hard to achieve on a round pipe). On that note the galvining process sometimes leaves surface imperfections that could slice flesh too, not so much on OD of pipe but on dipped items I've handled before seems there were little points and protrusions from the dipping process on edges and such. Most of the fire poles I've seen are brass but I'm not sure how it would weather. I would think it would require care since the copper content would cause a patina. a steel shop should have all kinds of stock that would work. I'd think you'd want about 1.5" not for strength but for ergonomic reasons. anything smaller might be hard to grab depending on how big your kid's hands are....maybe smaller would be the way to go if it doesn't bow. Not trying to be crass, but you may want to look into a "stripper pole". They would be smooth, similar length, and obviously the right strength. Could be a cheaper alternative to a custom stainless rod from a welder's supply house. | 
