|
Posted by Grant Erwin on August 7, 2007, 7:04 pm
Please log in for more thread options
John Husvar wrote:
> Putting the final welds on a 28 X 26 12 ga. SS plate, nicely curved to a
> consistent radius, and which cost no few pennies. Everything was going
> well. I had 25 small 1/2" X 1/2" posts holding the plate to its mild
> steel frame. The 309L joined the metals with ease and panache and the
> whole thing was looking pretty nice.
>
> And then the Eau Chitte moment arrived. John, the Dipstick, (that would
> be Your Respectful Author) welded the center supports first, then got
> truly stupid and welded the outer supports next, neglecting the
> intermediate ones, then went back and tried to weld those intermediate
> posts.
>
> And I said to myself, too darned late: Now, Self, what the Liver-Loving
> Hell did you think was going to happen when you make a weld equidistant
> between two completed ones on the same curved line? Yep, they pulled and
> made three of the prettiest bubble bumps you ever saw. That 12 ga. SS
> pulled down around the posts quite prettily, if you like expensive
> vertical fornications.:)
>
> Never occurred to me until too late that welding the center and ends
> introduced stress into the plate, which promptly relieved itself when
> the plate around the intermediate posts got to welding heat.
>
> Might, _might_, have got away with it with TIG, but OA wasn't so
> forgiving. Too large a HAZ, apparently. Too dumb a welder, certainly.
>
> What started out to be a form for heat bending HDPE for custom
> wheelchair seating backs is now a rather nice looking, but useless objet
> d' junque.
>
> Damn! :)
>
> Oh, well, off to buy another bent plate and start over. That $2000 entry
> fee for getting into TIG welding is looking cheaper and cheaper.
>
> (Although that might have made little difference, considering the
> screwup by the Party of the First Part.:)
I was taught that stainless has much more distortion issues than regular
steel. I don't know what the solution to your problem would have been,
maybe some kind of preloading before welding.
I hate those eau chitte moments.
GWE
| 
Yahoo! 
Google 
Windows Live 
del.icio.us 
digg 
Netscape 
XML Sitemap
> consistent radius, and which cost no few pennies. Everything was going
> well. I had 25 small 1/2" X 1/2" posts holding the plate to its mild
> steel frame. The 309L joined the metals with ease and panache and the
> whole thing was looking pretty nice.
>
> And then the Eau Chitte moment arrived. John, the Dipstick, (that would
> be Your Respectful Author) welded the center supports first, then got
> truly stupid and welded the outer supports next, neglecting the
> intermediate ones, then went back and tried to weld those intermediate
> posts.
>
> And I said to myself, too darned late: Now, Self, what the Liver-Loving
> Hell did you think was going to happen when you make a weld equidistant
> between two completed ones on the same curved line? Yep, they pulled and
> made three of the prettiest bubble bumps you ever saw. That 12 ga. SS
> pulled down around the posts quite prettily, if you like expensive
> vertical fornications.:)
>
> Never occurred to me until too late that welding the center and ends
> introduced stress into the plate, which promptly relieved itself when
> the plate around the intermediate posts got to welding heat.
>
> Might, _might_, have got away with it with TIG, but OA wasn't so
> forgiving. Too large a HAZ, apparently. Too dumb a welder, certainly.
>
> What started out to be a form for heat bending HDPE for custom
> wheelchair seating backs is now a rather nice looking, but useless objet
> d' junque.
>
> Damn! :)
>
> Oh, well, off to buy another bent plate and start over. That $2000 entry
> fee for getting into TIG welding is looking cheaper and cheaper.
>
> (Although that might have made little difference, considering the
> screwup by the Party of the First Part.:)