New (to me) Shopmaster 300 with S-22A

[H2o]

Hi all,

So I picked up a Beautiful Shopmaster 300 (serial KB094094) with a S-22A Millermatic wire feeder (serial KB142011). It has sat in my garage for past couple of years but finally got power set up (125amp breaker), and am ready to fire it up.

Prior to turning it on, I wanted to do a quick check of internals, make sure all looks good. I have read that the main switch can have problems as well as some capacitors. Any advice on what to check for? Is there any service manual for these that would help taking it apart, or replacing, checking parts?

I also want to set it up for stick welding. I have two, 25' lengths of 2/0 wire. It seems from what i read that this machine can stick weld more than 300amps?

thanks.

[ryanjones2150]

New (to me) Shopmaster 300 with S-22A

Fire that sucker up man!

[grafk2]

New (to me) Shopmaster 300 with S-22A

I had one in Tech school I taught at, did good cleaning with with air hose to blow out any debris and dust.

[raferguson]

Hi all,

So I picked up a Beautiful Shopmaster 300 (serial KB094094) with a S-22A Millermatic wire feeder (serial KB142011). It has sat in my garage for past couple of years but finally got power set up (125amp breaker), and am ready to fire it up.

Prior to turning it on, I wanted to do a quick check of internals, make sure all looks good. I have read that the main switch can have problems as well as some capacitors. Any advice on what to check for? Is there any service manual for these that would help taking it apart, or replacing, checking parts?

I also want to set it up for stick welding. I have two, 25' lengths of 2/0 wire. It seems from what i read that this machine can stick weld more than 300amps?

thanks.

Download the owner's manual. I don't remember the maximum power output, but I recall that it was a powerful unit. Not a bad idea to pull off the covers, look for anything burnt or obviously awry, and blow out the dust. Unless I saw a problem, I would put the covers back on and power it up. Always good to double check the wiring, both on the house side and the welder side, make sure that it is set for the right voltage, and no obvious wiring problems.

[H2o]

Thank. I will. I could not find anything about how to remove cover. I suppose you need to remove handle, and the bolts all around the sides?

I did a through inspection of my cables. Everything looks good, except for the grounding wire that has seen better days. The jacket is completely cracked probably due to old age. I taped up the bad areas. Inside wire looks in great shape (noticeable corrosion or other damage). But in some areas, when you bend the cable, you can see the copper. I think it might be time to replace that one?

This machine is for home use BTW.

[grafk2]

New (to me) Shopmaster 300 with S-22A

I love those machines, you'll be very pleased. After a good inspection and maybe replace the leads, I'd fire it up also. Good luck and enjoy.

[H2o]

Finally got cover off. Here is what it looked like at first.

[H2o]

After blowing it out. Things look pretty good in general.

[ryanjones2150]

New (to me) Shopmaster 300 with S-22A

Yup, looks like you should fire it up man!

[H2o]

10-4. I will try to do so this week.

Are you supposed to clean/lubricate the changeover switch blades? They seemed like they used to have some kind of gunk on them and years of shop dust. The switch is pretty hard to change.

[H2o]

So finally fired it up this weekend. It worked great. I had not done mig in a long, long time so it took some getting used to. But after a few boogers, I was doing some nice welds.

A few of the gas connections were leaking a little so fixed those. Will need to pick up a new bottle soon as well. Once i receive some parts, I will set up the stick side and test that out.

[ryanjones2150]

New (to me) Shopmaster 300 with S-22A

Glad it's working for you.