Inside the Powercraft...

simon718 · Oct 17, 2008

...if anybody was wondering :whistle:

not exactly the most sophisticated machine in the world, and a lack of smoothing caps... and that fan is absolutley pathetic, next week's task is to source something a little bit more substantial, hopefully make it run a bit longer before cutting out :whistle:

R Kraft · Oct 17, 2008

Cheapwelder improvements

Your Powercraft looks a lot like the Harbor Freight welders.
I've put muffin fans in my welders,they run a lot cooler.
Does the little thing have diodes, to make it DC ?

zzr1200 · Oct 17, 2008

Robert Kraft said:
I've put muffin fans in my welders,they run a lot cooler.

What the fooks a "Muffin Fan"...... :dontknow:

.........

shenion · Oct 17, 2008

zzr1200 said:
What the fooks a "Muffin Fan"...............

Also called a box fan:

rtbcomp · Oct 17, 2008

That fan is awful, and the transformer laminations look skewed. If it's AC it won't have smoothing caps!

simon718 · Oct 17, 2008

Ah i stand corrected, its ac, what do ya expect for 30 quid haha. Shenion that looks alot like a computer fan? Although they are obviously low voltage...

rtbcomp · Oct 17, 2008

Box fans come in 5v 12v DC 110v and 220v AC and no doubt others to order.

R Kraft · Oct 17, 2008

The fan on his welder is a thing of beauty, compared to the original on mine.
But I wouldn't have been able to put the other stuff in without changing it.
Amazing how much stuff you can shove into a $140. welder case.

simon718 · Oct 17, 2008

robert... thats a shockingly sh*t origional fan in your welder :hug:

what all mods have you done to it??

Damaged · Oct 17, 2008

Ehm,

Wouldn't money be better spent buying a decent welder in the first place? :scared:

simon718 · Oct 17, 2008

not if you can scavenge the stuff/ get it cheap enough :clapping:

and the proper welder i want/intend on getting (lorch inverter) is over £500 so a few quid spent on mods to the cheap welder gives an improvement in the short term till i can afford better :cool:

R Kraft · Oct 17, 2008

It has an 80,000mfd capacitor from a communication system.
400 amps in high efficiency diodes from a piece of 3 phase medical equipment.
A heat sink on the diodes from a vfd driver from the heating system at a local school.
A 117cfm axial fan off of a scrapped tanning bed.
I split and regulated the wire feed motor drive voltage and made a stepped (3 speed) voltage, from 0-40,0-200,0-400 ipm of wire.
Added a 200uf capacitor across the wire drive motor to reduce the back emf pulses on the motor and smooth the voltage.
Replaced the nylon wire feed tube with a steel one from an old miller welder.
And I left the switch connectors so that I could use a spool gun.
The open circuit voltage went from 38 to 55 but all of the components are running with a good safety margin.
I spent about $25 on the modifications,wire and shrink tubing and such.
Spent about 8-12 hours of time,if you don't count the time scrounging parts.

shenion · Oct 18, 2008

Did similar to my CP-250, I added 60,000uF in 2 caps. Used flattened copper pipe as bus bar between caps and used 2 ga wire to bridge. Your wires look small

. The CP-250 is 2' wide, 3' tall and 3'deep and it was tight fitting in the caps

It did change the OCV considerably, but it still welds at about the same voltage. I did find on 0.6mm wire the voltage has to be turned considerably lower.

I have 23,000uf X 5 for my DIY welder but could only fit 2 in right now

R Kraft · Oct 18, 2008

I used smallish wire to the capacitor,based on the percentage of the actual power that was ripple.
The welder is only rated at 115amps at 15% duty cycle, with the original parts.
The fan should do wonders for the duty cycle,I can feel a good breeze coming out of the vents.
It should have 10-20% more power with the capacitor.
It is strange that they build something that is supposed to be a linear supply,without a capacitor.

JML · Oct 18, 2008

Did you leave room for the flux capacitors and di-lithium crystals :laughing:

shenion · Oct 18, 2008

Yes, the reason they dont have caps is they are expensive and will wear out. Mine are about $50 each for high-current and high-current grade.

To get any real smoothing (what a linear supply would have.) will take at least 4x what you have. I figure mine make a difference up to about 60 amps. The main reason for adding them was increased arc stability as it was a 3-phase welder run on single phase. The arc has very little buzz.

at only 115A, it should be enough. Mine is rated at 330A max, so I wanted more.

ARCEYETHENOO · Sep 24, 2009

THE POWERCRAFT WELDER IS MADE BY OMEGA WOLF

http://www.omegawolf.co.uk/powercraft/PC Arc (40-160) Manual.pdf

Inside the Powercraft...

simon718

needs to stay off ebay

R Kraft

Member

zzr1200

Working at 650 ft on open steel work.

shenion

Tool Pack Rat

rtbcomp

Moderator

simon718

needs to stay off ebay

rtbcomp

Moderator

R Kraft

Member

simon718

needs to stay off ebay

Damaged

I blame the penguins.

simon718

needs to stay off ebay

R Kraft

Member

shenion

Tool Pack Rat

R Kraft

Member

JML

Member

shenion

Tool Pack Rat

ARCEYETHENOO

Member