Make it Good

[ramblerx15]

I received as a gift, one of those Harbor Freight TIG inverters. I unpacked it and removed the cover to look it over. Well, it's not a Lincoln for sure, but I had some ideas on how to improve it and make it suitable for playing around with. The manual was disappointing, as it lacks anything informative about how its cycle works :confused: so I guess you are on your own. I read on another thread about somebody adding a foot pedal on one of these inverters,so I am thinking it may be possible. http://www.weldingweb.com/showthread.php?t=4927&highlight=foot+pedal
I have a pedal, salvaged from a Cebora (Italian) machine, that I think could be grafted onto this, with a few modifications (and some dumb luck):laugh: I will be posting some pics, and soliciting advice from y'all and try to make it good. Thanks in advance......T

http://i15.tinypic.com/2ahbhv7.jpg

[zapster]

i hav'nt the foggiest idea of what you just typed..

but good luck with your adventure!

..zap!

[drivesector]

i hav'nt the foggiest idea of what you just typed..

but good luck with your adventure!

..zap!

Yea what he said.

[elvergon]

Electric shock can kill....man if that´s what hair dryers say......I think you get the point....

Just make sure you have someone that knows about electricity...

[ramblerx15]

with a few modifications (and some dumb luck):laugh: I will be posting some pics, and soliciting advice from y'all and try to make it good. Thanks in advance......T

OK here is a pic of the inside. The Chinese don't seem to be too shy about sticking things on with a hot glue gun. Unfortunately the glue didnt stick very well,so things like the power switch, LED's, potentiometer,etc. are kinda floppin' around.
http://i9.tinypic.com/48m0g79.jpg
Well I have a hot glue gun so that shouldn't be a problem. :laugh:

[ramblerx15]

OK here is a pic of the inside. The Chinese don't seem to be too shy about sticking things on with a hot glue gun. Unfortunately the glue didnt stick very well,so things like the power switch, LED's, potentiometer,etc. are kinda floppin' around.
Well I have a hot glue gun so that shouldn't be a problem. :laugh:

So my idea is to put a switch in for pedal or panel,and wire in the linear type pot in the pedal. How do I determine if the pots are compatable? by reading and comparing the resistance values with an ohm meter? I am going to be handicapped by the fact that I do not have any 220v service in my workshop :mad: Then wire the contactor switch in the pedal to the gas solenoid, which I am not sure what kind of timer they have on there. I figure since it is scratch start, just use the foot contactor switch for a pre/post flow control. I wonder what kind of voltages run the gas solenoid? judging by the wire guage, not much.but the cooling fan is labeled 220v.I guess the next thing that I need to do is see about getting some 220v! Electrician in-laws will be here for Thanksgiving dinner, hmmmm........T

[MucWad]

I like how they paralleled so many little scr or triacs to make it able to handle the power as for the foot pedal you can just parallel another pot in there so when pot1 is say at x resistance and pot2 is at 0 or as close as it can some you will get full power then when pot2 increases the welding amperage decreases. If you want more info I can say more but right now it is 12:15 and I am going to bed just thought I would chime in real quick.

[ramblerx15]

I like how they paralleled so many little scr or triacs to make it able to handle the power as for the foot pedal you can just parallel another pot in there so when pot1 is say at x resistance and pot2 is at 0 or as close as it can some you will get full power then when pot2 increases the welding amperage decreases. If you want more info I can say more but right now it is 12:15 and I am going to bed just thought I would chime in real quick.

Great! this is what I am looking for, brainstorming! Please continue when You get the chance. Thanks.....T
heres another internal pic
http://i15.tinypic.com/2ep1xzp.jpg

[runchman]

I had this same unit for a few weeks, and I played around with a second pot as a simulated foot control.

My idea was, use the pot on the panel for the 'max gas' control, and have the foot pedal pot go from 0 to max gas. I actually wired in a 2nd pot, then took it out and returned the whole unit to harbor freight.

