[Jag Daddy]

I want to take some 3.5 inch aluminum square tubing and weld it end to end to a 3.5 inch round aluminum tubing. This piece is going to be polished up. I have a couple questions, how much weld can be removed before it causes problems. Also since I'm going from square to round there will be opening at the corners of the square tubing I need to close off. What would be the best way to do this. Thanks for the help

Regards
Mark:thumbup:

 

[4 Jaw Chuck]

Flat plate on the end of the square tubing will finish your butt, TIG and lots of filler rod will give you plenty of metal to work with for polishing the weld.

 

[Jag Daddy]

Should I weld the flat plate then open the hole between the tubes? The part is not going to have to handle more than a few pounds of weight so I guess I can grind away more of the weld than if it were going to be a heave duty part. My other option was to try and turn the part on a lathe out of a square block. But boring a 3 inch hole seemed a bit much.

Regards
Mark:thumbup:

 

[adtkart]

Since I don't know what it is that you are trying to make this may not help, but. You could try forming the round tubing into a square to better fit in the square tubing. That would require less filling and grinding to pollish up. You could do this by taping a tapered square piece into the round tubing. Typical square into round hole type of deal. May need a large hammer! If you take it slow and tap on the sides of the tubing while forcing in the tapered part, you may be able to get an almost perfect fit. Surely perfect enough for welding.