Help w/ Replacing Wire Feed Spd Potentiometer

[Gtp237]

Hi, I have a lincoln "weldpak" 3200hd it's basically just a 135amp 120v Mig. The knob broke off the wire feed speed potentiometer and it appears that the knob is part of the potentiometer.. It doesn't make any sense to me because the knob is on the other side of the front panel. I know I'll atleast need the knob but how do I pull the remaining half of the knob out of the pot? I'm so confused.. Plus where can I get replacement parts? TIA

Pics:

 

[wotwot]

Good morning what are you doing welding at this time of day LOL,
Like most potentiometers there inherant flaw is heavy handed operators knocking them off .
It is replaced as a complete unit not just the knob.
there are a few electronics suppliers online whom you could contact to source one. Just google electronc suppliers.
They only cost a few £s to buy.
And dont worry if a new one looks different as long as its the same rating.

 

[shenion]

Just about any 5k linear taper pot will do.

I'd suggest Jameco Electronics.

Search for "5K POT" Several under $2

Look for one with a 1/4" shaft and a good length, 1/2 watt or higher. Most will be metal so you won't worry about breaking the shaft.

They also have knobs. The old one was probably glued on.

Welcome to the forums.

 

[Gtp237]

Thank you! Google worked well!

But how do you separate the knob to put it in?


And off topic but why is everything inside my welder sticky?

 

[wotwot]

No you unsolder it and put a complete new unit on.
Get some contact cleaner (electrical cleaner)

 

[Gtp237]

No you unsolder it and put a complete new unit on.
Get some contact cleaner (electrical cleaner)

I know but the hole in the front cover is too small for the knob to fit through. I have to put the pot on from the back and put the knob on from the front.

If I just get a universal metal one that is 5k ohm will it have the correct rotation? Will it work like my old one did as far as the numbers on the front panel?

 

[wotwot]

Yes most potentionmeters are the same so with your old knob or new one will work just fine .
As for the Knob thing do you mean it is still attached to the welder.

 

[pedrobedro]

The new pot will most likely have a round shaft with a flat on to locate the knob and it will push on and pull off quite easily.

 

[Robotstar5]

Or pick up a new knob at the same time? and you usually find the shafts come overlength, just cut to suit.

 

[shenion]

The ne part does not have a knob. Like I said the old one was probably glued on after it was assembled (or it is just real tight.)

Pick up a new pot and new knob. I prefer the knobs that use a set screw.

Edit:

Jameco part #s:
potentiometer 255514 $1.65
Knobs: 265009 or 265077 or 162481 all $0.95
(many other knob styles available)

 

[Gtp237]

Thanks so much guys. I found one locally and installed it yesterday. It works great!

 

[wotwot]

And what was the total cost of the repair ?? peanuts i'll bet.

 

[Gtp237]

Yeah it was only a couple bucks. The shaft is metal too so it won't be breaking again. + I was still able to use the factory knob.

 

[wotwot]

Cool glad your repair worked out.If you drop something on the new metal one it will bend and just lock up.
No problem though as you now see how easy they are to repair.

 

[NotANormalCoder]

Just a thought - Many knobs now have hidden fixings. If the knob has a coloured cap, try prising it off with a blade. You will probably find a screw or nut in there which clamps a collet to the shaft of the pot. Of course, some knobs just push on to a (usually) splined shaft.
Dave