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rtbcomp
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The most difficult part to convert Live Torch to Non-Live Torch would be running a wire up the torch and providing a switch on the torch. If they've omitted a contactor on cost grounds they will use a gas valve in the torch rather than a solenoid valve.
On a basic machine a two-pole contactor in the mains leads lead to the transformer should do the trick.
You will also have to provide a low voltage power supply to energise the contactor coil, don't use a mains voltage coil as you don't want mains in the torch.
Next they'll be using clockwork motors in the wire feed
On a basic machine a two-pole contactor in the mains leads lead to the transformer should do the trick.
You will also have to provide a low voltage power supply to energise the contactor coil, don't use a mains voltage coil as you don't want mains in the torch.
Next they'll be using clockwork motors in the wire feed
Won't there already be a switch there to switch the wire feed on and off?
rtbcomp
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andy_burnton
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Another Live Torch machine.
Hi guys,
I recently got a Sealey Mightymig 100 MKII off eBay to do a wee bit of welding on daughter's exhaust and it is a live torch as well. That little piece of information wasn't in the advert (surprise, surprise).
I did think about putting a relay in it. I think the wire feed motor is a small DC one, so could probably take that through a diode to operate the relay.
If I get around to it I'll post some photos and details.
Cheers,
Andy
Hi guys,
I recently got a Sealey Mightymig 100 MKII off eBay to do a wee bit of welding on daughter's exhaust and it is a live torch as well. That little piece of information wasn't in the advert (surprise, surprise).
I did think about putting a relay in it. I think the wire feed motor is a small DC one, so could probably take that through a diode to operate the relay.
If I get around to it I'll post some photos and details.
Cheers,
Andy
rtbcomp
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Don't feed the relay coil from the motor connections, the voltage varies according to motor speed and the relay may not call at lower speeds, you'll need to power the relay from the trigger or the supply to the motor control PCB. You really need the circuit diagram.
You could use a relay to call the contactor, but there will be a time delay from pulling the trigger to the torch coming live, although I guess this would be insignificant.
You could use a relay to call the contactor, but there will be a time delay from pulling the trigger to the torch coming live, although I guess this would be insignificant.
Last edited:
andy_burnton
Newbie
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LIve torch
Hi guys,
Thanks for that RTBComp.
What I was actually thinking of was using a feed from the motor via a diode to the base of a switching transistor ( that only needs 0.6v to switch it on ). The relay would be in the collector feed of the tranny. Can you see any flaws in that ?
Cheers,
Andy
Hi guys,
Thanks for that RTBComp.
What I was actually thinking of was using a feed from the motor via a diode to the base of a switching transistor ( that only needs 0.6v to switch it on ). The relay would be in the collector feed of the tranny. Can you see any flaws in that ?
Cheers,
Andy
rtbcomp
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That's probably the simplest way, but I don't do simple if I can help it 
You're best using a switching transistor, these switch hard on for a range of input voltages, a normal tranny conducts according to the base voltage, as in the motor speed circuit I referred to.
Put a reverse-biased diode accross the relay coil to snub any spikes when it drops, or use one of the new-fangled MOSFET devices.
You're best using a switching transistor, these switch hard on for a range of input voltages, a normal tranny conducts according to the base voltage, as in the motor speed circuit I referred to.
Put a reverse-biased diode accross the relay coil to snub any spikes when it drops, or use one of the new-fangled MOSFET devices.
Not all of the models? I thought they would all be non-live torches nowadays... avoid em, live torches are a real ball-ache to use, especially for beginers.
(you are also better with a gas machine if you intend doing thin car bodywork).
weldequip
(you are also better with a gas machine if you intend doing thin car bodywork).
weldequip
Workman, tools etc
Have i really just joined a forum? oh well. first and last post ever just to say.....read this in disbelief..... "a poor workman blames his tools".... .? oh yes. been welding for God knows how long, army taught and i've me been around the block since but believe me, if you need to weld, and you CAN weld. you make do! if you'd seen the ****e i started with, stop griping like a spoilt child and get on with it. all t'best. E.
Have i really just joined a forum? oh well. first and last post ever just to say.....read this in disbelief..... "a poor workman blames his tools".... .? oh yes. been welding for God knows how long, army taught and i've me been around the block since but believe me, if you need to weld, and you CAN weld. you make do! if you'd seen the ****e i started with, stop griping like a spoilt child and get on with it. all t'best. E.
rtbcomp
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I think that's a bit unfair, lots people on here are just starting out and learning on bad equipment is not the way to do it. I don't care how good you are you will not get good results with crap equipment, how many professional welders will choose Wolf over Milller and all the other top names?
disgruntiled ebay seller maybe
take a chill pill man
seems to be wide spread on forums at the minuteagain!!
Think im hooked....... WFA? anyroad. i weld mostly narrow boats in me spare time and permanent way in work (railway track) use SIP for marine work and MUREX (alumino-thermit) kit for work.... so ya never know i may be able to offer advice or ya could always tell me to **** off granddad! take it easy. E.
Think im hooked....... WFA? anyroad. i weld mostly narrow boats in me spare time and permanent way in work (railway track) use SIP for marine work and MUREX (alumino-thermit) kit for work.... so ya never know i may be able to offer advice or ya could always tell me to **** off granddad! take it easy. E.
nigelmercier
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I've just bought the Wolf 140A from UKHS via eBay. I can confirm that the tip is NOT live until the trigger is pulled.
I do have one problem though, the manual is ambiguous regarding the delivery cables (on Page 5 if you have the same manual). Both of the diagrams show red wire to red post and black wire to black post, and the pictures don't help as they are not in colour, see below:
I do have one problem though, the manual is ambiguous regarding the delivery cables (on Page 5 if you have the same manual). Both of the diagrams show red wire to red post and black wire to black post, and the pictures don't help as they are not in colour, see below:
nigelmercier
Member
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Hi Robert,
Sorry, but I don't understand. I appreciate that the clamp and tip swap polarity for the two modes, but I can't tell which lead goes to which.
