Battery Terminal Replacement: Hydraulic Crimp - Die Size

JHZR2

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My Ram doesn’t have great battery terminals. Over the years and hundreds of thousands of miles, the batteries have been replaced multiple times, and probably over tightened.

56A87EE4-14CD-4F11-BDB0-C4FD01D0E999.jpeg


I’m changing to crimped on copper lugs, and military-style terminals.

On the truck, the negative cables are 1/0, the cable that goes from the one battery to the other is 1/0, and the cable that goes from that battery to the starter is 2/0 (the starter is rated at 2.7kW.

A friend has a hydraulic crimper, just some cheap thing that is rated for up to 2/0 cable. Something like this:


It has dies that are interchangable to make a hexagonal crimp. It has a 70mm die and a 50mm die.

2/0 AWG is 70mm^2
1/0 AWG is 55mm^2

There is one page of instruction that comes with the thing. It’s not really useful at all.

I tried the 70mm^2 on the 1/0 with a copper lug. It’s tight and secure, can’t really know if it’s “tight enough”. Too tight of a crimp, and you extrude the stands - not good.

I’m assuming the 70mm^2 is for the 2/0; since there is no 55mm^2, any concerns with using the 50? Should it be shimmed to stay open a bit?

Thanks!
 
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california

Fold over many layers of aluminum foil and compress on dies that are slightly too large for the lug. There can be that sliding card moly effect that can make beautiful looking crimps. Dont feel you need to use all the crimping force available.
Avoid crimp ears.

.
 

JHZR2

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Never seen anything like what you will be doing. Please post some pictures of when it’s done so I can understand what’s going on lol.

Not a big deal. Cut the cables at the old, broken terminals. Strip, clean with emory cloth, a ss brush, and electric parts cleaner, then crimp a new terminal on. It’s a lug, so you can bolt it to any battery terminal that the cable bolts to. I’m using the military style.
 
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25,117
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MA, Mittelfranken.de
My Ram doesn’t have great battery terminals. Over the years and hundreds of thousands of miles, the batteries have been replaced multiple times, and probably over tightened.

View attachment 34713

I’m changing to crimped on copper lugs, and military-style terminals.

On the truck, the negative cables are 1/0, the cable that goes from the one battery to the other is 1/0, and the cable that goes from that battery to the starter is 2/0 (the starter is rated at 2.7kW.

A friend has a hydraulic crimper, just some cheap thing that is rated for up to 2/0 cable. Something like this:


It has dies that are interchangable to make a hexagonal crimp. It has a 70mm die and a 50mm die.

2/0 AWG is 70mm^2
1/0 AWG is 55mm^2

There is one page of instruction that comes with the thing. It’s not really useful at all.

I tried the 70mm^2 on the 1/0 with a copper lug. It’s tight and secure, can’t really know if it’s “tight enough”. Too tight of a crimp, and you extrude the stands - not good.

I’m assuming the 70mm^2 is for the 2/0; since there is no 55mm^2, any concerns with using the 50? Should it be shimmed to stay open a bit?

Thanks!
I use a hydraulic crimper for 1/0 with the 35 (it may be different from the one you are using), do a couple of test crimps then cut the connector in half with a hacksaw. I use fine strand copper if that makes a difference, the 35 crimps it solid but no breakage or damage to the strands.
It appears there is not much uniformity in sizing, that is why I did crimps with different sizes unit I found the one that gave the nicest crimp regardless of the number on the die.
 
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3,364
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Roanoke Virginia
Not a big deal. Cut the cables at the old, broken terminals. Strip, clean with emory cloth, a ss brush, and electric parts cleaner, then crimp a new terminal on. It’s a lug, so you can bolt it to any battery terminal that the cable bolts to. I’m using the military style.
Oh ok makes more sense now. Thanks
 

X15

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The manufacturer of the terminal should list the correct size die to use with it, it's entirely dependent on the terminal design, there's no rule of thumb.
 

JHZR2

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The manufacturer of the terminal should list the correct size die to use with it, it's entirely dependent on the terminal design, there's no rule of thumb.

Yeah, this is some piece of junk eBay thing, the instructions say nothing and are the poorest English you’ve ever seen.

I have seen the product of this crimper, which to my eye looks good (never cut one in in half, to Trav’s point, which would be the correct thing to do, but I don’t have any stock of OE wire to test on).

There may not be a rule of thumb, but Ive also observed that the AWG/mm^2 values are known, and the wall thickness of terminals don’t vary by more than a fraction of a mm... so amidst a die sized for 50 or 70mm^2! I can’t see that there’s a huge difference. Key is to avoid over crimping.
 
