Making Battery Cables

**jd1923** · January 7

Recently purchased a Victron SmartShunt and I did not want to do a fancy install, perhaps later once upon a Lithium upgrade, but for now the shunt will be physically close as possible to the negative battery terminal. They don't sell shorty 4/0 AWG cables, as far as I can tell, and if you need a bunch of different sized cables, you can cut lengths to your needs and save money buying bulk cable and battery terminals (lugs).

I installed the shunt last week to check it out, grounding it with two shorty 4AWG cables in parallel, because I had them on hand. Twas fine for the testing, but the cross-sectional area of the two 4AWG cables s is about 60% of one 4/0. Amperage capacity is directly related to the quality of the conductor (less resistance) and its cross-sectional area (more capacity).

Cutting 4/0 cable is not easy. When I install an 1800W inverter 3 years ago, I used 2/0 and was able to cut that with the cutters shown. This tool is a bit dull and beat up because of that, and no way it was going through the 4/0. I put the cable on the vise and used the metal hand saw. Saw just touching the vise so that the cable stays put. A new fine steel blade would be best, fine since this is only copper.

Today I crimped the shortest cable that I've ever made, only 5" long, hole to hole. The other thing is I customized it by turning the lug on one side 180 to the other side. This allows for a 1" height gain necessary to mount on the taller shunt (picture mounted later). I used Selterm brand tinned copper lugs, that are so big that the insulated wire between the lugs is only 1 1/4" long.

It is extremely difficult to get all the copper strands into the lug, due to the sawed edges. Hammer the ends as round as you can before you strip the insulation, and then just strip a little at a time.

I purchased TEMCo pure copper 4/0 welding lead "Made in the USA." The crimper tool is their brand too, that I had from last time. Some guys hammer this kind on crimper. But I prefer again using the vise. This is a tug! You'll need a strong extension bar to get the full crimp. The TEMCo HD crimp tool works great btw.

I ordered heat shrink tubing which came in the wrong size, so later on that. Cool thing is 3" of heat shrink will go lug to lug on a cable this short, will show that later.

**jd1923** · January 7

Using a hand saw to cut the cable worked for building one, got me through the day. Just put this one on my wishlist! Klein Tools 63041 Standard Cable Cutter, 25-Inch - Wire Cutters - Amazon.com

More pics --

**Geronimo John** · January 7

There are some learning curves with fabricating your own 4/0 cables. The below is the process that I have used successfully.

Specialty Tools Used: If I needed to purchase tools for a 4/0 AWG cable efforts, I would spend the bucks for that Klein Standard Cable Cuter and a Hydraulic Crimper (shown above), or the one like John Davies suggested some time ago

Amazon: TEMCO TH1818 Hydraulic Crimper

Summit Performance: Klein Tools Standard Cable Cutter 63035 (16.25” long)

4/0 Cable Fabrication Procedure:

I have found it very useful NOT to cut the copper bulk cable to length until AFTER you have completed the full lug insulation on one end. Failure to not do so will result in more cable wastage, and utterance of “Bad Words” as JD has mentioned occasionally.

That said, one "trick" I stumbled on to help with getting all the copper stranded cable strands into the lugs is related to how I strip, cut and insert the cable to the lug.

The amount of insulation to be removed varies by lug size and the length of the hole that your wire is inserted into. But for this description, let's say you want to have 3/4" of bare cable to insert into the copper lug. In this example I would:

If the bulk cable does not have a perfect “clean cut”, then carefully cut it square with the cable cutter.
Now mark the bulk cable with a paint marker ¼” from the end, and again at ¾” from the end.
Use a tubing cutter (or a fancier insulation removing tool) circle cut the cable insulation (only) at the two marks.
Only remove the ½” of insulation as you will be leaving that ¼” of insulation intact on the bulk cable.
With the ½” section of insulation removed, now you want to loosen the ¼”" band of insulation by twisting the ¼” band of insulation on the bulk cable. Leave it in place to manage the strands of copper.
Carefully done and you will have all the copper strands well managed by the ¼” band insulation on the end of the cut to length cable.
Use a bench vice to hold your 4/0 lug. Since you have broken the bond of the ¼” band section of insulation, you can more easily insert the cable into the lug by pushing it into the lug as the ¼” of insulation retreats in front of the lug. As the ¼” band approaches the end of travel, remove it and you can finish insertion by twisting the cable into the lug as you push it. Only twist in one direction.
Crimp the lug onto the cable.
Now cut the cable to length and repeat the process on the other end.

NOTE: Always purchase extra cable and lugs. There is a learning curve involved.

