OK, I know nothing about welding except that it makes two pieces of metal stick together. So, can you weld steel to alum.?

Dont hurt me too bad. Just exploring some options for having horizontal drops put on my alum. hardtail frame.

thanks.

No. In almost all cases you cannot weld disimilar metals. Some metals can be brazed or soldered together. This where you use a third metal that will "bond" to both of the other metals and even in this case you are most often bonding two of the same metal to each other but you need a low temp so as not to damage anything.

Alluminum dropouts can be purchased or made and welded in by a competent weldor.

Thats what I thought. Thank you reverend. Do you know of an online retailer that sells such alum. dropouts?

www.framebuilding.com for all your frame building needs They have loads of steel lugs, braze-ons and tubes, and a good selection of aluminum, titanium and carbon parts too.

In the field of welding as it applies bonding dissimilar alloys hsa been done with limited testing in the automotive field. Using a process called MPW or magnetic pulse welding alu. and steel aloys have been bonded. However given the low temperature of alu alloys in most cases (1250 F) to melt as opposed to alot of steel alloys including stainless which is much higher. A tig weld would most likely fail and you would be scraping the alu. off the floor.

Welding? Call the fire department if I get near a welder!

I believe some aluminum alloys can not be welded. I think it is the 7000 series.

In a word... NO.

There are many frames built from welded 7000 series alloy.

I just check lincoln electric's webpage. Some 7000 series can be welded and some can't. Also some of the 2000 series can not be welded either.

I said there are many frames BUILT with 7000 series alloy in specific 7005 which there have been millions of frames welded. Most of the time it is either 6061 or 7005 series alu alloy. Most of your 2000 series in specific 2014 is cold forged one piece components like handlebars, and stems.