wolf welder on e-bay

[gavuk]

anyone after a cheap welder? read this owners comments
http://cgi.ebay.co.uk/Business-Offi...rkparms=72:12|39:1|65:12&_trksid=p3286.c0.m14

 

[shenion]

At least the seller is honest that it never worked.

They don't even work right when new.

 

[Rich.C]

A live torch, must be a nasty bit of kit to use

 

[shenion]

A live torch, must be a nasty bit of kit to use

Add to that no reactor so the welds will not have proper fusion or penetration and spatter like crazy. Also no filtering so expect your VCR to start flashing 12:00

 

[gavuk]

hi shenion,i thought the owner was incredibly honest,and thought i would post advert as someone had discussed wolf welders on another thread,and were told they were rubbish,but can you explain "no reactor" ?not sure i've heard that term in relation to a welder,and if i have i've definitely forgotten what it means.........many thanks

 

[shenion]

The reactor is an inductor placed in series with one of the weld leads. It has a significant effect on the duty cycle of short-ard MIG welding.

Basically, when the wire touches the weld pool it creates a short. With no reactor the current will rise real fast and vaporize the end of the wire. Then the current quickly drops to 0. This results in short current pulses and the wire builds up with little fusion. The average current is small as the duty cycle is low.

The reactor smooths out the current reducing the peak and increasing the time the wire is in contact with the weld pool. It also stores energy while the drop of metal melts off the end of the wire. Then the reactor will maintain the arc across the gap. This adds heat to the weld pool and flattens out the weld and increase fusion. It also helps maintain an arc between the rectified AC power cycles.

Someone posted pics here of a Wolf schematic. Had no reactor. It probably relied on the fact that it also had no filtering on the rectifier and used the main transformer inductance.

Junk. They may have reactors in some, but I doubt the cheap ones

 

[weldequip]

Junk.

You hit the nail right on the head Shenion!
weldequip

 

[gavuk]

thanks for the explanation shenion ,understand a little bit more about the process now from your very clear description,(u must have realised i'm a fitter.),out of intrest ,can duty cycle be increased with fan upgrades to cheaper welders?like overclocking computers ?more airflow=cooler=increased duty cycle?or are there other factors that come into play?

 

[peterd51]

Hi,

I did that with a Clarke Pro 90 some years ago. The only difference between the 90 and their Pro 100 was the cooling fan.

It worked OK when patching up cars, etc, as I'd cut a plate, weld it on then switch off and cut another but the cooling fan was still running.

I doubt it'd work well if you're looking at welding non-stop for long periods.

Regards
Peter