GJ

Edited January 7 by Geronimo John
Updated for clarity

**ScubaRx** · January 7

13 hours ago, Geronimo John said:

There are some learning curves with fabricating your own 4/0 cables. The below is the process that I have used successfully.

Specialty Tools Used: If I needed to purchase tools for a 4/0 AWG cable efforts, I would spend the bucks for that Klein Standard Cable Cuter and a Hydraulic Crimper (shown above), or the one like John Davies suggested some time ago

Amazon: TEMCO TH1818 Hydraulic Crimper

Summit Performance: Klein Tools Standard Cable Cutter 63035 (16.25” long)

4/0 Cable Fabrication Procedure:

I have found it very useful NOT to cut the copper bulk cable to length until AFTER you have completed the full lug insulation on one end. Failure to not do so will result in more cable wastage, and utterance of “Bad Words” as JD has mentioned occasionally.

That said, one "trick" I stumbled on to help with getting all the copper stranded cable strands into the lugs is related to how I strip, cut and insert the cable to the lug.

The amount of insulation to be removed varies by lug size and the length of the hole that your wire is inserted into. But for this description, let's say you want to have 3/4" of bare cable to insert into the copper lug. In this example I would:

If the bulk cable does not have a perfect “clean cut”, then carefully cut it square with the cable cutter.

Now mark the bulk cable with a paint marker ¼” from the end, and again at ¾” from the end.

Use a tubing cutter (or a fancier insulation removing tool) circle cut the cable insulation (only) at the two marks.

Only remove the ½” of insulation as you will be leaving that ¼” of insulation intact on the bulk cable.

With the ½” section of insulation removed, now you want to loosen the ¼”" band of insulation by twisting the ¼” band of insulation on the bulk cable. Leave it in place to manage the strands of copper.

Carefully done and you will have all the copper strands well managed by the ¼” band insulation on the end of the cut to length cable.

Use a bench vice to hold your 4/0 lug. Since you have broken the bond of the ¼” band section of insulation, you can more easily insert the cable into the lug by pushing it into the lug as the ¼” of insulation retreats in front of the lug. As the ¼” band approaches the end of travel, remove it and you can finish insertion by twisting the cable into the lug as you push it. Only twist in one direction.

Crimp the lug onto the cable.

Now cut the cable to length and repeat the process on the other end.

NOTE: Always purchase extra cable and lugs. There is a learning curve involved.

GJ

For anyone this is or is anticipating making their own battery cables this is all VERY GOOD advice. Learn from John's previous experiences (I had to learn from my own mistakes thru the years).

If you already have a $150 utility cable cutter, you're in good shape. If not, I have successfully used a band saw to make a nice, square cut in 4/0 cables. No band saw either, put on your thinking cap or get out your charge card. Remember, the goal is to get as smooth and square a cut as possible on the end of the cable.

I use a small tubing cutter to remove the insulation also, but his method of leaving 1/4' on the cut end is brilliant and I guarantee you'll be hard pressed to come up with a better solution for getting all the strands into the lug prior to crimping.

I bought a hydraulic crimper off eBay years ago. I paid about $35 for it. This is a tool I thought I would use a few times and then it would sit on a shelf in the shop for the rest of my life. Not so, I have used it dozens of times for various things. Need to make a pinched locking nut? A 10 ton press will flatten a nut if you're not careful. The fact that I have it makes it useful for many tasks that require a lot of pressure that are difficult to do other wise. I would not be willing to pay over $50. You won't find $150 worth of usage out of it, or will you? If you do, the $50 model will do it just as well.

A bench vise is a very useful adjunct to this project. If you don't have one already, you now have an excuse to build a shop...so you'll have a place to mount that new bench vice.

**jd1923** · January 7

Thanks @Geronimo John. Yes, crimping one end before cutting the other will help to keep all the copper strands in line.

The hydraulic crimper is certainly a nice tool. Too bad I did not think to purchase one a few years back when I bought this manual version: TEMCo Hammer Lug Crimper Tool - Crimps 8 AWG to 4/0 Battery & Welding Cables (Workbench-Mountable) - Battery Terminal Crimper - Amazon.com

I would say if you're truly in the business of making battery cables, neither of these are satisfactory. You'd need to spend more and get one with individually sized dies for each gauge. Note the one I have is only $17 and the TEMCo TH1818 is $90. The "hammer style" is rated up to the 4/0 size, and by using a vise the crimps came out really nice, as you can see.

They both have the same style crimping die, producing the same shaped crimp. The hydraulic version has one great feature, in that it can be used to crimp new lugs on existing cables in truck or trailer. This ability makes the cost it worth it, as I've only being able to make cables on my workbench.

