Info about HF MIG 170 and MIG 180

[W6PUG]

I have a 180, and was prepared for some disappointments, but thus far it has surprised me favorably, except being able to get spare parts for it, BUT, with some perseverence, I have dug up the following info, which might help someone out there:
HF MIG170 and MIG 180 does not have spare parts for the MIG gun. The gas nozzle is threaded at the base.
Lincoln part number KH725 gas nozzle fits perfectly ($8) and
Lincoln KH726 Flux Core nozzle ($4), also a perfect fit, is really nice for you guys who do mostly FCAW (like me). These parts are readily available at Home Depot.
The current settings and duty cycles are not in the manual but here is what I found out:
Switch Setting/ Current Value / Duty Cycle%
A. 30A 100%
B. 45A 100%
C. 70A 86%
D. 95A 47%
E. 120A 29%
F. 145A 20%
These are based on tap calculations which is a little understated, because real current and voltage has variables of wire size, length from tip to work and all of that, but this is somewhere to start.
NOTE: 180A RATING IS THE MAXIMUM OBTAINABLE CURRENT BUT 140A IS THE ACTUAL CURRENT WHEN USED AT THE 20% DUTY CYCLE.
Hope this helps! Doug W6PUG
1944 Hardinge TL lathe
Aciera F2 mill
HF MIG180 welder
Longevity D40 plasma cutter
Floor drill press, compressor, stand grinder, chop saw and "all that kinda stuff"

 

[xman_charl]

Been using 180 for several months now. Has cap mod. Older 171 mig was given to member
of my church.

Somewhat satisfied with 180. Get those new Lincolns, much better mig.

Photo of mig 180 weld, switch position F.

Charl

 

[W6PUG]

I did not realize when I got it that HF welders are all AC / my welds are strong and my puddle patterns are good but cannot get that finish look I used to get, and then found out that HF welders are not DC ... my fault for not recognizing it when I got it. I will investigate putting the cap and bleeder resistor in and seeing if that helps, but I gotta feeling I will probably be looking at another welder before long. It is doing the job ... live and learn :nuts:

 

[jlrice54]

Actually the Harbor Freight MIG sets that are gas or flux core (131, 151, 170, 180) are all DC welders. If you are getting AC output, your rectifier board is bad. The DC output is very choppy and the cap mod will smooth it out. Also putting the wire feed board on it's own rectifier will smooth out the feed pulsations that these machines inherently have. Adding the cap/bleeder resistor modification and smoothing out the wire feed rate with the separate rectifier/capacitor mod will make the HF welders produce welds as good as most of the big name welders produce. Check out what is being done with the HF MIG welders on Welding Web forum.

I'm not sure what the flux wire only models have as I've never looked in to their schematics.

James in NTX

I did not realize when I got it that HF welders are all AC / my welds are strong and my puddle patterns are good but cannot get that finish look I used to get, and then found out that HF welders are not DC ... my fault for not recognizing it when I got it. I will investigate putting the cap and bleeder resistor in and seeing if that helps, but I gotta feeling I will probably be looking at another welder before long. It is doing the job ... live and learn :nuts: