Arc welder fan modification

[urban]

My welder was only a cheap one and as such the duty cycle (think that's what you call the heat cut out) is pretty sweet not helped along by me being pretty bad at arc welding.

Having gained some tips and pointers from this forum i intend to start using the welder again later this week for some more practise.

I had some old computer fans knocking about so thought I'd stick them (literally) in the welder to see if it helped the cooling any and save me spending as much time waiting for it to cool down.

This modification is ropy to say the least and it was only half way through that I thought about taking the pics and posting it up on here.

I'm a sparky by trade so I know how to avoid getting electrocuted (most of the time) but to avoid getting the blame for any fried hair DON'T OPEN UP YOUR WELDER IF YOU HAVE NO COMMON SENSE OR DON'T KNOW WHAT YOU'RE DOING

Always isolate the supply and perform the safe isolation procedure but even then there are components in electrical equipment that can kill you when not plugged in.

anyway, on with the procedure, I took the cover off and wanted to stick the 2 fans on top of each other covering the entire back vent but there wasn't enough room with the iron bar when it was cranked up to full amps so had to put them next to each other at the bottom of the vent.

the 'cowling' is an ice cream tub cut to size

The fans are 12v so the mains power needs to be stepped down to safely power the fans. I used the transformer out of one of those battery charger plugs giving me 12v DC 500mA

using some very strong double sided foam pads the 12v tranny stuck in position

for strength and integrity i always solder wire connections in things like this using thick heatshrink sleeving

The power for the 12v tranny is taken from the switch so the fans run whilst the thermal cut out has cut power to the welding tranny.

Fans in situ

complete ready for the cover

I bent out the vents to try and give more flow

Back together and ready to rock

Testing the flow with a lighter (don't try at home, i had no smoke matches) i was surprised at how much air they pulled through the box.

I'll let you know if it helps any or if it was a complete waste of time.

I had all the stuff and the process took 30-45mins from start to finish. The only electrical protection to the modified circuit is the 13amp fuse in the plug top, bear this in mind if you feel compelled to try this modification, I ain't being held responsible if it burns down your garage or workshop

 

[the snooper]

the only thing i would have done would be to angle the fans inwards so more air hits the transformer, they way you have it it will be blown around the sides

 

[penfold]

I think you'll need something more robust than a sticky foam pad for the transformer; drill some holes in the casing and wrap a couple of zip ties around.

 

[Paul G]

I did a similar thing to a SIP 140 some years ago.

I elected to cut a 5" round hole in the back, cutting through the louvers, and fitting a 240v fan on the outside of the case,
then used a cooker grill pan mesh over the fan inlet.

Before the mod the welder would put down about a dozen hot 2.5's before the cutout tripped, taking about 10 mins to cool.

After it would run 20 odd and 5 mins to cool.

IMHO a very worthwhile mod.

Cheers,
Paul G

 

[urban]

the only thing i would have done would be to angle the fans inwards so more air hits the transformer, they way you have it it will be blown around the sides

I wanted to put them on top of each other but the movable iron bar didn't allow enough clearance so side by side they cover half the vent so wanted to get the maximum fan effect. I've set them up so they're blowing air out of the back vent and sucking it in through the sides and you can feel the pull at the vents infront of the tranny. Ideally I'd like to make some cowls that fit from the fans to the tranny so the only path for the air through the tranny.

I didn't have enough empty ice cream tubs though

I think you'll need something more robust than a sticky foam pad for the transformer; drill some holes in the casing and wrap a couple of zip ties around.

The pads have some serious stick but you're probably right, I'll see how it goes on and if it comes loose I'll go for the cable tie option.

I did a similar thing to a SIP 140 some years ago.

I elected to cut a 5" round hole in the back, cutting through the louvers, and fitting a 240v fan on the outside of the case,
then used a cooker grill pan mesh over the fan inlet.

Before the mod the welder would put down about a dozen hot 2.5's before the cutout tripped, taking about 10 mins to cool.

After it would run 20 odd and 5 mins to cool.

IMHO a very worthwhile mod.

Cheers,
Paul G

Good to hear your mod was worth the time, hopefully this one will be as effective, I'd wanted to use a bathroom extractor fan but didn't have any lying around so opted for the computer fans. If these don't work out I'll get a bathroom one now I know that definitely works.

 

[the snooper]

I've set them up so they're blowing air out of the back vent and sucking it in through the sides

you should have them blowing directly onto the transformer for maximum cooling having them the way you have will just pull air around the transformer not cooling the windings directly

 

[Robotstar5]

you should have them blowing directly onto the transformer for maximum cooling having them the way you have will just pull air around the transformer not cooling the windings directly

All the welders at work have fans that draw air out of the case

 

[Drains]

you should have them blowing directly onto the transformer for maximum cooling having them the way you have will just pull air around the transformer not cooling the windings directly

All the welders at work have fans that draw air out of the case

I looked into this a while ago and whilst my gut feeling was as snoop - for the fan to blow directly onto the transformer, all the machines seemed to suck air out of the casing.

My guess would be that in sucking you get a better air movement up through the casing, and a more even flow over the transformer, so avoiding cool spots as you would get with a blow.

 

[the snooper]

I looked into this a while ago and whilst my gut feeling was as snoop - for the fan to blow directly onto the transformer, all the machines seemed to suck air out of the casing.

My guess would be that in sucking you get a better air movement up through the casing, and a more even flow over the transformer, so avoiding cool spots as you would get with a blow.

when you look at it that way, avoiding hot spots makes sence

 

[urban]

Fan works the dream, didn't cut out once, to be fair I wasn't tanning it but better than it used to be definitely.

 

[Wedg1e]

Nice one; don't forget to stencil the word 'Turbo' on the case and double the selling price. Well that's what the makers used to do, anyway

 

[urban]

Nice one; don't forget to stencil the word 'Turbo' on the case and double the selling price. Well that's what the makers used to do, anyway

turbo badge on order.

I did manage to get it to trip off today with some heavier use but the time off was a lot less than it used to be.