**Geronimo John** · January 7

49 minutes ago, jd1923 said:

The hydraulic crimper is certainly a nice tool. Too bad I did not think to purchase one a few years back when I bought this manual version: TEMCo Hammer Lug Crimper

I agree fully. Personally I made that exact decision as I started out 20 years ago with a TEMCO Hammer Crimper. Still find it quite useful here in Hawaii on smaller stuff. But for use on our Trailer without a vice handy it was a no go for me. Especially I would have to borrow a vice. But I would never put a cheater bar on another's vice. So I went hydraulic.

DYI Pro': I am very open to loaning out my hydraulic lug crimper during the summer. I know it was really handy this summer while visiting MaxBurner and beyond. If interested PM me.

GJ

**jd1923** · January 7

14 minutes ago, Geronimo John said:

I would never put a cheater bar on another's vice. So I went hydraulic. GJ

🤣 Agreed. I must confess that I bent the handle on my vice just making these two crimps! Made a dozen 2/0 crimps and many 4AWG and the handle was fine. Like I wrote earlier, crimping a 4/0 lug is a real tug!

We have a couple of 4" vises here, that I inherited. I'm always looking on Craigs for a larger HD vise. Another recommendation, if using a vise run it all the way out, put a little wheel bearing grease on the main bolt threads, near the receiving end. Then run it in all the way, out again, and wipe off the excess. This will greatly reduce friction while tightening.

I am rough on my tools, as for me it's the job that counts. Been collecting tools since the 70s and have many tools, some dating as far back as the 30s!

**jd1923** · January 8

Thought I would take my own advice and lube the vise. I found this crazy long bolt on the edge of our property a few years ago, must be a 15" long, likely from the telephone co. If this is hard enough it will become my new vise crank handle. I love when I can repurpose parts saved along the way! 🙂

See what a "cheater bar" on a 4/0 lug can do!
Thanks @Geronimo John!

I'd have that new cable on the Oliver today, if the heat shrink tubing was here and it wasn't snowing today! Oh but, it will be sunny and nice soon again in the high country of Arizona.

**jd1923** · January 10

On 1/7/2024 at 3:35 PM, Geronimo John said:

But for use on our Trailer without a vice handy... GJ

GJ, ya know they make truck mount vises!
Amazon.com: Forward 1705A 6-Inch Hitch Vise Truck Bench Vise Mount Trailer Fits 2" Hitch Receiver : Automotive

**Geronimo John** · January 11

Not worth carrying around another 30+ pounds to be rarely used. I do carry a large and smaller vice grip, and can use my Anderson ball as a strong point if I need to whack something. But not toooooo hard of course.

GJ

**jd1923** · February 29

Recently, I received the best of battery cable tools! I did not have these tools when I added the Victron SmartShunt (to start this thread), so the hack saw and crimper/vise worked for one shorty cable. I'm working on my truck this week, adding a tuner and gauges set, new starter batteries and all new battery terminals. These tools will be in use very soon and again with a future LiFePO4 upgrade!

These are the tools I purchased but I didn't want to pay these prices! I wanted a die-based hydraulic crimper. The "Dieless" crimpers create a triangular-shaped crimp vs. the hexagon shaped crimp dies.
Klein Tools 63035 Cable Cutter, Utility Cable Cutter Cuts MCM Copper and 350 MCM Aluminum Cable, with Shear-Type Hook Jaws, 16-Inch Handles - Wire Cutters - Amazon.com
TEMCo Industrial Hydraulic Cable Lug Crimper TH0005 V2.0 (11 US TON) 10 AWG to 600 MCM Electrical Terminal Cable Wire Tool Kit with 32 Die Sets - Amazon.com

The 16" Klien cutter cuts cables up to 4/0 AWG like butter. When I looked at Amazon 3-4 weeks ago it was $90. Today at $68 is a good price. I found an eBay auction, where the seller had 4 of them at $52 ea. I bought one and the next day all 4 were gone!

Found the TEMCo TH0005 on eBay too, a "used-once" set. Seller had it on a 7-day auction, opening bid was $69. I contacted the Seller to see if he would offer a good buy-it-now price. I thought he would come back at $100 or something. He changed the auction to buy-it-now at the same $69 price, OMG! I bought it in a heartbeat. Paid for it on Sunday, shipped on Monday and received it Wednesday (yesterday). eBay can be this or that, often gets a bad rep. I started with eBay as a Seller 23 years ago and have sold 100s of old car parts, used sporting goods, etc. I buy used USA made tools very often on eBay. With a little time and patience, I saved over $150 on just these two items. Check 'em out!

