Century "five Star" 295ac/250dc Welder

[amuller]

I just picked up one of these for $25 and have been going through it. I checked all the diodes, got the shunt and its operating linkage working smoothly, it seemed ready to go. But the fan motor failed the first time I tried to weld with it. (It was working when I buttoned up the machine.) The motor coil seems to be open and these little motors aren't cheap.

So, are these welders any good? Worth the investment in a new fan motor? Or should I write it off?

I also notice that while the welder is rated 295 A, the instructions inside the cover don't seem to recommend rod above 5/32. Is this really a 295A welder?

Thanks for any guidance.

 

[RJSakowski]

Small fans abound. Assuming the welder is otherwise working, I would just find another fan and swap it out. You should be able to test the function of the welder without needing the fan by making a few short welds.

Based on my Miller welders, there is not a problem with space inside the case. I would think that some of the old 120 vac axial fans which were used on the earlier computer power supplies could serve well. They come with different cfm ratings so look for a higher rated one. Otherwise, fans from old dehumidifiers put out a good air flow.

 

[brino]

Does it have configurable input voltage?
Could you have accidentally put 240V on a 120V fan?
(I only speculate as you don't say how deep your clean-up/checking has been, if you replaced the line cord/plug, etc.)

I have found some welding machines overly generous with their faceplate/marketing current specs.
I do not know this machine specifically, but the best thing to do is try it with larger rods/jobs and find the limit yourself.

However, be cautious of the "duty cycle" rating........you may find you can only weld at higher currents for one or two minutes out of ten!

-brino

 

[amuller]

Does it have configurable input voltage?

Yes, but 208/240.

Could you have accidentally put 240V on a 120V fan?

I wondered about that, too. But there is no neutral in the box, like most welders, and the schematic clearly show the fan motor connected to 240.

(I only speculate as you don't say how deep your clean-up/checking has been, if you replaced the line cord/plug, etc.)

I checked it all out and replaced the plug.

I have found some welding machines overly generous with their faceplate/marketing current specs.
I do not know this machine specifically, but the best thing to do is try it with larger rods/jobs and find the limit yourself.

I take it to be a consumer/farm machine, not an "industrial" box, so some exaggeration for marketing purposes might not be surprising.

However, be cautious of the "duty cycle" rating........you may find you can only weld at higher currents for one or two minutes out of ten!

Especially without a fan!

Thanks,

Alan

-brino

 

[amuller]

Small fans abound. Assuming the welder is otherwise working, I would just find another fan and swap it out. You should be able to test the function of the welder without needing the fan by making a few short welds.

Yes.

Based on my Miller welders, there is not a problem with space inside the case. I would think that some of the old 120 vac axial fans which were used on the earlier computer power supplies could serve well. They come with different cfm ratings so look for a higher rated one. Otherwise, fans from old dehumidifiers put out a good air flow.

The design of this one doesn't lend itself to easy access or a different size fan. I'll have to remove the diodes/heat sinks to get the fan out.

The dehumidifier fan idea is good and I happen to have a couple of dead ones in the rathole. Except that they will be 12o volt fans. Could be connected between a hot leg and the ground but that would not be good practice.

Thanks for the good suggstions.

Alan

 

[LucknowKen]

When the fan on my Powermate 220 Amp mig died the cheapest replacement was over $100 US plus shipping.
The fan motor was 240V. I bought a crate of 220V space heaters that all had good fan motors.
I was shocked to find that the fan motors ($20 for the crate) were a direct fit.
The crate was marked "vestibule heaters".

 

[RJSakowski]

How about an external fan if you can't get one in the box? A 120 volt fan should be OK. Many pieces of equipment pull off one leg for 120. Bottom line, that's whats done anyway, just at your load center. You have an issue if you lose your ground connection but if you do, there are bigger concerns.

 

[amuller]

When the fan on my Powermate 220 Amp mig died the cheapest replacement was over $100 US plus shipping.
The fan motor was 240V. I bought a crate of 220V space heaters that all had good fan motors.
I was shocked to find that the fan motors ($20 for the crate) were a direct fit.
The crate was marked "vestibule heaters".

These welder fan motors seem to be readily available but cost $80 bucks or so. It's a very simple shaded pole motor and it could be the easiest thing to just rewind it, if in fact the coil it really burnt.

 

[chips&more]

Check the fan coil for damage. Does it have that fried smell? Could be just a loose wire/open connection. Does the coil have good color? Then check where the magnet wire/winding wire transitions to a terminal or it might transition to another kind of wire. You can always rewind the coil. I noticed the type of welder you have on the net. The fan motor has a simple one field coil. Easy enough to rewind…Good Luck, Dave.

 

[amuller]

Check the fan coil for damage. Does it have that fried smell? Could be just a loose wire/open connection. Does the coil have good color? Then check where the magnet wire/winding wire transitions to a terminal or it might transition to another kind of wire. You can always rewind the coil. I noticed the type of welder you have on the net. The fan motor has a simple one field coil. Easy enough to rewind…Good Luck, Dave.

Just my own line of thought! The fan is attached to the rectifier assembly and I won't be able to inspect the coil until I take it out, but as far as can tell the coil does not seem burnt, and I don't know why it would be--the bearings are free and it was running fine, and it's *cold* here in Minnesota. So hoping it is a lead connection problem. In any case, the secondaries of the transformer and the choke are aluminum, and the terminations rather rudimentary, so taking them loose for a cleanup and treatment with joint compound is likely enough a good idea.

Thanks again.

Alan