Trojan short T105 terminals

[daletournier]

Originally Posted by Wotname

OK, managed to find time to a quick and dirty test of Loctite (243). Please note this is by no means a definitive test and more detailed testing is required to quantify the results.

My test shows it does increase the resistance of the mated thread interface, probably by an order of 15 to 20 percent.

In essence I made a test rig of two terminals, a steel bolt and three nuts. I passed 50 amps from a calibrated constant current source though the rig and measured the voltage drop across it (with a calibrated Fluke 179). First numbers were without any Loctite used and the second were with Loctite applied to the two nuts (at the top of the picture). This was done several times and the numbers averaged.

Without Loctite, there was an average voltage drop of 15 mV, with Loctite this increased to 16.5 mV.

What is unknown is the division of the voltage drop between the bottom terminal, top terminal and shank of the screw but I guess the terminals would be roughly equal and much more than the shank, thus my rough figure of 15 to 20 percent increase when Loctite is applied.

Does it matter? Maybe if connecting alligator clips to the nut but we aren't, the nuts hold the lugs on which supply the path for current.

[Wotname]

Originally Posted by daletournier

Does it matter? Maybe if connecting alligator clips to the nut but we aren't, the nuts hold the lugs on which supply the path for current.

Dunno if it matters; probably depends on which of the side of the fence you sail
I just wanted to know if Loctite made much difference to the resistance of the mated thread surfaces and it would appear it does. I probably wouldn't use it due to the possible contamination to the surface of the lug.

[ramblinrod]

Originally Posted by john61ct

We're not attaching devices with alligator clamps to the outside of the nut.

Again, the contact area is between the flat "donut" surface at the batt body at the bottom of the post, and the wide surface of the lug.

The role of the post/bolts' and nuts' threading is simply to torque down and hold the lug tightly with maximum area against that surface.

There isn't current flowing "through" where the nylon is.

The post and nut could be completely non-conductive.

John,

Every marine house or start battery I've ever seen with a threaded post and nut (1000s), is electrically conductive SS.

It takes no special circumstance or lack of maintenance for them to conduct electricity. This is the normal condition.

How much current is passed through this current path, is dependant on the comparative contact resistance of the 3 current paths I previously identified.

1. Bottom of lug and terminal base.
2. I.D. of lug and threaded post.
3. Top of lug, through nut, to threaded post.

Repeatedly denying reality, does not change it.

[ramblinrod]

Originally Posted by Wotname

OK, managed to find time to a quick and dirty test of Loctite (243). Please note this is by no means a definitive test and more detailed testing is required to quantify the results.

My test shows it does increase the resistance of the mated thread interface, probably by an order of 15 to 20 percent.

In essence I made a test rig of two terminals, a steel bolt and three nuts. I passed 50 amps from a calibrated constant current source though the rig and measured the voltage drop across it (with a calibrated Fluke 179). First numbers were without any Loctite used and the second were with Loctite applied to the two nuts (at the top of the picture). This was done several times and the numbers averaged.

Without Loctite, there was an average voltage drop of 15 mV, with Loctite this increased to 16.5 mV.

What is unknown is the division of the voltage drop between the bottom terminal, top terminal and shank of the screw but I guess the terminals would be roughly equal and much more than the shank, thus my rough figure of 15 to 20 percent increase when Loctite is applied.

Thanks for testing this.

In my opinion, your experiment procedure is sufficiently sound that results could represent that present in the actual situation under simulation, immediately after fastener tightening.

The average degree of change observed would not be a great concern to me. I mean any contact resistance increase is undesired, but 16.5 vs 15 mV is not likely to cause harm.

I would be interested in reviewing the raw data, especially the range of contact resistance measured (inferred by voltage drop), used to calculate the average.

Factors that may not have been considered in this test, are the possible different results between carbon and stainless steel, and changes in contact resistance over time, due to corrosion and Loctite curing.

It would be interesting as an add-on test, to measure the voltage drop across the assembly (with and without Loctite) at various intervals of time (assuming in a fairly temperature and humidity constant environment).

Normally one would want to test numerous samples (e.g. 20 of each) to detect for any anomalies that could skew results, but c'mon, we're just havin' fun here. ;-)

[ramblinrod]

Originally Posted by Wotname

Dunno if it matters; probably depends on which of the side of the fence you sail
I just wanted to know if Loctite made much difference to the resistance of the mated thread surfaces and it would appear it does. I probably wouldn't use it due to the possible contamination to the surface of the lug.

Hmmm, that would be another interesting add-on test.

What happens if the Loctite gets between the intended current carrying contact surface areas, and not just on the threads?

Anyway, I'm not suggesting you spend time testing you can ill afford or don't wish to do.

But if you are willing to do the tests, I am willing to review your procedures and results.

(I gotta go do boat work, or I'll never be retired and able to pursue interests like this.) ;-)

[john61ct]

Originally Posted by Wotname

Dunno if it matters; probably depends on which of the side of the fence you sail [emoji2]
I just wanted to know if Loctite made much difference to the resistance of the mated thread surfaces and it would appear it does. I probably wouldn't use it due to the possible contamination to the surface of the lug.

Your setup's design is passing current through the nuts-bolt connection itself.

Which has nothing to do with the current path on a lug properly terminated at a battery post; the post and nut could be 100% non-conductive without creating a problem.

[transmitterdan]

This is correct. A “proper” test would be to put the two wire lugs together on a threaded rod and tighten them together with a pair of the loctite nuts. You will find no measurable difference in resistance between the wires with or without loctite. Same goes for nyloc nuts.