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When I made the test crimps I looked for "winging" or pulling back of the insulation behind the connector and other signs of over crimping, I was looking for a solid mass with no air gaps.
#50 should have done this with a slight over crimp but it didn't, the #35 did it perfectly well but that should have been way over crimped.
My brothers #35 is smaller than mine, that's why I said there doesn't seem to be much consistency in these cheap buggers.

1/0 with a #35 crimp.

IMG_0583.JPG





IMG_0584.JPG
 
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Messages
2,117
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california
I've owned the HF Crimpers shown in that marine how to link I posted in #2, for many years, it has the same black dies show in in the MHT article, not the newer larger chrome colored dies that it and similar tools come with.

I recently acquired the FTZ leverage crimpers, as I had dozens of 2/0 cables to make, and the HF does only 4awg max.

5 years ago, I needed to make many 2awg cables with thick walled lugs. I ground out and filed a larger hex into the dies.

It was kind of a mystery how big of a hex to grind out, and each practice crimp wastes about 2.50$ of thick walled ring terminal/lug.

I felt I went a bit too far, grinding/filing too big a Hex and on the 2 AWG crimps, would fold aluminum foil into strips just over the width of the Die and have one layer in between each die half and the already crimped lug, and crimp again. The aluminum fol peels off easily from die or lug and the crimp would look awesome, and was not heating passing 100+ amps for 5 minutes

Making the 2/0 cable with the FTZ crimpers, which compresses in a square vs a Hex, using the prescribed die sizes for the thick walled lug being crimped. The amount of compression, diameter reduction, made me think I was undercrimping them. It also took about 60% less upper body strength, to crimp the flared starter lugs, compared to the thick walled lugs

But this is in comparison to the hydraulic crimps I have achieved with the very imprecise and clunky HF crimper.

The FTZ leverage crimpers, also took about 60% less upper body strength, to crimp the 2/0 flared starter lugs, compared to the 2/0 thick walled lugs after selecting the prescribed dies.

Which makes me believe I possibly heavily overcrimped with the 8 tons of hydraulic clamping force, even when avoiding the crimp ears, as the FTZ leverage crimpers are a professional tool., and have only 4 tons of force.

Yet no Crimp has failed, but I have not tested each and every one for heating when it is amp passing high amperage for a duration.

There is a desire to make the Dies touch with the hydraulic crimpers. When one is using metric dies on AWG and the dies sizes are questionable at best, Start with larger dies, and work one's way smaller. The tin foil sliding in the dies along that compressing face, is obvious when moving the lever compared to when it is not there.

I think the hydraulic crimpers allow one to easily go too far. Perhaps some digital calipers measuring the total length of the crimp terminal, will tell one when overcrimping/stretching/distorting lug and wire, is just beginning to occur.

I have used original battery cables to attach new terminals to, having to cut back 4 to 6 inches of wire before it was no longer black brown or green with corrosion/oxidation. A new brass brush and Caig Deoxit cn make the outer copper stranding look almost as good as new, but the interior stranding remains much less copper colored.

Some cables are just not worth attaching a new terminal to, but perhaps the few seconds a starter motor requires, the extra resistance is inconsequential to function.

Passing 100+ amps for an hour is a different matter.
 

JHZR2

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I got through it pretty successfully.

I used the 50mm die to tighten up the 1/0. Before:

BFC09360-1255-4358-B6E6-812CDB95F80E.jpeg

90840F88-E557-4DC2-9DF7-43700D11B473.jpeg


After, they were just compressed more. I didn’t close the 50mm fully on any.

9F27F497-1557-4A6A-96AD-E3B4669B2E3E.jpeg


Used the 70mm on the 2/0, closed fully, and I crimped twice.

433272F6-12C9-4297-95BD-7C77EA9B5DAD.jpeg

41542BDD-017C-415F-BBA5-F87D1F659ADD.jpeg
72199420-85FD-403F-BE5F-3801C49B76EC.jpeg


packed any spots where I saw wire with dielectric grease (mainly a concern on the OE paralleling cable), and shrink wrapped everything.

DF1C1967-33D3-4D80-9122-A6E5E6A4B42D.jpeg
9E94E0A6-9D80-4324-A614-31F327FE8145.jpeg
B3FADC0D-3CC2-442E-AB33-36007F3AE774.jpeg
D5395EC0-7BF8-4F94-AECC-B8FC3F286168.jpeg
 

X15

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Which makes me believe I possibly heavily overcrimped with the 8 tons of hydraulic clamping force, even when avoiding the crimp ears, as the FTZ leverage crimpers are a professional tool., and have only 4 tons of force.

