MOD? Just an Idea for space. Check it out!!

[nobel12]

Hello everyone,

Here's my first post.(try to to kill me ok) I had a thought on how to get more space inside your small welders in order to make the mods you might want.

Why don't you use a computer fan mounted on the exterior of the welder, (plus a grill over it to protect the little fingers out there) ?? I know most fans can be purchased in almost any voltage (not just 12vdc for comps). This would free up a good amount of space for adding additional mods to your welders.(if your thinking about it anyway) Plus it would be wise to remove the louvers and change it to a full size hole for air flow.

My next thought was this if a person could add aluminum heat sinks to the main transformer it could maybe reduce heat and extend duty cycle time to the unit at max output ranges. My only real concern with this is inductance from the trans??? Is this possible, maybe, I'm not sure to be honest. But I will be finding out.

My last thought for today, If a fan is controlled by a thermal switch in your unit, ( doesnt turn on until it reaches a set temp ) why wouldn't you remove the thermal switch? Wire it directly to the main switch so the fan is always on when the welder's main switch is on. This would make it take a little longer to heat up and give faster cooling when not actively welding. Or so it would seem to me.

I'm an electrician for 17 yrs mostly commercial and industrial, back round in electronics from high school and airforce, built a few custom water cooled computers, love machining on my drill press, and love working on strange projects, and now I'm back to welding. ( haven't stick welded since high school 22 yrs ago) OHH BOYY

My used welder from ebay should arrive in a week, nice new mod project, and as usual I'll take a weak something and try to turn it into a beast

I've read a post about safety and mods done outside of the welders, This Really Isnt Smart!! I am hoping that my ideas will give some room to put these mods back under the cover where they should stay! Be safe, have fun, don't get dead!!

Please, I would love to here feed back about my suggestions!! Besides if you read all this, you must have some thoughts !!

 

[R Kraft]

Most of the small welders have a fan that comes on when the power switch is turned on.
Usually a small, inefficient fan.
Usually they have plenty of louvers, just not enough fan to move the air.

I like redesigning the little welders, I've made mine unrecognizable by the manufacturer.
What kind of welder are you getting ?
Robert

 

[nobel12]

It's an ATD model 37130, it cost me $100.00 US and it's used, made by cebora, so its nothing special.

I really think a computer fan with the right voltage can move a good bit of air, usually do.

What about my heat sink idea? I bet it helps, do you think?

 

[R Kraft]

I'm not sure how much heat the iron core retains in relation to the internal heating of the windings.
It may be worth a shot.
The main thing I noticed about the original fan, was that they don't even vent the inside of the case properly.
Here's a look at a thread that shows some photos.:http://www.mig-welding.co.uk/forum/showthread.php?t=8046
Robert

 

[nobel12]

robert, that welder looks like the sandwiches i like to make!! ITS STUFFED

do u have a link to some of the mods you've done there in the photo? Also, I'm still looking for good help on caps and sizes to use, seems like there is alot of random info out there, would like to smooth out my arc but not add to much on the amps drawn as a whole.

 

[R Kraft]

Just the general specs.
http://www.mig-welding.co.uk/forum/showpost.php?p=87153&postcount=12
If you take your max amps @ volts from your welder to get the resistance of your windings and the arc channel and use the capacitive reactance formula at 120hz, it will give you a ballpark calculation of your necessary capacitance.
For instance 120A@20v=.166ohms of resistance
For a time constant of .00833 seconds or 120hz, you would figure the energy stored in the capacitors,E= V^2*C/2 . TC= R*C. 1/e = 36.8%
20v at .1666ohms would need 49890mfd or about 40000mfd per 100A.
That seems to be the way the manufacturers figure it.
Any capacitance helps and more would be some better.
Robert

 

[nobel12]

OMG!!! someones trying to take me back 20 yrs ago

Ok, I'll try to get it right, but I would like to run it by you when I do this if thats alright with you?

Also, will the welder draw more amps from the house if I use/add caps? (assuming the welder doesn't have them)

 

[shenion]

If you are doing thin metal, you don't want to add big caps. It will raise the RMS voltage up and thus the current.

They will also add a considerable start current to charge the caps.

You might start with something small like 2200uf/50V (100V is better). That will add some arc stability while not increasing the average voltage much.

 

[R Kraft]

It should make no noticeable difference in the power requirements.

A 135A welder should be fine with 60,000mfd, 100,000mfd would be good .
Just remember that the caps will charge to peak voltage, not RMS.
That will raise your Open circuit voltage times 1.414.
Robert

 

[shenion]

It will also raise the welding voltage. At 100A, it will still be about the same. At the old 30A setting it will likely be around 50.

 

[nobel12]

So if the manual I found online says at position #1 ac volts in at rectifier is 23 and dc volts out is 19.2 what would I be looking at after caps? I mean like maybe a ball park idea anyway??


I'm really looking for the happy middle, smoother arc/minimal output voltage change. Know what I mean?

Don't start fitting already!

 

[the snooper]

dont really see the point in using a pc fan and mounting it externally would it move enough air ?.
also you may aswell just mount the original in the same way with protection around it probably not worth the effort

 

[nobel12]

I guess it should be mentioned that computer fans come in tons of sizes and cfm's. And you can get small grills to cover the exposed fan blades if you like. couple bucks to be honest.

I just figured it might free up some space is all in smaller welders for people who would need it for additional parts they might want to add.

Like I said at the begining, its a thought from my experience at modding computers and the fact that good air flow is critical to heat disappation with the box. Maybe take one idea to a different application.

Hey maybe add two fans one in the front sucking air in, and one at the rear blowing air out. Make a wind tunnel!!

Just thinking out loud.

 

[nobel12]

Try this on for size. A company called koolance, makes a compoung for hard drives that is like a paste, it is placed directly into contact with the circuit board compontants ( wont electrically short anything ), its designed to wick heat away from the board and parts of the hard drive. Pretty cool

So here goes crazy talk( or is it ) try completely wraping the windings in this stuff like the entire trans in the welder, then add aluminum heat sinks all around the trans to disapate heat, then add two fans to the welder for an air tunnel affect that goes right accross the heat sinks.

Anyone understand what I'm suggesting now? maybe not.

 

[the snooper]

yes you are on about the white heat transfer paste used on ic`s like the cpu in your computer the fans back and front of the heat sink one blowing one sucking worth a thought wouldnt try it though if my welder went it would be like losing an arm

 

[nobel12]

Its not like the white paste on ic's but it disappates the heat in the same manner, more like a wood putty that stiffins to a gel, its really cool stuff!!

 

[arcpaws]

Regarding heat sinks, I imagine the biggest problem is getting heat out of the windings themselves, since there are air gaps, insulation, etc between the windings and the core. I guess that's why really hard working transformers (e.g. substations) are filled with oil. It also means they explode spectacularly...