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View Full Version : easiest way to convert stick welder to tig



Timn916
06-21-2007, 07:26 PM
i've read all of the post about way's to convert ac to dc and got confused, i have a 70 amp ac stick welder and all that i'm going to use it for is stainless, i need the fastest and easiest way to go from ac to dc. i seen the pic's moody posted but the supplier needs
more details, also need to know if a light dinner switch will control the amps?

Thanks, Tim

mkirsch
06-21-2007, 07:33 PM
Do you want to convert to tig, or convert to DC?

Sberry
06-21-2007, 08:23 PM
To be straight here, its a waste of time and effort. Lots of energy and you are still left with a piece of scrap when you are finished, even if you could get it to work its life expectancy would be short.

gt403cyl
06-22-2007, 01:16 AM
i need the fastest and easiest way to go from ac to dc. i seen the pic's moody posted but the supplier needs more details
Thanks, Tim

I would say not happenen going from an AC only machine to DC,

There are kits out there to convert to TIG, but I would seriously consider a "bigger" machine I don't know your experiance and what not but to my knowledge you can't just make a switch for AC into DC.

Please correct me if I'm wrong.

GT

injun joe
06-22-2007, 01:25 AM
well why not just buy a stainless steel electrode for ac rather than try to make this all complicated

Timn916
06-22-2007, 08:20 AM
i want to convert it to a dc tig welder, i have a miller ecmo tig but to big to carry on some job sites, so a 110 small tig would do the trick

new_welder
06-22-2007, 09:13 AM
You could convert it to DC using four high current diodes with heat sinks.

Do you know how to wire a full wave bridge?

The following diagram shows how it would be done (bridge rectifier with LC filter).

http://hyperphysics.phy-astr.gsu.edu/HBASE/electronic/rectbr.html

You gan get diodes on ebone -- here's what I found searching for about two seconds (you need four diodes and an inductor if you welder does not already have the inductor):

http://cgi.ebay.com/High-Power-Rectifier-Diodes_W0QQitemZ130127025618QQihZ003QQcategoryZ728 7QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

It would be an experiment for sure. If you want a welder, buy one. If you want to experiment and don't mind the possible cost of failure of the experiment, I say go for it.

vicegrip
06-22-2007, 10:26 AM
You gan get diodes on ebone -- ............
It would be an experiment for sure. ................If you want to experiment and don't mind the possible cost of failure of the experiment, I say go for it.


That's a chuckle !:D

billbong
06-22-2007, 10:36 AM
Hi all, one thing must be realised when dealing with electronics and that is the manufacturers always quote the maximum power rating the device will handle.
This means you halve the ratings, for volts and amps, for workability, otherwise you're running the devices at top wank and this will lead to failure.
If you've got a conventional 100 Amp AC welder, you'll need diodes rated at 200 amps, and voltage above whatever the welder output is running at, probably 50 volts, so a rating of 100 volts is needed.
The big problem with converting a stick welder to do tig is the lack of HF, but more so is the lack of having a foot control.
Once you've had to live with scratch tig you'll in the end spit the dummy and lash out for one of those compact tig jobs that you can carry around.
However just converting a stick welder to do DC welding, by adding a diode bridge and an inductor, is like having all your birthdays at once, it's pure heaven.
Ian.

84ZMike
06-22-2007, 10:59 AM
If you've got a conventional 100 Amp AC welder, you'll need diodes rated at 200 amps, and voltage above whatever the welder output is running at, probably 50 volts, so a rating of 100 volts is needed.


Not true....if you have 100 amp AC and want to use 4 diodes to "convert" the ac to dc then you will only need 50 amp diodes as they will share the load.....100 amps on the + side split between two diodes and 100 amps on the - side split between two diodes.......and I don't see why you'd need 100 v capacity to carry 50 volts......diodes that I deal with are mostly 300 / 600 volt anyway so the v isn't an issue.
Mike

Pumpkinhead
06-22-2007, 01:32 PM
my advise is seein' as how you already want a half-assed welder (no offense), save the bux on converting and buy a low quality DC GTAW unit, Har-bore Freet, one upgrade to ArcOne, two upgrades? (it's a scratcher, but a name brand one at least) to Thermal Arc Dragster.

Mike W
06-22-2007, 01:47 PM
My half-assed welder does the job for me. AC/DC, high freq, and foot pedal.

http://img.photobucket.com/albums/v110/tek798/Welding/tigwelder3.jpg

Timn916
06-22-2007, 11:12 PM
it's 70 amp (campbell hausfeld) so i need 4 35 amp diodes? not sure how to wire it.
i guess some people are missing the point. i have a miller econo tig
and do on the job site stainless welding and customer not setup with 60 amp 220
becomes a problem. as far as starting it i'll be adding a stun gun as a starter.
any pic's will be helpfull.

