Well, having a SIP has always made welding a bit of a chore. Its not THAT bad a machine, perfectly useable infact, but you have to fight a bit harder to overcome the machines weakneses rather than just concentrate on the actual welding. Wire-feed was the usual probelm.
Its a topmig 170 turbo and is a good few years old.
The drive system has a few physical problems, which I detailed my fixes of later on in this thread here....
http://www.mig-welding.co.uk/forum/showthread.php?t=3215
These arent the only problems either, electrically, the feed isnt great. Its been coverd here before, but basically its a weak motor with a poor controller, all of which takes its power from a transformer whos output varies a fair bit as the weld arc fluctuates. If I pulled the trigger with the torch in the air, the motor would turn smoothly andthe speed could be altered smoothly, but as soon as I struck an arc, I could hear the motor speed fluctuating, which was making the arc splutter, which was making the eed worse in a nasty cycle.
The solution? Bin the lot and replace it.
I am no electronics expert - far frm it infact, but this is simple enough stuff. Obviously, you do so at your own risk...
Looking at it, at max speed, the motor gets up to about 18v....thing is...I never use it anywhere near max speed even on full power. 12v would suffice, so I ordered this 12v motor controller from Maplins....
http://www.maplin.co.uk/Module.aspx?ModuleNo=30310&criteria=motor speed&doy=18m7
I unplugged the feed to the motor, and removed the original wire-feed control circuit from its mounting, leaving it taped up inside the welder. The original feed to the motor I connected to a 12v automotive relay - just a bog standard thing. With the original wire-speed knobabove 1/3 of the way round, When I pull the trigger, the relay closes.
I then fitted an old battery charger inside the casing too. Its a cheap halfords job, but gives a decent output. The negative from the charger goes straight to the -ve input on the maplins module. The positive feed goes through the relay to the module. The modules output wires go straight to the motor.
I pull the trigger, the old mire-feed controller sends 12vish to the relay, which closes, sending 12v to the maplins unit, which I mounted in the original hole on the welder.
Lastly, I piggy-backed the 240v lead for the charger to the mains switch on the welder so they switch on and off together.
And there you have it.
The maplins unit gives incredibly fine control of the wire speed, from a barely moving crawl to full speed, which is still higher than ever needed with this machine.
The seperate 12v supply means hat the motor speed is NOT affected by the welding arc, so it remains stable no matter what you do with the torch. Gone is the traditional SIP random splattering and it now sizzles perfectly.
The only downside is that I have lost the automatic step-up or step-down of the wire-speed when changing the welders power, I need to change this manually - Hardly a major hardship as I always had to fine-tune it between power settings before anyway.
Since I have had this welder, it has been a chore to use. It was possible to get good welds, but was always hit-or-miss with its consistancy, and it required very regular cleaning and tweaking to keep it useable. I found it would let me down just when I needed it to be reliable. Usually when lying on my back holding a sill panel in place with my head and feet, and trying to tack it in place and getting nothing but crappy bird-**** splatters.
Now though, its a breeze. Its reliable and consistant. In my old workplace we had a couple of top-of-the-range Sealey things, which were great, very easy to get good welds from, now I can honestly say my SIP is on a comparable level with them.
Now, im sure some boffin will come along and point out the phase rectifier electro-shimmy inducer is the wrong polarity to be compatible with the intra-electron transfading multi widget, but you know what???? IT WORKS ANYWAY!
Its a topmig 170 turbo and is a good few years old.
The drive system has a few physical problems, which I detailed my fixes of later on in this thread here....
http://www.mig-welding.co.uk/forum/showthread.php?t=3215
These arent the only problems either, electrically, the feed isnt great. Its been coverd here before, but basically its a weak motor with a poor controller, all of which takes its power from a transformer whos output varies a fair bit as the weld arc fluctuates. If I pulled the trigger with the torch in the air, the motor would turn smoothly andthe speed could be altered smoothly, but as soon as I struck an arc, I could hear the motor speed fluctuating, which was making the arc splutter, which was making the eed worse in a nasty cycle.
The solution? Bin the lot and replace it.
I am no electronics expert - far frm it infact, but this is simple enough stuff. Obviously, you do so at your own risk...
Looking at it, at max speed, the motor gets up to about 18v....thing is...I never use it anywhere near max speed even on full power. 12v would suffice, so I ordered this 12v motor controller from Maplins....
http://www.maplin.co.uk/Module.aspx?ModuleNo=30310&criteria=motor speed&doy=18m7
I unplugged the feed to the motor, and removed the original wire-feed control circuit from its mounting, leaving it taped up inside the welder. The original feed to the motor I connected to a 12v automotive relay - just a bog standard thing. With the original wire-speed knobabove 1/3 of the way round, When I pull the trigger, the relay closes.
I then fitted an old battery charger inside the casing too. Its a cheap halfords job, but gives a decent output. The negative from the charger goes straight to the -ve input on the maplins module. The positive feed goes through the relay to the module. The modules output wires go straight to the motor.
I pull the trigger, the old mire-feed controller sends 12vish to the relay, which closes, sending 12v to the maplins unit, which I mounted in the original hole on the welder.
Lastly, I piggy-backed the 240v lead for the charger to the mains switch on the welder so they switch on and off together.
And there you have it.
The maplins unit gives incredibly fine control of the wire speed, from a barely moving crawl to full speed, which is still higher than ever needed with this machine.
The seperate 12v supply means hat the motor speed is NOT affected by the welding arc, so it remains stable no matter what you do with the torch. Gone is the traditional SIP random splattering and it now sizzles perfectly.
The only downside is that I have lost the automatic step-up or step-down of the wire-speed when changing the welders power, I need to change this manually - Hardly a major hardship as I always had to fine-tune it between power settings before anyway.
Since I have had this welder, it has been a chore to use. It was possible to get good welds, but was always hit-or-miss with its consistancy, and it required very regular cleaning and tweaking to keep it useable. I found it would let me down just when I needed it to be reliable. Usually when lying on my back holding a sill panel in place with my head and feet, and trying to tack it in place and getting nothing but crappy bird-**** splatters.
Now though, its a breeze. Its reliable and consistant. In my old workplace we had a couple of top-of-the-range Sealey things, which were great, very easy to get good welds from, now I can honestly say my SIP is on a comparable level with them.
Now, im sure some boffin will come along and point out the phase rectifier electro-shimmy inducer is the wrong polarity to be compatible with the intra-electron transfading multi widget, but you know what???? IT WORKS ANYWAY!