It's too late for me to recollect exactly what I did ('specially after a couple drinks) but if you want to PM me I'd be glad to work through it with you.

I have an EE degree so if I can't figure it out I better be fired !

- John

Oh yeah if you don't have any already, get some real tungstens, the ones that come with this are more like pencil leads. When I got some real ones, they barely resembled the HF ones.

[ramblerx15]

I have an EE degree so if I can't figure it out I better be fired

.. get some real tungstens, the ones that come with this are more like pencil leads. When I got some real ones, they barely resembled the HF ones.

You said it! lol :laugh:
I did notice the 'pencil lead' tungsten :p Will the standard weldcraft type collet bodies fit in this China torch? I have a 250 amp aircool layin around but it is much larger and I would have to rig up connections etc., but I have a box full of collets, tungsten, and stuff. I will rig it up if I cant get anything to fit the HF special. Thanks .....T

[runchman]

You want tungstens and collets and what not for a #9 torch, should work fine.

- John

[fun4now.]

i think runchman had the right idea take the hole thing back add a few $$ and get a real TIG unit, even after messing with this POS to get a foot controle working if you can you will just have a POS with a foot control that you spent way too much time for the quality of weld you are likely to recieve.

[runchman]

i think runchman had the right idea take the hole thing back add a few $$ and get a real TIG unit, even after messing with this POS to get a foot controle working if you can you will just have a POS with a foot control that you spent way too much time for the quality of weld you are likely to recieve.

I think it boils down to what your financial situation and spending desire is. If there is no way you want to plunk down the cash for a 'real' unit, I think this one is fine to at least have some fun tigging steel.

On the other hand, if you can swing the money, you'll probably end up doing it eventually anyway !

- John

[fun4now.]

TIG being one of the harder welds to lern i think a crapy unit would just tend to frustrait you and put you off ever lerning it, where with a good unit you will have a beter chance of picking it up.;)

[Rojodiablo]

TIG being one of the harder welds to lern i think a crapy unit would just tend to frustrait you and put you off ever lerning it, where with a good unit you will have a beter chance of picking it up.;)
For DC welding up to 3/16" steel, this unit works ok. Not the best, but it works with the same principles as say the Miller 150 lift-start. All it will take is practice. He is going to work with what he has, not what he dreams of. So give him ideas how to do it as well as he can. With that, make sure you use the good tungsten mentioned, and get some good filler rod. And just practice.:waving:

[ramblerx15]

For DC welding up to 3/16" steel, this unit works ok. Not the best, but it works with the same principles as say the Miller 150 lift-start. All it will take is practice. He is going to work with what he has, not what he dreams of. So give him ideas how to do it as well as he can. With that, make sure you use the good tungsten mentioned, and get some good filler rod. And just practice.:waving:

It all boils down to money on my end, poor folks have poor ways. Since it was a gift and I already had that pedal ,time for a merger. As far as 'learning' , some of my tig welding is orbiting on the International Space Station as we speak. I am fixing this machine as part of my therapy, re-hab from multiple sclerosis. I feel its a good thing because 3 yr ago I was wheelchair bound. I am trying to rat hole the cash for a proper machine, but this is the deal now. "make do with what you got" I appreciate all the input from y'all, good or bad :laugh:

[fun4now.]

if you already know how to TIG weld then you should be ok, even better if its an exersize to keep you buisy. i spent 4 days making a child cart to pull behind my bike, because i had no $$ to buy a new one partly and partly to give me some thing to do. all in all it came out great i think but to try to make them for sale would be insane with the time the wife and i have into it, but its the only one out there like it.:)
i hope it works out for ya.:cool2: i can certinaly understand 1/2 the funs in doing, and doing what you can with what you have.;)

[ramblerx15]

After discussing the subject, on this board and else where, I am now leaning toward abandoning this project and returning this welder to HF. My biggest concern is not having enough output power for the times that it is needed. I can't recall ever using a 1/16 stick electrode, and really have only seen them at HF. Another thing that kinda bothered me is how is it a 130A tig ,but only a 70A arc welder? there is no process switch, so how does the machine know what u have hooked up to it?
Another thing is, I really like welding on aluminum, so AC welding is kinda needed!
So the search goes on, and I guess its O/A or nothing. Thanks to all who offered their .02.

