TIG questions ? : PT 185

[spiral-cut-bevel]

Hello-
I was given a Lincoln PT-185 as a gift over X-mas. I haven't hooked it up yet due to insufficient power in my shop. In the mean time I’ve been reading up about the machine and tig welding in general. While checking out the control panel on my machine I discovered the Output Preset Control (#5) knob will turn 360 deg. completely without reaching a stop! Does any know if this is correct? Also, my machine came with an air cooled torch. I plan on upgrading to a water torch and closed loop cooler system. Can anyone recommend what brand water torch I should purchase. Should I go with the Lincoln water torch or something like a Weldcraft ? Lastly, does anyone have any advice about building a closed loop water cooler? How many GPM should the system pump flow? Should the system operate on a thermostat? How much cooling capacity should the system have? Can glycol be run in the cooling system (my shop isn’t always heated)?
Any words of advice would be much appreciated!
Thanks- Graham
http://farm1.static.flickr.com/151/379734610_401d692e6b_m.jpg

[Doolittle]

yep, its supposed to be that way. Nothing to break you see. My 205 works the same way. (Its a Digital marvel I tell ya).

[MJDamiani]

I have been watching your post. I received the same machine for my birthday last January and I am working on a cooling unit. I am also going to need the data on the type of pump used and exactly what torch and connections that I will need to make mine water cooled. I have used my TIG for the past year and the torch does get hot when welding above 125 amps.

[Brett]

Ive got a PT 185 415v
The little knob does what you described without any dramas

[duc]

The knob is a position transducer which works on something I'm not explaining at 3am. But needless to say its not like a pot where there is a different resistance value depending on postion of pot.

simple answer: It can spin 360's all day long.

Its almost a shame you cant return the unit and upgrade to the precision 225. I had looked at the 185 but its has a current draw of 70amps while the 225 as a draw of 40amps from the building power. Sounds backwards but it deals with the voltage and the electronics inside. My garage couldnt handle the 70. Hell my house only has 110amp service total.

Dam nice christmas gift though. Either you married the perfect girl or good family.

Good luck

[Tailshaft56]

The position transducer does work different in that the speed you move the knob effects the amount of change. Hence a rapid twist will give a course adjustment and turning slowly gives you a fine adjustment.

As for a cooler in a closed loop system you do not want a thermostat (at least for the pump). Commercial coolers use a Procon pump. Do an E-bay search on Procon pump and you will find several. There is one company selling rebuilt ones set up for this specific application. They were around $65 last time I looked.

[spiral-cut-bevel]

I've stumbled upon some info. Lincoln's coolarc unit has the following specifications:
Provides coolant at:
60 psig
1.66 gal/min
and has a
2 gal. reservoir
Thanks for the lead on the Procon pumps. I found several on Ebay....I may use one or go with an enclosed electric pump....we'll see-

[ptig185]

Yep, they put some kind of rotary encoder in then. It just bump in some detents for a feel of how fast your changing current.

I just upgraded to the 225 and it sure has more ommphff! I really was surprised by the extra heat my torch hand was exposed to as I braced it near the metal while welding. I had it cranked all the way up with a 3/32 tungsten. Had to stop real quick to cool my hot fingers on the ice cold welding table. I know the 3/32 are for up to 150amps but had no 1/8" collet at the time it arrived.
Since then I got the 1/8" collets for by 1/8 tungstens. Still have a water torch to go to when I need more AMP-SECONDS.

The front shows "Micro-Start II"... The PT-185 must be "Microstart 1". Not sure whats different yet but so far it starts just as well as my PT-185.

Brian

[MJDamiani]

[QUOTE=ptig185]Yep, they put some kind of rotary encoder in then. It just bump in some detents for a feel of how fast your changing current.

I just upgraded to the 225 and it sure has more ommphff! I really was surprised by the extra heat my torch hand was exposed to as I braced it near the metal while welding. I had it cranked all the way up with a 3/32 tungsten. Had to stop real quick to cool my hot fingers on the ice cold welding table. I know the 3/32 are for up to 150amps but had no 1/8" collet at the time it arrived.
Since then I got the 1/8" collets for by 1/8 tungstens. Still have a water torch to go to when I need more AMP-SECONDS.

The front shows "Micro-Start II"... The PT-185 must be "Microstart 1". Not sure whats different yet but so far it starts just as well as my PT-185.

Brian,
The PT 225 came out about two months after I got my PT-185. I called my dealer to switch out for a new machine. I was told that it is the same machine and just that circuit board had been changed adding more amps to compete with Miller's 200amp TIG. My supplier offered to get me the new welder, but he said the duty cycle was less than mine and I would probably be happier with the one that I had. I haven't looked at the spec. sheets. I am going to add a water cooled torch even though people tell me that I don't need one, It' my hand that gets hot not theirs. But they are great machines.

[ptig185]

Yes,

Given the same power handling components, I guess the duty cycle at
max current would have to be reduced. It's my over heated glove that limited
"my duty cycle".:eek: