Just curious to know what can be done with a crack in an aluminum frame. Is welding an option or is it just best to trash it?

Depends...

If the crack is on the joint weld then it's probably fixable - again, it depends on the nature and what joint.

If it's on the tube I recommend not riding it anymore.

Pics?

Aluminum frames are heat treated after assembly. If you weld it you remove the heat treating in that area.

Warranty?

Those smugglers get more and more inventive it seems ...

Take all the parts off the frame and hang it on a wall. Put the parts on a new frame.

What brand frame is this? How long did you own this frame/bike. Did you purchase it new?

Are you sure it's not a carbon frame?

Aluminum cracks as well. Sure you can fix it but probably will crack somewhere else at some point in the future, obviously depends where the crack is too. But yes eventually you can but who knows how long it will last before another crack shows up maybe in the surrounding area. If you need to buy some time until u get money for another one, then fix can be done... your call after all..

The issue with aluminum is that the joints (or were the weld is) get stronger than the tubing and thats why needs to be heat threaded so the whole frame gets structurally even. Thats the reason good aluminum frames are expensive, for example the cheapo stuff sure is not even heat treated

good luck.

He said "crack" not "asplode"

Depends on the alloy. 7000 series alloys may not need heat treatment after welding so could be viable to repair, but 6000 series will.

grab a cheap nashbar frame...under $100 and pretty solid.

Stick a fork in it, it's done.