Welding Tips and Tricks

Hello
On youtube some people change the Harbor Freight 90 amp welder to negative gun and to positive ground.
They do that by adding capacitor and Bridge rectifier into the circuit.
Anyone on this forum ,did you try the change over,did you find the welder any better after the change over
mrel.

A guy I work with did this to his machine. Said it cost him less than 20 bucks and made a big difference.

possible but how common is a rectifier of that size ? i'm guessing not all that common to find.

the other thing is its still a pos machine which is probably going to die for other reasons. is it worth spending even more money on ?

There's a video series on the conversion on YouTube. They use surprisingly small rectifiers. Parts to do this are easy to source.

tweake wrote: the other thing is its still a pos machine which is probably going to die for other reasons. is it worth spending even more money on ?

Some times, inexpensive tools last elephant years no matter how poorly made, how roughly treated, and infrequently used. If the OP only needs to turn a screw every once in a while, why purchase a full set of Snap-On screw drivers? (As an analogy).

cj737 wrote:

tweake wrote: the other thing is its still a pos machine which is probably going to die for other reasons. is it worth spending even more money on ?

Some times, inexpensive tools last elephant years no matter how poorly made, how roughly treated, and infrequently used. If the OP only needs to turn a screw every once in a while, why purchase a full set of Snap-On screw drivers? (As an analogy).

to continue the analogy,
the cheap screwdrivers round off after the first dozen screws and you end up stuffing up the screws. its then thrown in the bin and you go buy better screw drivers.

don't get me wrong, i don't mind cheap nasty tools when you know they are just going to get munted anyway.
you don't always have to go buy the top brands. i certainly do not have a top brand welder, but its also not as cheap and nasty as that mig.

if you want to do it as a project and see what you can get out of it, go for it.
but if you just want a welder that works when you need it, get something better.

btw i see ChuckE2009 has done a couple of vids on cheap welders. worth watching.

I got question, I am sure it could be a translation mixup, I have seen few videos and I got the parts, Bridge Rectifier 150A 1,600 Volts, 50V 50,000 uf capacitor, now the part mention to discharge the capacitor after turning off the machine is where I got confused, I Google the part and got an image of something that looks like a flat washer made of Ferrite I think, then read that what I need is a choke, also got me more confused, right now all the parts are in the mail but that one that is supposed to discharge the capacitor...........AZ

AZlink wrote:I got question, I am sure it could be a translation mixup, I have seen few videos and I got the parts, Bridge Rectifier 150A 1,600 Volts, 50V 50,000 uf capacitor, now the part mention to discharge the capacitor after turning off the machine is where I got confused, I Google the part and got an image of something that looks like a flat washer made of Ferrite I think, then read that what I need is a choke, also got me more confused, right now all the parts are in the mail but that one that is supposed to discharge the capacitor...........AZ

you need an inductor. no idea on size possibly one of the vids will say.
your probably looking at a ferrite ring with wire wrapped around it.
the other thing is possibly a drain resistor across the capacitor. a high value resistor that drains the cap when you turn the welder off.

also have a look at
https://en.wikipedia.org/wiki/File:RLC_low-pass.svg

tweake wrote:

AZlink wrote:I got question, I am sure it could be a translation mixup, I have seen few videos and I got the parts, Bridge Rectifier 150A 1,600 Volts, 50V 50,000 uf capacitor, now the part mention to discharge the capacitor after turning off the machine is where I got confused, I Google the part and got an image of something that looks like a flat washer made of Ferrite I think, then read that what I need is a choke, also got me more confused, right now all the parts are in the mail but that one that is supposed to discharge the capacitor...........AZ

you need an inductor. no idea on size possibly one of the vids will say.
your probably looking at a ferrite ring with wire wrapped around it.
the other thing is possibly a drain resistor across the capacitor. a high value resistor that drains the cap when you turn the welder off.

also have a look at
https://en.wikipedia.org/wiki/File:RLC_low-pass.svg

Yes sir, that is what I found but without wire around it, it was just a flat ring, is that the choke I read about?

AZlink wrote: Yes sir, that is what I found but without wire around it, it was just a flat ring, is that the choke I read about?

you need the wire wrapped around it. normally they come pre made. i have no idea what size one you would need.
a choke is an inductor.

tweake wrote:

AZlink wrote: Yes sir, that is what I found but without wire around it, it was just a flat ring, is that the choke I read about?

you need the wire wrapped around it. normally they come pre made. i have no idea what size one you would need.
a choke is an inductor.

Thanks for the help........AZ