Timn916
06-22-2007, 11:14 PM
my advise is seein' as how you already want a half-assed welder (no offense), save the bux on converting and buy a low quality DC GTAW unit, Har-bore Freet, one upgrade to ArcOne, two upgrades? (it's a scratcher, but a name brand one at least) to Thermal Arc Dragster.

it's still 220 and i bought one and it sucked

weld_13
06-22-2007, 11:59 PM
My half-assed welder does the job for me. AC/DC, high freq, and foot pedal.

http://img.photobucket.com/albums/v110/tek798/Welding/tigwelder3.jpg

looks cool ta me. so can u switch from tig back to stick on that? i wish i knew how ta make somethin like that. why is it everybody wants dc tig:confused: ? just wonderin cause knew on dc stick it was easy ta start but i dont tig. does anybody know how to make a tig welder from a ac/dc stick welder? thought that might be easier if i was gonna make one for a trial run:D .

Sberry
06-23-2007, 12:33 AM
it's still 220 and i bought one and it sucked
This conversion on a CH will suck too.

weld_13
06-23-2007, 01:31 AM
This conversion on a CH will suck too.

confused was that an answer to the question of wether how much easier it would be to use ac/dc stick welder? if it was gonna be done the dc max woudl be 200amps. thanks

Sberry
06-23-2007, 01:54 AM
It means spending effort trying to convert this machine will not be any better than a HF cheapie, probably not even as good.

calweld
06-23-2007, 02:11 AM
To be straight here, its a waste of time and effort. Lots of energy and you are still left with a piece of scrap when you are finished, even if you could get it to work its life expectancy would be short.

Hey Cary, don't discourage him, you probably had to learn this stuff the hard way, I know I did, I assume this guy's young, we gotta let him learn the same way, just so twenty years from now he can tell some other "young buck" the same thing . . .

Just to paraphrase something I saw on another board, some of us gotta pee on the electric fence ourselves before we learn :p :p :p :o :o :D

Pumpkinhead
06-23-2007, 10:10 AM
it's still 220 and i bought one and it sucked

ummm, althought i don't frequent H.F., i need quality tools, hence i spent the bux for a Maxstar 150STH (it shore am portable), i'm pretty darn sure they have 120V TIG scratchers, the other two listed (ArcOne and TA Dragster) are 120V units, (i also own a TA Dragster as well), so, convert away, spend the money that could go towards a proper machine that won't perform as expected, we used to have a member that could probably sell you plans for converting your Radar Range into a portable TIG too.
for me t'ain't gonna happen, that's why we have lil' Chinese workers, to make cheap but effective tools for skinflints.


This conversion on a CH will suck too.

It means spending effort trying to convert this machine will not be any better than a HF cheapie, probably not even as good.

weld_13
06-23-2007, 12:48 PM
Hey Cary, don't discourage him, you probably had to learn this stuff the hard way, I know I did, I assume this guy's young, we gotta let him learn the same way, just so twenty years from now he can tell some other "young buck" the same thing . . .

Just to paraphrase something I saw on another board, some of us gotta pee on the electric fence ourselves before we learn :p :p :p :o :o :D

well thankyou for tha respect:) . yeh i know im peein on the electric fence here:eek: ow it shocked me:D .so how do the hf cheapys do then? i thought about buyin one once ta try tig out but decided not to cause didnt have a foot petal and amp settings were only 1-5 which didnt seem to appealing cause it was a tig/stick inverter and i cant stick without seein my amp settings thats just how i am im picky. i guess im gonna look to ebay for a cheap tig then thanks guys.

Aeroweld
06-23-2007, 03:04 PM
it's 70 amp (campbell hausfeld) so i need 4 35 amp diodes? not sure how to wire it.
i guess some people are missing the point. i have a miller econo tig
and do on the job site stainless welding and customer not setup with 60 amp 220
becomes a problem. as far as starting it i'll be adding a stun gun as a starter.
any pic's will be helpfull.

Why not let your "fingers do the walking" in the Yellow pages and rent a Maxstar 150 for the time you need it. Just add it into the cost of the job.

Aeroweld
06-23-2007, 03:07 PM
It means spending effort trying to convert this machine will not be any better than a HF cheapie, probably not even as good.


Very well said Cary

Sberry
06-23-2007, 11:11 PM
1-5 is just as good as any other set of numbers, the rod doesnt know what is on the name plate.