My first semi big project.

admin

My buddy want's me to weld up all his Stanchion on his commercial fishing boat. they are the part that holds up the railing. (I just learned a new word.) they were previously made out of steel and have been rusting since.  He would like the new ones made out of aluminum. Since I'm new to alloys , what type would be the best for this project?  what thickness and diameter do I need?  I will be using a miller syncrowave 250 DX. thanks
Reply:Ask a yacht  or  Sailboat hardware store , they oughta  know . Just ask on the phone .[SIZE="5"Yardbird"
Reply:Schedule 40 pipe is what they use on sportboat towers, not sure of the exact alloy. Why not 316 stainless?Reference:Aluminum - http://www.saltwaterspecialties.com/Stainless - http://www.houseofstainless.com/home.htmLast edited by tanglediver; 02-11-2008 at 10:39 PM.City of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:Originally Posted by tanglediverSchedule 40 pipe is what they use on sportboat towers, not sure of the exact alloy. Why not 316 stainless?
Reply:Seems to me 2 reasons for Aluminum . ONE is it's 1/2 the weight . that also means it's about 1/2 the cost ,since it's similar in cost/pound . I'd say they like cheaper, & they like less weight up high , so that it has a lower center of gravity .  That make sense ?Last edited by Roy Hodges; 02-11-2008 at 10:48 PM.Reason: spelling[SIZE="5"Yardbird"
Reply:If you call an aluminum suply house they will probably tell you what they always tell me "5356 is marine grade" I use 5356 or 6061. If you wax the aluminum with a good wax every 6 monts it will help it last. I would recomend 316 even with the cost. I live on St. Thomas and work on boats all the time and aluminum just does not hold up like 316 in a salt enviornment. If you hit a dock with aluminum it will crack were 316 will usually bend. Last week I fixed a davit (the thing that holds a small boat on the back of a big boat) on a sail boat from Tabago it was 316 and it was 20 years old and looked like new. I told the guy I was woried that a new davit would have a broken so soon and he said well 20 years one break a gazillion miles not bad. I agreed. I get my aluminum from OC Aluminum in TX super cheap and great to work with. I orderd 9500' of tubing and had it in 14 days. TX to St. Thomas I was happy. Steel Thunder Welding LLC. St. Thomas VI USAMM350PBOBCAT 3MAXSTAR 150 STH375 EXTREME PLASMA6.5 HP COMPRESORDEWALT 18, 24, AND 36 VOLTO/A TORCH SETAND SO MUCH MORE I DONT REMEMBERALL IN MY 2005 2500HD EXTENDED CAB L/B