"You can't park that here."
"I'm not parking it, I'm abandoning it."
:waving:

[fun4now.]

my TA is the same way 185 TIG and only 150 stick, but i have to tell it wich ine i am using.;)
sorry to here you abandend the project, but hope you find a TIG unit to play with soon its a lot of fun and verry relaxing.:)

[elvergon]

There´s a guy here that made a nice TIG pedal for the same machine. If you want to have AC you´ll go with some BIG $$:..but at the end it will be well worth...

Might wanna check out the link, seems the pedal works just fine.

[runchman]

After discussing the subject, on this board and else where, I am now leaning toward abandoning this project and returning this welder to HF.


Uh-oh you've caught the tig fever, watch out, your pocketbook will feel the hit soon !!!


- John

[ramblerx15]

Uh-oh you've caught the tig fever, watch out, your pocketbook will feel the hit soon !!!

ok I went and did it,got my refund from HF (tax and all $250 ) and bought a new Dragster 85, plus a wp9 torch, collets, bodies and cups, and .020,040 and 1/16 tungsten. All of this stuff shipped to me was about 5 bucks or so cheaper, good deal? I thought so!
I can't wait until it arrives :cool2: Ebay was my friend in this deal, as all 4 items came from different vendors. I will post some pics later of the fine welds it makes. :laugh:

[MicroZone]

A dragster 85 ? :confused:

[fun4now.]

congrats, i hope all goes well from here.:)

[cmartman46]

Looks like alot of research went into this pedal project. I can tell someone knows there@#$%!
I lack in the electronics department. I am impressed with your knowledge, which comes to my question
I have a Thermal arc 185 AC/DC inverter tig welder. They want close to $300 for a foot pedal.Not gonna do it! I'm not sure if I made a mistake buying a Lotus foot pedal off of Ebay for $69+ shipping . It seems to be of a pretty good qaulity for the price. The pins dont match up but I got in touch with Tyco electronics and found a matching male plug that will fit the welder, #206434-1.
The pedal that I purchased has a 5 OHM pot that has 3 wires conected to it(red-yellow-green). Has a on/off pedal switch with 2 wires Black and Brown.
TA185 AC/DC tig welder diagram:
Pin# 1........chasis ground
Pin# 2.......contactor control/+24VDC
Pin# 3.......contactor control/GND
Pin# 4.......not used
Pin# 5.......potentiometer maximum
Pin# 6.......potentiometer minimum(GRN)
Pin# 7.......amperage control wiper 0-10 VDC
Pin# 8.......not used
Can this pedal be wired in to fit this welder from the info I provided? If need be I can put up more info from the diagram schematic. Any help would be greatly appreciated!

[fun4now]

look for a scs foot control on e-bay. they run about $165 with high quality.

[GT Steve]

Cmartman46,

The resistance value you list for the purchased pedal seems a bit low (5 ohms), typically on the inverter machines it is more like 500-1000 ohms. The danger there is overloading the current control circuity in the TA 185 and that would be mostly bad.

You can verifiy that resistance by putting a multimeter between the V+ and ground reference wires for the pot. The resistance between these two will not change when you press the pedal. The resistance between V+ and the wiper and ground and the wiper will change with pedal motion. With the pedal in the up (off) position, the pair of wires with the lowest resistance is your wiper and the "ground" wire.

If you can verify that the pot in the pedal is the correct resistance, then based on all the other information you provided you should have no problems hooking it up.

Anyone know what the reistance value should be for a TA 185 pedal?