Crimping lug on welding lead

[wb4rt]

What seems like just a simple question, until you get the answers - is there any trick to crimping the lug on a welding lead? Do you need no-ox or anything? Just crimp with a vise, hammer, or ? ? ? My LWS said to use a larger lug and double the copper over for a better connection. Any thoughts?
Thanks - you never know what your missing unless you ask or examine the wreckage.

[enlpck]

Generally, you want to use the tools and methods the manufacturer specifies.

Use the proper lug size for the best results. Crimp sufficiently, but don't overcrimp, or either the lug body or the stranding of the cable may be damaged. Doubling over won't improve the connection, and will likely make it worse, as the fold takes more room than the doubled segment of cable, so the lug would need to be much oversize.

My suggestion would be to either get a hydraulic setup (if you do enough crimping yourself, or can borrow or use someone else's), or use a hammer crimp set (cheap, they work fine). We use both at work. The hammer job for smaller stuff and repairs out of the shop, and dies in a press for larger stuff. Dies were made up in little time by modifying an existing set that were worn out for the original purpose.

Crimping by squeezing in a vise isn't reliable... it won't for the lug properly and won't give uniform compression. No-ox has things in its favor, and things against. I don't use it, and a good tight crimp job will break through any light oxides while you crimp, and will be, for all practical purposes, gas tight and not oxidize internally. You may corrode the lead off outside the crimp zone, but that can happen no-ox or not.

On the hammer type, drive as specified in the instructions. Resist temptation to use too heavy a hammer or keep whaling away at it. The crimp will fail if you do. Also, DO NOT be tempted to solder or braze into the lug unless the lug is designed for the application, and do not solder or braze a lug that will be or has been crimped.

[wb4rt]

enlpck,
Thanks - that is exactly what I wanted to know. I know it seems simple, but a lot of things I do seem simple to me, but buffalo everybody else.
There's nothing like experience to turn a so-so job into a first rate job.
If anyone else has any suggestions or knowledge to share, feel free to add to the post.

[rlitman]

A hydraulically crimped cable connection is probably the best and strongest way a cable can be connected to anything. The crimp itself will be air tight, and corrosion should not be a concern inside (especially with copper). no-ox isn't necessary.

Crimps made with crimp dies manually closed in a vice, are just about as good, and hammer crimps made with a die -can- be just as good.

All of these crimping methods really require a gauge, to verify that the crimp was done correctly.
Too large, or small, and its no good.

Crimped directly with a hammer or just a vice isn't a substitute at all, and creates an uneven shape that can cause problems.

Solder has two problems:
First, it can melt if the wire gets too hot, but if the solder is melting, your insulation would be smoking as well, so this isn't a big concern to me.
Second, it wicks into the cable making the end more stiff. That causes the cable to fray where it flexes just past where the solder wicked up to. Solder might not be a problem for you, if your connection includes a rigid strain relief that goes well past where the solder could have wicked up to.

For a different type of connection:
I have a lot of connectors for #0 and #2 welding cable, with a large set-screw with a ball end (dinse, quick connects, ground clamps, stingers, etc).
On those, I like to cut a small rectangle out of a copper pipe, to crush the cable more evenly, and keep the entire cable under pressure (not just what's under the screw).

[mudbugone]

Don't know how many crimps you are making,but I see manual crimpers on Ebay often go for $12-15. They look like little jacks or cable cutters that you hit with a hammer to crimp on connectors. Harbor Freight may carry them also(haven't checked).

If you only have to do a few--- find an electrican or a powerline truck...they are usually easy going on such things....and happy to be of help usually.

[lugweld]

I solder my lugs on. I start by heating the lug in a vise with a propane torch, then adding rosin core solder about 1/3 -1/5 full and is molten. Then, I take the prepped cable with insulation stripped just far enough back for the insulation to come in contact with the lug when fully seated, and preheat the copper wire slightly. Then I stick the cable into the melted solder and seat fully down . I hold for a couple of seconds and continue heating with the other hand. Then, before it cools, I use the vise jaws to "crimp" the lug slightly. Never had a problem.

[Burnit]

I solder my lugs on. I start by heating the lug in a vise with a propane torch, then adding rosin core solder about 1/3 -1/5 full and is molten. Then, I take the prepped cable with insulation stripped just far enough back for the insulation to come in contact with the lug when fully seated, and preheat the copper wire slightly. Then I stick the cable into the melted solder and seat fully down . I hold for a couple of seconds and continue heating with the other hand. Then, before it cools, I use the vise jaws to "crimp" the lug slightly. Never had a problem.

Hence the name "Lugweld"

[MAC702]

...My LWS said to use a larger lug and double the copper over for a better connection....

He must've read about that on the Internet. Precisely why I don't talk to these guys except to swap my cylinders...

[David R]

I solder them. I put the wire in, heat everything up. When the 50/50 resin (rosin?) core solder starts to wick up the cable,I take away the torch and top up the lug with solder till its full. It will go down a little as it cools. Never had a problem. We always did this with forklift battery connectors. I have not had one heat up or come apart. The cable should fit the lug in the first place. You have to get the heat right. Too much and it will wick WAY up the cable and too little it will be a cold joint.

Hmmm Get the heat right.......

Nothing against a good crimp, just the way I do it.

David

[farmersamm]

Well, here I go again

Is a round crimp, instead of mashing it flat, able to handle as much current??

