small mains powered fan?

[pondy]

adding another cooling fan into my clarke 150en turbo mig. im adding a euro wire feed motor, my pcb has the power to drive it but the heatsink for the power transistor that drives the motor will just run hotter, so i want to add a small fan just behind the pcb.
this is the motor im adding. have used this guy before and he is very helpfull. the motor is not going to bolt into the welder easy. i need to cut away into the centre plate to get the wire feed more central to the wire reel. but after the welder should be great. the motor does not have enough torque on the lower wire speed settings and judders alot making a bad weld.

http://www.ebay.co.uk/itm/MIG-WELDE...378?pt=LH_DefaultDomain_3&hash=item1c2b7f1a4a

i can find alot of small computer fans but they are all 12v, dont know if there is a 12v feed inside a welder?

this is the best i can find, and its still slightly to large

http://www.ebay.co.uk/itm/80mm-3-23...pt=UK_Computing_Case_Fans&hash=item2c68005b16

any ideas?

 

[PTvor]

I think all 230V fans are big things, but look in the Farnell catalogue.

Is it 24V inside the Clarke? You can make a 12V supply using a three 12V terminal regulator and a couple of capacitors.

http://www.maplin.co.uk/1a-positive-fixed-voltage-regulators-46475

Feed it with the 24V. You shouldn't be pinching much power.You'd have to put it in a box and find some way to solder it together, stripboard or such.

The other way of doing it is to get a socket which fits on a mains lead and a 12 V plug in PSU (wall wart) which are easy enough to come by. Connect the socket to the mains inside the welder, plug in the wall wart. Secure the lot with cable ties and screws to the case. 12V DC whenever you switch the welder on, and no messing with components, or risking overloading or upsetting the electronics in the welder.

 

[CompoSimmonite]

What about a toilet extractor fan - they are small when you remove all the plastic casing.

Paul H

 

[FranV8]

That's what I've bought for my diy tig cooler. £13 in Screwfix.

 

[masleeve]

Maplin do 230Vac pancake fans/
I have just added one to my stick welder to increase it's duty cycle.

 

[tigler]

Use Axial fan 240 as a search term on ebay, this is one a number that popped up,

http://www.ebay.co.uk/itm/Fan-Axial...arden_Hearing_Cooling_Air&hash=item3f1dabe1bf

 

[Wallace]

Not sure what fan your welder already has but I would go for replacing the original unit with the highest flow 240v fan I could get in there to improve total flow through the case. Papst do some good fans.

 

[graffian]

I think all 230V fans are big things, but look in the Farnell catalogue.

I got loads of fans out of my Matsuura electrical cabinets, the originals were 110V, but replacements were all 240V. They look like computer fans, but they are aluminium instead of plastic. So you can obviously get computer size fans that work off the mains. but the welded probably has 12 V floating round in it
and they use very little current.

 

[PTvor]

I got the impression from the original post that Pondy wanted a small fan, smaller than 3", specifically to provide air flow over a heat sink. So he was really looking for something about the size of a small processor fan.

Yes, if the heat sink was in the right place, just put in a 30W full size 230V box fan in place of the original and the general air flow should sort it.

Another thing which would help is to fit a bigger heat sink, if possible.

 

[pondy]

i was going to have a larger heat sink fitted for the motor but the guy who what going to do it and sold me the drive system said it has to power to drive the motor but will run a little hotter, so i just wanted to install a small fan behind it to aid cooling. im not sure on the cfm of the fan in the welder but its right at the back away from the pcb blowing onto the 2 transformers? it would be alot easier to ditch this fan and bolt a larger one on to the back case as there is alot more room. i may also cover the vents with some sort of foam to stock dust and metal particals getting inside the welder? if was really dirty and dusty inside

 

[Wallace]

Filtering is possible but does add expense, a lot more maintenance and restricts flow. A slow build up of dust is inevitable and dependant on how much you use the machine and the working environment. If the inlet and outlet vents are easy to access a regular blow through them with an airline will reduce dust build up then open the case up after a couple of months to gauge how bad it really gets. If not too bad leave it a little longer before checking again. Pulling air through the machine works well.

 

[Shox Dr]

Why bother with a 240v when 12v fans are smaller cheaper and easier to source. Just use a 'ittle tranny to power it.

 

[pondy]

Why bother with a 240v when 12v fans are smaller cheaper and easier to source. Just use a 'ittle tranny to power it.

that might be a bitter idea, and a cheaper one. i looked into changing the main fan. the original fan has a large motor and a 5inch metal fan on it and not much space to go bigger, i have also never had an issue with the duty cycle.

have found a sutible fan in the link bellow.

http://www.ebay.co.uk/itm/50MM-FAN-...pt=UK_Computing_Case_Fans&hash=item19d5a08140

now i just need a transformer, im no electrican so not really sure whats what, this any good?

http://www.ebay.co.uk/itm/LED-Drive...Night_Lights_Fairy_Lights&hash=item4156694d76