welding cable reels

[alltoys]

30 years of welding has taught me that unequal lengths of cable does make a difference. I have also learned to unroll the full length of cable off the reels no matter how close you are to the project.

There is a difference in arc characteristics between a short ground cable and equal length. One of my first winter jobs using a portable in the oil patch I used unequal length cables and had 2 break downs with my machine. When my welder mechanic asked me what I was doing to have such problems with my welder. I showed him. Soon as I used his equal length cables there was no more problems. There is a higher load on the machine with unequal length cables.

For those of you who are weekend welders you probably wouldn't notice the difference.

 

[Willl]

For those of you who are weekend welders you probably wouldn't notice the difference.

Ya, that must what it is.

 

[Scotty370]

Easy ...Willl....!!! That's what I'm blaming all my bad welds on from now on! Maybe if I took a couple vacation days, and welded during the week........Hmmm........

 

[jenkinsph]

It seems that most of the companies such as Lincoln and Miller provide accessory kits with unequal length cables from my research this morning.

I am looking for facts about this issue of unequal length cables and prefer to be open minded. Having been a broadcast engineer for many years I feel that I hae a basic understanding of electricity. This unequal length theory is in conflict with my understanding of electrical properties. Would like to know how the unequal length cables load down the machine more than equal length cables do.


Might be a good test for Myth Busters.

FWIW, I have equal length cables.



Steve

 

[tommu56]

I've never seen a problem with unequal length's.
I worked in a fab shop after high school and they used the building frame as ground and a shepherds crook off the steel to ground piece with 100 - 150 foot of lead wire to welder and the ran the best welds with that set up
they were ac motor/ dc gen welders from Lincoln.

on the reel thing remember you are making a electromagnet in dc and a transformer in ac that could produce some unwanted results.

again in the fab shop we had old car rims mounted near welder and the unused wire was put on in a figure 8 or looped off one side back same side to the other side with the excess left on rim while the were welding. This helped with the kinking and twist problems too.

tom

 

[BrentD]

You know... I just thought of one possible, albeit indirect, way using unequal cable lengths could cause problems.... If you happen to leave part of the longer cable coiled up you'll make an inductor / choke and at high currents, you can create reverse voltage spikes into the welder as the magnetic field collapses in the coil.

 

[Hooked_on_HP]

Well, with all these posts I would have thought some one would have had some thoughts on making some reels. BTW they are putting a new water tower up on my way to work so I stopped to ask the welders about the different length cables. They thought it was funny.
Bill

 

[JoelD]

One thing I can definately attest to is that you definately do not want to weld with coiled leads. I fried my rectifier in my bluestar. I purchased my machine, amazing ebay deal by the way, 70 hours on the machine, and about 400 foot of 0 cable. Each length is about 50 foot. I was welding with the cable coiled up as I typically weld near the machine. Well after probably 5 or so hours of intermittent welding my machine would rev up, then stumble to it's knees then rev up and stumble, it was a violent act. Anyway after much volt meter testing I diagnosed with the help of the miller tech on the phone that the rectifier had fried. His first question was, do you unwind the leads and I said no, and he said, there you go.

I replaced rectifier (tech had one at his desk and actually mailed to me, amazing customer service, even if he hadn't mailed he spent many hours on the phone with me over a number of days). New rectifier and problem gone, I've used machine for two years since without a hitch (104 hours as of today).

The wound cable made huge resistance, huge magnet actually and fried the rectifier.

This note reminds me, I should make up shorter leads as I never need that much length.

Joel

 

[sandman2234]

If different lengths of cables matters, what happens when you hook the ground to a steel building halfway around the block from where your actually welding (and hundreds of yards nearer to the machine)? I can't see the machine knowing where the copper ground starts and the steel building starts, so I have my doubts about the validity of this myth/truth.
David from jax

 

[BrentD]

On the original topic of cable reels, I really like the mechanism they use to wind wire off the big rotating rack at the local Lowes. The "spool" is made of a bunch of flat stock with joints so it can bend kind of like one of those Hoberman Sphere toys. The "spool" part expands and the flat fingers form the outer rim of the spool and hold the wire on. When you're ready to take them off, the flat finger all bend toward the center of the spool and the spool's diameter colapses so the entire coil of wire slides right off the side. Don't know how practical that would be for your setup, but it would definitely make for a fast unroll.