Hobart 210 Running Aluminum without Spool Gun

[TMGT]

Not 100% right. The contact tip does transfer some amperage but the liner does as well and why the liner MUST be securely clamped into the receptacle in the welder. as the wire travels thiugh the liner it gets receives amperage all along the way...

Been doing this stuff for decades.

The primary reason why tips are copper alloy is so hot spatter don't stick to the tip readily. It does to some extent as well as inside the nozzle and why I always start out spraying anti spatter coating in the nozzle as well as on the tip. I use Radnor anti spatter in a spray can myself, but some like nozzle dip, I don't and I clean both the tip as well as the nozzle regularly with MIG pliers and reapply the anti spatter after cleaning and with any nozzle or tip, they are consumables and have to be replaced after a time.

Not entirely true, while a metal liner may transfer some current to the wire, the contact tip can be the only transfer area.

We run full nylon liners on a few welders for aluminum where there is no metal contact until the contact tip, trust me, you don't want much current transfer through the liner as it can lead to arcing and failure.

 

[5030]

I don't and never have and don't plan to.

 

[TMGT]

One more thing. My neighbor is the weld expert. He occasionally borrows my spool gun. When I first ordered some aluminum wire he said to get the 4000 series wire for general purpose welding. TaDa

The 4043 is a preferred wire for most general welding on 4, 5 and 6000 series aluminum as long as it's not getting anodized or has a higher strength requirement.

5356 is another common wire for anodized, it doesn't flow as well and is typically is a little stronger/harder. It will also feed better if you don't have a spool gun or push pull, but for general welding if stick with 4043, you'll just have to be real careful how you manipulate the gun and keeping it straight.

I really prefer lincolns superglaze myself.

 

[mrmikey]

Do keep in mind that the liner itself transfers the amperage to the wire and not the tip

Don't think so.
I've run .035 5356 and 4043 wire with my Thermal Arc 181i and I used a teflon liner as the original steel one would stick every now and then. If you cut the whip apart you'll see the main power lead goes to the torch body and from there to the contact tip, any voltage/current in the liner is coming from the connection of the welding wire to the contact tube back thru the liner.
The 5356 fed better as it's a stiffer wire, you'd still get the occasional birds nest but all in all it worked pretty good. Keeping the lead as straight as possible would help a lot too as well as not tightening the crap put of the feed rolls. I'd also use the next size up contact tube with mixed results but it helped when welding fairley steady as the tip would get hot and the alum wire would gall to the inside of the tip.
One of the salesmen had said that he would cut 1/2 the side off the contact tube for about 1/2 the length so it was like a trough and wide open. Seemed to help a bit.
If you're using a smaller machine with limited 'oomph' as mine is, grinding the oxidization off the area you're welding will help with establishing the arc as you don't have to burn thru it to establish the arc. If you don't you'll find you're stubbing out a lot with burnback.

 

[5030]

Neither of my Hobarts are like that at all. The liner fits into the socket on the welders and is secured with a thumb screw, there is no other means of transmitting amperage but the liner itself and the tip but the wire contacts the liner physically as it moves through it. Went out in the shop (even though it's Sunday) and pulled the tip entirely and viola, the wire was hot.

Your mileaage may differ but I know what mine is... Never used a liner with an insert in it and I've never had an issue with the wire, ever. Of course I run quality wires and we run a lot. I buy my wire by the case.

 

[mrmikey]

That is a different setup than I've ever seen for sure, learn sumpin' ne every day . You wouldn't think the small coiled wire would be able to carry any amount of current as it's not a heck of a lot larger than the wire you're welding with.

 

[diesel85]

Neither of my Hobarts are like that at all. The liner fits into the socket on the welders and is secured with a thumb screw, there is no other means of transmitting amperage but the liner itself and the tip but the wire contacts the liner physically as it moves through it. Went out in the shop (even though it's Sunday) and pulled the tip entirely and viola, the wire was hot.

Your mileaage may differ but I know what mine is... Never used a liner with an insert in it and I've never had an issue with the wire, ever. Of course I run quality wires and we run a lot. I buy my wire by the case.

That is how my Hobart 210 is. Just held in by a thumb screw. Judging by how the liner/feed hose is connected, I could see how this works. I always felt like the nozzle tip was to add to the conductivity and to help feed the wire straight and prevent slag from entering the liner/gun.

 

[diesel85]

That is a different setup than I've ever seen for sure, learn sumpin' ne every day . You wouldn't think the small coiled wire would be able to carry any amount of current as it's not a heck of a lot larger than the wire you're welding with.

I learn new things every so often on a project. Even the best sharpen their skills by doing the trade. That is how you get better.

To be honest, with all of the time I've put behind welding, I feel like I only got about a year or two of welding under my belt. Because I don't do it everyday. So I am still green at it. And I never went to school for it.

I also learned a long time ago, a grinder is no substitute for a good, clean, penetrating weld.

 

[TMGT]

Neither of my Hobarts are like that at all. The liner fits into the socket on the welders and is secured with a thumb screw, there is no other means of transmitting amperage but the liner itself and the tip but the wire contacts the liner physically as it moves through it. Went out in the shop (even though it's Sunday) and pulled the tip entirely and viola, the wire was hot.

Your mileaage may differ but I know what mine is... Never used a liner with an insert in it and I've never had an issue with the wire, ever. Of course I run quality wires and we run a lot. I buy my wire by the case.

The nylon liners are for aluminum, the only machine I know of off the top of my head that uses a metal liner for aluminum is Fronius (excellent machines by the way).

Yes the liner can transfer current, but try to strike an arc and you'll quickly be replacing the liner as the wire will arc off of it and cause damage.

There's a reason it's called a Contact tip!

 

[mrmikey]

Because I don't do it everyday. So I am still green at it. And I never went to school for it.
I also learned a long time ago, a grinder is no substitute for a good, clean, penetrating weld.

I graduated welding trade school when I was 18, 51 years ago...crap, it seems a lot longer when you actually see the numbers in print LOL.
As for grinder, that and a can of paint are a weldors best friend .