Clarke 130EN and Aluminum

[shenion]

Been practicing with my 130EN. Thanks for the wire speed vid, I found I was using too low a speed.

I did not realize you could do aluminum with MIG, was under the impression that you HAD to have a TIG.

Been playing with aluminum welding. I can do thin sheets well. Seems it absorbs the heat well. Been trying 3mm stock and the wire just melts back to the tip on the lowest current setting. Really wish the 130 went down to 20A. My power here is 125V instead of "110", so currents tend to be a bit higher.

With steel and lowest current, my speed is set to about 4-5. With Al I need to have it about 8 to keep it from melting back to the tip.

I did find increasing the gas flow (Argon) to about 16LPM helped the wire melt-back issue, but the weld is then tall and a bit cold.

I have been fighting birdsnesting/feed with the 0.30 wire. The tension screw is almost completely loose. Been using an 0.35 tip.

I have some questions:

1. I checked a source here and they have a Nylon-liner (requires and adapter?) I think this will help feed, but the liner says "0.35 Aluminium wire" Can I use it with steel wire? Maybe it would wear out the liner. The 130 has a fixed lead, so I can't plug in different cables when switching between Al/Steel.

2. I think moving to 0.035 wire (0.9mm) will help feed and the wire burnback and penetration.

3. I assume I would use an 0.045 tip for 0.35 Al. Cant seem to find them locally.

I'm tempted to make a nylon wedge to fit between the rollers and feed tube, or at least grinding the end of the tube to a V and getting it closer to the rollers.

Of course, a spool gun would probably be best, but these cost more than the welder itself.

Thanks to this site, I can do decent welds with steel. If I can add Al to my bag of tricks I can fab some custom mufflers for my R/C planes (most have chain-saw engines.) I could also do some repairs for "Sudden overdose of ground"

 

[malcolm]

Planes with chainsaw engines? They must be enormous - would love to see pics or a link.

Sounds like you are on the right track with aluminium. I found the power settings similar to steel but the wire speed about double when I was using a heat sink. Teflon wire is recommended for aluminium but a nylon liner would certainly be better than steel and reduce the birds nesting. You can cut the end of the plastic wires into a V to get it really close to the rollers. Nylon liners last well with steel wire, though I've never tried a teflon one.

If you have fine drill bits you could drill out the tip. I drilled out a 0.8mm tip to 1.0mm for aluminium. A tip designed for 0.045 steel wire should be perfect for 0.035 aluminium wire. Thicker wire sounds like a good idea to reduce wire speed and make it easier to feed.

You'll probably find it difficult to weld thinner aluminium, though with a heat sink it might be possible.

 

[shenion]

Planes with chainsaw engines? They must be enormous - would love to see pics or a link.

Most are 1/4 scale with 5-6' wingspan. Largest is 88" with 62cc chainsaw engine.

http://shdesigns.org/planes/

Missing on the site is my 1/4 scale Cristen Eagle biplane. 50CC Poulan chainsaw engine: http://www.greatplanes.com/airplanes/gpma1217.html

Sounds like you are on the right track with aluminium. I found the power settings similar to steel but the wire speed about double when I was using a heat sink. Teflon wire is recommended for aluminium but a nylon liner would certainly be better than steel and reduce the birds nesting. You can cut the end of the plastic wires into a V to get it really close to the rollers. Nylon liners last well with steel wire, though I've never tried a teflon one.

Thanks, don't want to have to reassemble gun/roller assembly every time i switch.

If you have fine drill bits you could drill out the tip. I drilled out a 0.8mm tip to 1.0mm for aluminium. A tip designed for 0.045 steel wire should be perfect for 0.035 aluminium wire. Thicker wire sounds like a good idea to reduce wire speed and make it easier to feed.

You'll probably find it difficult to weld thinner aluminium, though with a heat sink it might be possible.

I have already drilled out tips. The local home supply never has them in stock. So took a 0.030 tip and drilled to 0.041.

Thin metal should be ok with 0.030 wire. Most of the heat goes into the metal, you just have to keep you speed up and welds tend to be flat. I have AlumiWeld rods that work well on small stuff. Great for stripped out threads. Fill with rod and then drill/retap. But its melting temp is near that of Al. So it can be tricky not destroying things. It also has no gas shielding so you have to stir the weld pool to break through the oxidation.

Did some searching of Al/Mig. One site had good tips and said "Forget using 0.030 wire."