Jim and Chris Neuman · February 29

Another vote for the hydraulic crimper with dies. The quality of the crimp is outstanding and far surpasses results you can get with a stab crimper. Really, there is no comparison, particularly in applications which might be wet or corrosive. Coupled with quality lugs properly sized for the wire, adhesive shrink tubing like that made by Anchor and you will get really professional results. I have used mine to rewire a number of boats that live in saltwater and am very impressed with the results ... particularly when coupled with tinned multi-strand wire like that market by Anchor. Available at West Marine and other marine supply outlets. Expensive components but you will not use all that many and the results are as good as a professional shop will provide.

**jd1923** · March 1

Made a few cable crimps today, in between a full day of working on the TV. More pics to follow after the TV new battery installation.

The first one shows the 4/0 cable and lug on a length of cable I purchased recently (looks way better after the heat shrink). I'm not installing 4/0 cable soon but wanted to work the new tool 🤣! The 4/0 die when crimped did not hold the 4/0 cable. It will depend on the lug, its thickness, etc. and often you will use one size smaller to finish.

Got all my truck battery terminals fixed today. The second pic shows a 2 AWG cable that will connect TV battery to the power panel (the fuse panel that delivers 12VDC to ALL vehicle circuits). The OEM cable is 4 AWG, but I had a length of 2 AWG in a parts drawer, so I made this second cable! Love working on this stuff!

**MAX Burner** · March 1

9 hours ago, jd1923 said:

Love working on this stuff!

Same here! Nicely done, Brother!

**topgun2** · March 1

I'm presently in need of some new 4/0 cables. But, given that I only need as few as 2 or as many as 4, and have never needed cable crimpers of wire cutters in this size before, it is simply cheaper to purchase the cables ready made.

However, THAT doesn't stop me from being VERY jealous. 🤑

Bill

**jd1923** · March 1

When I needed a short-as-possible 4/0 cable to attach the new shunt, I found the shortest I could buy was 1 foot. Another thing you can do when making your own is to offset the angle of the lug (can't buy these). Notice the pic of the 2 AWG cable above, where one lug is 90 degrees to the other. I built it that way because one side mounts vertically to the battery post and the other side mounts horizontally to the power distribution box.

Also check out the pic of my short cable above. I mounted the lugs 180 degrees to each other that gave me a 3/4" lift to mount on the shunt. @topgun2 since Twist and our hull 113 are cousins, send me a PM if you want me to make you a couple custom 4/0 cables, at cost to your specs.

**topgun2** · March 1

@jd1923 thanks so much for the offer!

It will be a couple of weeks before I get another chance to go out to the storage yard to get any idea of exactly what I'll need. I'll let you know what is going on just as soon as I know.

Bill

**Geronimo John** · March 6

On 3/1/2024 at 10:40 AM, jd1923 said:

When I needed a short-as-possible 4/0 cable to attach the new shunt, I found the shortest I could buy was 1 foot.

For the negative terminal to the Shunt, many of use 1" copper bus bar. Cheap at Amazon.

**johnwen** · March 6

On 1/7/2024 at 3:03 PM, ScubaRx said:

If you don't have one already, you now have an excuse to build a shop...so you'll have a place to mount that new bench vice.

Now that would be a challenge for us! Tailgates don't count lol.

John

GarryandKristi · April 7

On 3/6/2024 at 3:53 AM, Geronimo John said:

For the negative terminal to the Shunt, many of use 1" copper bus bar. Cheap at Amazon.

and much easier to “fabricate”.

**Geronimo John** · April 7

Both MaxBurner and I (And several others) use this bar from out negative Litho battery bank to a BlueSeas Master Switch, and then to the shunt.

I copied the buss bar idea from another owner here on the forum.

GJ

Making Battery Cables

Recommended Posts

Link to comment

Share on other sites

Link to comment

Share on other sites

Link to comment

Share on other sites

Link to comment

Share on other sites

Link to comment

Share on other sites

Link to comment

Share on other sites

Link to comment

Share on other sites

Link to comment

Share on other sites

Link to comment

Share on other sites

Link to comment

Share on other sites

Link to comment

Share on other sites

Link to comment

Share on other sites

Link to comment

Share on other sites

Link to comment

Share on other sites

Link to comment

Share on other sites

Link to comment

Share on other sites

Link to comment

Share on other sites

Link to comment

Share on other sites

Link to comment

Share on other sites

Link to comment

Share on other sites

Link to comment

Share on other sites

Create an account or sign in to comment

Create an account

Sign in