Aluminum settings help please.

[jmpgino]

I have a Dynasty 200 DX not welded up any aluminum for years. So would someone familiar with this machine please give me some settings for this small project.
I have a piece of 1/4 inch thick by 3/4 inch bar stock that I am bending into a U shape. I want to weld the two ends onto a 1 1/2 inch by 1/8 inch right angle bar.
I suppose it is going to be more tacking it on than true welding.
So tungsten thickness and machine settings would be very kind of someone.

To give you an idea of what I am doing, here goes.
We have an Airstream Travel Trailer, the double beds mattress sits on a large hinged plywood base that lifts up to access storage underneath. The mature slides around and especially moves away from the wall, this makes walking around the bed in the night difficult. So I am making this aluminum 4 inch high and 24 inch long set up, to attach to the plywood base to stop the mattress from sliding off its base.
Thank you for bothering to help me.
Cheers,
James.

[Noel]

Well James, I don't own a Dynasty 200DX so I'm not going to be much help to your specific needs. I can tell you this much, welding Aluminum hasn't changed. If you did it before you can do it again.
Maybe you need to give it the ol college try and post your attempt at doing? If nothing else we can critique from there?

[ryanjones2150]

An airstream eh? Well, James, post up a picture, I like them things....

So you're welding some fairly heavy stuff to some lighter stuff.

Here's what I do with anything in the 1/4" or higher range....

Biggest tungsten I have is 1/8", so I use that. Sharpen to a blunt point, then ball the end before you start. If you don't, at that high of amperage it'll get these little nodules and get wonky. I generally like a regular cup for this too, otherwise you'll use a lot of gas. You'll need to have the post flow set pretty long too or your tungsten will get black after a weld and make you sad. I like the balance around 60%EN and the frequency down to 50hz. The low freq will help you puddle the heavy stuff faster. Max the amps and focus your arc on the heavy stuff, keep the filler out of the way until you can puddle both pieces equally. Then ram jam and you'll be done before you know it.

[jmpgino]

Phoned up Miller and got the help I needed, should have done that in the first place. Job just finished, as usual the setting up takes ten times the time it takes to complete the welds.

[Ltbadd]

Since you did post asking for assistance, how about sharing the settings Miller gave you and also a pic or 2 of the finished part.