I'm in a hurry so I'll try and make this quick,
St69 you're old frame and new one are both gal. steel.
In a perfect world stainless would be great.
I haven't seen one yet I assume cost is too much.
I choose gal. steel because it's easy to work with a durable as heck.
Aluminum is used also for frames,but in order to get the same strength as steel you have to increase the diameter by .25 etc etc.after alls said and done,you 've got frame that weights only a little less,than a steel one yet cost you 50% more to build.

Rust is somethind we all live with here in the N.W .
so just like anthing else we Cat owners have to do a little maintance periodicly.

Coot:as far as you're question,I've never had a seperation on one of my frames,
If welded correctly the weld is stronger than the original material....sorry gotta run.....Os
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[/b]The less I give a [Bleeeeep!] the happier I am[/b]