[Stu Jackson]

Originally Posted by ramblinrod

>>>>>>>>>>>>>>>>>

Yup that manudacfurer recommends Nylocs over wing nuts. I don’t have an issue with that.

Nylocs would be way better than wing nuts in my opinion.
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

I remember a number of years ago when Maine Sail first brought up "retiring" your wing nuts from your battery posts.

I had been using them with lock washers for decades. No issues ever. Easy to tighten and check, never backed off, could remove them easily, set them aside, no tools required.

So, wadda I do but go follow the electrical guru and replace the wing nuts, post haste and pronto!

First time I have to get one of the lugs off the battery, what do I have to do? Get TOOLS out for what used to be a one armed paper hanger job. I loosen the nut. But dumbo that I am I drop the f&#cking tool on the blinkin' posts and SPARKY rears his ugly head.

OK, all you wing nuts out there! Yes, I am clutzy - NOT! I know how to use tools. Stuff happens...

I find it difficult to need to replace a good secure simple system with something else that needs tools (that can drop).

Dale's approach makes sense: keep it simple, keep it safe, check things regularly.

I'm glad I saved those wing nuts.

[ramblinrod]

Originally Posted by john61ct

Your setup's design is passing current through the nuts-bolt connection itself.

Which has nothing to do with the current path on a lug properly terminated at a battery post; the post and nut could be 100% non-conductive without creating a problem.

Cmon kids, obviously the purpose of the test was to prove that Loctite between the threads increased contact resistance. The protocol was adequate for that purpose.

If anyone wants to perform an alternate test to prove something else, be my guest.

One conclusion I can draw from the test performed is that significant current can be passed between a threaded post and nut, which confirms my hypothesis and rejects any notion that current cannot follow this path as a number of you have posted.

Time to stop denying reality.

[hzcruiser]

Originally Posted by ramblinrod

Time to stop denying reality.

Would that also be a good time to think about how you come across talking down to others?

[hzcruiser]

Originally Posted by Wotname

My test shows it does increase the resistance of the mated thread interface, probably by an order of 15 to 20 percent.

Well done for a quick test, Wotname, and thank you!

There should be no doubt at all that Loctite, or any other less conductive material, would increase the resistance if it's in the current path.

Maybe someone should inform CALB that they've been doing it wrong all those years! I just installed some more of them yesterday and the Loctite at the end of their fasteners reminded me of this thread. Here is the confirmation:

From:
CALB USA Inc. - Making a large order?

Every CALB cell includes the requisite nuts and bolts for installation. They are the correct size and thread for your cells and the bolts are partially coated in Loctite.

But as most of us agree, very little current is or should go through the fastener itself.

[DotDun]

Originally Posted by ramblinrod

Cmon kids, obviously the purpose of the test was to prove that Loctite between the threads increased contact resistance. The protocol was adequate for that purpose.

If anyone wants to perform an alternate test to prove something else, be my guest.

One conclusion I can draw from the test performed is that significant current can be passed between a threaded post and nut, which confirms my hypothesis and rejects any notion that current cannot follow this path as a number of you have posted.

Time to stop denying reality.

Time to stop spewing crap!

The current that flows thru the nut doesn't matter, the lug to post connection can handle more than the cable itself. It wouldn't matter if the nut is a total dielectric.

Stop this nonsense!

[ramblinrod]

Originally Posted by DotDun

Time to stop spewing crap!

The current that flows thru the nut doesn't matter, the lug to post connection can handle more than the cable itself. It wouldn't matter if the nut is a total dielectric.

Stop this nonsense!

Sorry gents, but if there is corrosion under the lug, there could be a lot of current through the post. I come across corroded battery terminals all the time. It isn’t a rare occurrence.

So if the post won’t support current flow under this condition the boat could be dead in the water. That would be bad in my opinion. Current flow through the post in this condition would be good in my opinion.

If you disagree, that’s fine, your as entitled to post yours as I am mine. But in doing so, if you make a mistake I reserve the right to call you on it, as you would me. If you don’t like that, well tuff.

[hzcruiser]

Originally Posted by ramblinrod

Sorry gents, but if there is corrosion under the lug, there could be a lot of current through the post. I come across corroded battery terminals all the time. It isn’t a rare occurrence.

That's absolutely correct, Rod. If there is corrosion under the lug, the current has to go through the stud, if there is no or less corrosion on the top side of the lug.

That doesn't make John's and .Dun's statement about the "possibility" of the stud being made of non-conductive material wrong, though. Even though we know they're not made of nylon or wood, it was just to re-iterate his point.

[daletournier]

Originally Posted by ramblinrod

Cmon kids, obviously the purpose of the test was to prove that Loctite between the threads increased contact resistance. The protocol was adequate for that purpose.

If anyone wants to perform an alternate test to prove something else, be my guest.

One conclusion I can draw from the test performed is that significant current can be passed between a threaded post and nut, which confirms my hypothesis and rejects any notion that current cannot follow this path as a number of you have posted.

Time to stop denying reality.

Of course it can but that it's not the path the current takes, it runs from the lugs to the cables. If there's a problem this isn't due to nylocs or loctite, this is due to poor maintenance at the terminals or loose connections . As mentioned by John the nuts could be completely non conductive. Their job is to fasten the conductive lugs to the battery not act as conductors (a path) for current to run through.
We are now going around in circles.