<HTML><FONT FACE=arial,helvetica><FONT SIZE=2>This is interesting. Can it also happen from the heat of machining it?
<BR>Paul
<BR>#23 Ashwagh
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<BR>In a message dated 3/28/02 6:47:01 PM Eastern Standard Time, chrishardy@tds.net writes:
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<BR><BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px">Subj:<B>Re: [Alberg30] aluminum 6061 t-6</B>
<BR>Date:3/28/02 6:47:01 PM Eastern Standard Time
<BR>From: chrishardy@tds.net (chrishardy)
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<BR>Ran across this at Brion Toss's rigging page I'm In the process of welding up a radar mast for the aft deck of #296 I thought somebody may be interested with all the talk of aluminum alloys....
<BR></FONT><FONT COLOR="#660000" SIZE=2 FAMILY="SANSSERIF" FACE="Arial" LANG="0">: "I am considering making a welded aluminum spar,out of 4'x 12' 6061 T6 plate. The boat I am building is a 34' aluminum cutter that will displace 14000 pounds. I have used the Riggers Apprentice to figure the moments of inertia and found a stock section that fits, now I would like to build a octagon with longer sides that closely matches those dimensions. If you have any advise, reasons why I shouldn't build it or know were I could read more on this I would appreciate it. thanks Paul</FONT><FONT COLOR="#000000" SIZE=2 FAMILY="SANSSERIF" FACE="Arial" LANG="0">
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<BR>Paul,6061 T-6 is a tempered aluminum alloy, welding will ruin the temper. Retempering al is NOT a do it yourself project. Take a small piece of the plate and run a weld across the middle, bend it and you will notice it is very much softer in the welded area. Sorry. "</FONT><FONT COLOR="#000000" SIZE=2 FAMILY="SANSSERIF" FACE="Arial" LANG="0">
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