Clarke pro90 weld quality

[stamfordmini]

Hi all, a problem has developed over the last few days where the weld quality has become very poor and a lot of splatter during welding. It would seem to be a lack of power, poor earth continuity or something similar. Have checked all the connections and cleaned / replaced tip on the torch. Wire feed seems as normal and gas flow too. Thinking perhaps the earth clamp / lead may be at fault? any suggestions gratefully received, TIA

 

[Lawnmowerboy]

hi what type of earth clamp do you have, if its the clarke one, bin it and get a decent alligater one, i would have thought gas flow could be an issue if you say its splattery and unstable

 

[steveo3002]

yeah std earth clamp is poor and well worth replacing , also make sure the extesnsion lead or wiring is up to spec

 

[stamfordmini]

Thanks Guys, it is the standard clarke clamp and tried gripping it with molegrips as well. As said it's not the best quality anyway. will try a new clamp and going to check the lead with a meter and look at the mains input too.

 

[philsmin]

I replaced the cable and clamp for a thicker one on my 90EN, best thing I ever did tbh

 

[Nomad]

I replaced the cable and clamp for a thicker one on my 90EN, best thing I ever did tbh

Same here, fitted a cable and clamp from a scrap set of heavy-duty car jump leads - makes life a LOT easier than trying to use the original tinplate earth clamp.
My Pro-90 was bought new and is still very clean, the clamp has been a weak poiint from new

 

[steveo3002]

what spec cable would you buy for one...ive only done the clamp

 

[keith19]

For earth cable, something like this:
http://www.thewelderswarehouse.com/Welding/25mm__Welding_Cable.html

Like Nomad, I replaced my standard Clarke 151EN earth cable with an old HD commercial jump lead and clamp. Filed down the clamp jaws a bit flatter to grip the work nicely over a larger contact area. Very strong spring on the clamp makes for excellent contact, too.

 

[steveo3002]

whats the connection like at the end on the machine

 

[stamfordmini]

whats the connection like at the end on the machine

It is a crimped sleeve directly onto the choke conductor.

Tried a heavy duty jump lead and clamp to bypass the standard setup, no Joy

tested the rectifier pack with a DVM, all diodes open circuit 1 way and 0.512 Ohms the other way. (I understand this to be correct).

Measured the voltage between the earth clamp and the wire at the tip, results as follows:

setting 1 MIN = 19.4V
setting 2 MIN = 21.4V
setting 1 MAX = 24.4V
Setting 2 MAX = 28.4V

All connections are clean and tight.

Gas is Adams Green large bottle, 93% Argon, 2% Oxygen and 5% CO2
Dual gauge regulator set a 10 Ltrs a min.

noticed this in the manual

When this occurs, the ON/OFF switch will glow (amber). Allow the welder to cool,
until the amber light extinguishes before resuming.

The rocker on / off switch glows amber all the time. could be the overload protection has partly kicked in?