Is it just a matter of how much copper strands there are in a given wire size??

And another thing I've wondered........... I see the crimps that are sold that just well... crimp. The outside shell is really thin. Then I look at a really nice Tweco connect or one from the electrical supply, and the whole thing, even the shell around the wire, is thick.

Doesn't the crimp thing have to be able to conduct as much as the wire is able to conduct? Seems that thin stuff is not enough for the amps.

I HATE ELECTRICAL STUFF

[wb4rt]

Well, I ended up buying a little manual crimper for under $10. It has a gauge on the side to judge when the crimp is correct. I used the right size lug, a number 4, instead of doubling it, and made a very good, strong connection.
I really appreciate all the good comments. That is why I check this forum at least once a day, unless I'm out of the country like last week. I have found this to be a good source of knowledge.
Thanks guys!

[David R]

My LWS has some heavy duty ones with a tit on them to hammer on. It works pretty good, but I still prefer solder.

Sam, I found the wimpy connectors like you are talking about will break from bending where the flat meets the round. I only use them on starters and stuff where the wire is held in place and will not move. I solder those too.

David

[JTMcC]

I don't double them, and I hammer them to a tight fit with, you guessed it, a hammer. Be carefull not to hammer the open end onto the cable as it will cut strands. But other than that I pretty much flatten them out, without getting rediculous.
Several years ago I Put new 4/0 leads and all new connections on about 9 or 10 old 600 amp Lincoln motor generators that were used quite a bit with the dials maxed out, for gouging old liners out of 250 ton and 300 ton haul truck beds, then used at about 600 amps running .120" NS3M wire to weld new liners in. Usually two shifts/day. It was a constant maintenance task to keep all connections in good shape, that type of service smokes them fast. Going to the method I mentioned above gave me connections that ran considerably cooler, and they lasted 8 or 10 times longer than any other method including using a store bought crimper.
That's my take.
Others will be along soon to tell you how stupid I am

JTMcC.

[David R]

you spelled stoopid wrong...

David

[Sandy]

Well I guess when the proper crimper runs minimum $2500.00 and the dies around $150.00 to $250.00, a hammer seems like an attractive alternative. Properly done a lug lasts well beyond the time when the sheathing rots off the cable.

Sadly enough the proper tools just aren't readily accessible to the guy, or gal, who needs a couple done.

[lugweld]

The hammer type crimper works fine. It trips downward when a hammer hits it putting a nice, round and thorough dent in the lug with out distorting it. I have used those for industrial battery connections without much problem. The issue with crimping a lug on is that for some reason, heat can build up at the point of the crimp. Soldering guarantees a smooth flow of power through the lug.

But for those of you trying to find an economical crimper, go to Lowes to the cable aisle and buy one of their ferrel crimpers that crimps the stops on air craft cable. They do a fantastic job on smaller lugs. Some stores have bigger ferrel crimpers. I believe they are around 40 bucks for one. If you can find one for the size you need, it may be more.

[JTMcC]

you spelled stoopid wrong...

David

Thank you for noticing

JTMcC.

[TEK]

I usually hammer them till they're snug, use a chisel with a blunt end and pound a groove in them, and then solder them....never had one fail...

[mark8310]

you spelled stoopid wrong...

David

He also spelled ridiculous wrong, but I ain't gonna tell him .....

Oh, btw,,,, I generally just use the hammer, also. Why get all uptight about a $2.00 copper lug????

[JTMcC]

The task ahead is large grasshopper.........if you intend to correct MY spelling oops's

JTMcC

[Oldiron2]

If you fellows have some heavier cables and really want to get fancy, they make (or used to) a kit with a mold into which the cable and lug both fit. The top part gets a powdered mixture (a 'secret' mix of Al and Copper oxide powders-Quiet; don't tell) which gets 'lit' and then reacts, producing molten copper which welds everything together. I have some canisters of the powder, but no molds. A different mold is needed for different sizes, of course.
I have seen a variation being used to attach grounding wires to railroad rails.
This is a variation of the old Goldschmidt reaction which is best known in the Thermite reaction for iron and steel.

[BNF]

I was always told not to solder the ends on, due to added resistance in the solder. Hence i use the beater method. Any truth to the solder story, or just repeated garbage?

[Sandy]

If you fellows have some heavier cables and really want to get fancy, they make (or used to) a kit with a mold into which the cable and lug both fit. The top part gets a powdered mixture (a 'secret' mix of Al and Copper oxide powders-Quiet; don't tell) which gets 'lit' and then reacts, producing molten copper which welds everything together. I have some canisters of the powder, but no molds. A different mold is needed for different sizes, of course.
I have seen a variation being used to attach grounding wires to railroad rails.
This is a variation of the old Goldschmidt reaction which is best known in the Thermite reaction for iron and steel.

Cadweld is probably what you've seen.

[Oldiron2]

That sounds familiar; I've probably seen the name in a catalog (or maybe on the box of little containers?)

[Sandy]

That sounds familiar; I've probably seen the name in a catalog (or maybe on the box of little containers?)

Yeh, depending on the size of the mold and all, the charge used to come in blue "pill" bottles and ususally in boxes of about twelve each. You buy different formula's of charge depending on the material make-up of the joint. The latest I've seen come in a plastic package and inside that plastic package were the dozen or so charges in containers with peel off tops and looked about like those pudding cups you used to see only larger. No large lettering tho.