Yet no Crimp has failed, but I have not tested each and every one for heating when it is amp passing high amperage for a duration.

There is a desire to make the Dies touch with the hydraulic crimpers. When one is using metric dies on AWG and the dies sizes are questionable at best, Start with larger dies, and work one's way smaller.


When using the correct dies in a hydraulic crimper the dies should touch, it's the size of the opening in the dies that determines the compression of the terminal. The tons force of the crimper has to be at least as much as is required to fully close the dies, going over is not a problem, going under is.
 

X15

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27
I got through it pretty successfully.

It's hard to tell from pictures, but yeah, the big crimps look good.

As for the little 10-12AWG Yellow ring terminals, just an FYI, the insulation of the wire should fit under the yellow insulation of the terminal. Only strip the wire far enough that there's a little bit sticking out of the wire barrel of the terminal when the wire is shoved all the way into the terminal.
 

JHZR2

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It's hard to tell from pictures, but yeah, the big crimps look good.

As for the little 10-12AWG Yellow ring terminals, just an FYI, the insulation of the wire should fit under the yellow insulation of the terminal. Only strip the wire far enough that there's a little bit sticking out of the wire barrel of the terminal when the wire is shoved all the way into the terminal.

Agree. Some already had some poor terminals on them, I left them alone. Others I could pull the terminals off or cut at the terminal, and still had a lot of stripped wire exposed. I may deal with some of those small wires more...
 
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When using the correct dies in a hydraulic crimper the dies should touch,...

I agree, however, Proper size dies for the Lugs and cable are the issue with this tool, as they are metric dies, and SAE cable and AWG lugs, so the exact proper amount of material to make the perfect crimp in the provided dies, is unlikely to occur.

SAE gauge is 6 to 12% thinner than AWG cable

So one can step down in die sizes, and judge when the cold weld has formed and not slam the dies completely closed.
It is easy, with this tool, to squeeze copper out the sides as if it partially molten, and this is undesirable, obviously.

With no previous experience using this specific clunky imprecise tool, JHZR2 did good to ask, and the result looks professional enough.

It's about a hundred times better than a hammer crimper, and a hammer crimp is a thousand times better than crushing the terminal in some vice grips, which seems to be the chosen method in the third world.
 
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If you can solder water pipes, you can solder the assembly together. It would be far better to solder your connections. I use welding cable and solder on my terminals and clamps. I do not care for mechanical crimp or bolt on connections attaching the cable to clamps and terminals. When you start hanging lines off the battery clamp bolt, it makes for a very unprofessional job and a source for future problems.
 

JHZR2

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If you can solder water pipes, you can solder the assembly together. It would be far better to solder your connections. I use welding cable and solder on my terminals and clamps. I do not care for mechanical crimp or bolt on connections attaching the cable to clamps and terminals. When you start hanging lines off the battery clamp bolt, it makes for a very unprofessional job and a source for future problems.

From what I’ve seen, this has generally been debunked. Relying upon solder alone is in itself a risk for a number of reasons. First, getting enough heat in to truly allow the solder to flow and fully wet all of the wire strands is hit or miss in any sort of DIY situation. Second, with the heat generated on an engine crank (my starter is 2.7kW, and the grid heaters pull a sustained 200A afterwards in cold weather), a connector that is soldered only can melt the solder and lose adhesion to the lug. Solder can also,crack over time..

A mechanical connection is definite. Especially if the approach is validated like how @Trav showed. I didn’t have the spare cable with identical strand count and size to do it, but that would have been best practice. Notionally a soldered and crimped connection is beneficial, but the solder doesn’t necessarily impart any electrical conduction. A tinned copper wire is another option that may have benefit, but Imwas not changing the wire from OE.

In general I might not use these military style terminals, but this truck comes with so many leads as OE, not to mention the aftermarket trailer controls and whatnot... that they were the best bet. I was considering marine/dc batteries that have a terminal and a threaded lug, but the fit of everything wasn’t as good. I still would have had to make up the lugged connections. Dubious someone could crimp these all together in an OE style design without a full replacement of all cables. That wasn’t in the cards here.

I do need to verify if there’s a torque spec for the 3/8” bolt that holds all the connectors. Not all terminals fit on then, so a few went on the tightening bolt, but that’s not uncommon with other style terminals anyway.
 
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