I mentor a high school robotics club in the San Francisco bay area and we are looking for a welder who could provide us some instruction on how to weld aluminum tubing using a mig welder. We can stick two pieces together but it's not pretty or strong. Please PM me for more information. Kelly
clean the surfaces thoroughly with a virgin stainless steel wire brush. aluminum forms a thin exterior layer of aluminum oxide which is much harder to penetrate on arc start. what is the alloy of the material being welded? need to pick a wire to match Wire diameter to match the thicknesses being welded together, gas to match the wire, correct polarity, set wire speed and and current settings starting with the base settings provided by the wire manufacturer or a reputable reference book. practice on scrap before trying the actual part. a trip to a good welding supply store can get you in the ballpark.
c02 and aluminum wire can be used on any mig welder except for gasless.I use this setup at work and on a small mig i have at home.
Where are you located? I am in hayward. I know a welding teacher that would most likely be willing to weld any aluminum you need welded for free. It will be tig welded not mig, so it will be prettier and stronger. can give you the info if you would like. thanks, Douglas Johnson "Skrach" www.VividlyVintage.com
The guy I know that does alum weldeing also cleans the surface with acetone before welding. Yes you need a spool gun to weld aluminum with a mig or a push/pull gun because the aluminum wires so soft itll kink if you try to just push it threw the liner.
You don't need a spool gun to weld aluminum, you just need a mig welder that is set up for aluminum. We weld aluminum without a spool gun in a mig welder daily. Someone must know someone to help this guy out. Maybe even talk a little car talk while teaching them to weld aluminum!!!!
We had a freshman weld the chassis for the FRC team 1726 robot this year. The trick is to be more open minded about material selection. We used thinwall steel tube and 1/8" steel angle and strap to make the chassis. Having all that weight down low means you need to make the rest of the robot light...which helps keep it from tipping over. We used thinwall aluminum tube and other lightweight materials for the top, mostly riveted together. the kids painted the chassis silver....and they swear it wasn't to try to make it look like aluminum. boy, is this off topic!
Thanks for all the replies, the team I'm working with has been participating in the FIRST events for over 10 years. We are currently using a Hobart 140 Mig, w/o a spool gun. We are generally welding 6061 series 1/8" wall, we are using .035 wire as we cannot push .030 wire through the machine without creating a birds nest. We prep the joints using a ss wire brush and pre-heat the joint with a propane torch, but our welds still look like crap. Squirrel, I'm with you, this summer we're going to build a frame out of thin wall steel tube this summer to show that it will be just as light or lighter than the aluminum frames we have been making.
Don't expect the steel frame to be lighter than the aluminum frame...but do expect it to be easier to weld together. You need to manage weight well if you do this, we ended up with a 113 lb robot this year, because we knew we had to make the ball pickup, shooter, etc as light as possible. All the hep cats use TIG to build their chassis with aluminum. Or if you want to get fancy, do it like 1501 (and 4183 my brother's team) and rivet sheet aluminum together.
Here in my county (in Georgia) I used to sponser FIRST, BEST, FLL and F1 in Schools. We have been told that there will be NO welding happening even with flux-core crap because it is too dangerous. I have also been told (after having 3 nationally ranked teams at the middle school level in F1 in Schools, that the concepts are too difficult for kids) Needless to say, after 7 years teaching, I am done. This is my final year. I commend you for doing this and let me know if there is anything I can do to support you out there.