Fire!! Never cover LiFePO4 with wood!!!

[ArthurEld]

Without oil it will gall and that could ruin the threads.

 

[HRTKD]

Any oil that remains behind has the potential to contribute to stripped threads. Slippery threads are bad. Thorough cleaning after tapping is critical.

 

[Hedges]

Damned if you're wet, damned if you're dry?
How would anti-seize figure into the equation?

(Something of a rhetorical question, but curious as to what your answer would be.)

 

[HRTKD]

Damned if you're wet, damned if you're dry?
How would anti-seize figure into the equation?

(Something of a rhetorical question, but curious as to what your answer would be.)

I've held off saying anything about that, but my opinion is that given the tendency of the threads to strip, I wouldn't be putting any sort of lubricant on the threads. Until it's dry, thread locker is a lubricant.

In a situation where the tolerances between the terminal and the fastener are tight - meaning very little movement and the fastener completely fills the terminal width - I don't see a problem. But if the fastener isn't wide enough to engage the threads completely, you're just asking for trouble by adding lubrication.

 

[cinergi]

It seems to me that pull-out force would remain unaffected by the presence of a lubricant -- so when using studs, I don't see how it would matter because you're not turning the stud to secure anything to the terminal, thus torque values remain unaffected. Am I missing something?

 

[Hedges]

It seems to me that pull-out force would remain unaffected by the presence of a lubricant -- so when using studs, I don't see how it would matter because you're not turning the stud to secure anything to the terminal, thus torque values remain unaffected. Am I missing something?

With excessive clearance, might help aluminum slide out of the way of thread on studs.
I think some thread lockers said OK with oil.
I figure epoxy might fill gaps, help apply force deeper into the grooves and increase strength.

With well-fitting threads, I think main issue of lubricant is lower torque to achieve a given force.
As you note, that doesn't count if you keep stud from rotating while torquing nut.

Either way, I would clean hole with solvent.

 

[HRTKD]

It seems to me that pull-out force would remain unaffected by the presence of a lubricant -- so when using studs, I don't see how it would matter because you're not turning the stud to secure anything to the terminal, thus torque values remain unaffected. Am I missing something?

I don't think it matters much if you're using a stud, bolt or screw. It's still upward force exerted against the terminal threads.

 

[garethb]

The cell casing is also positive at least on the Lishen cells and my cells were not wrapped properly at the bottom exposing the cell casing. Potential for a short there so something to keep in mind when building the housing for your packs

 

[Frank in Thailand]

Kerosine, in Dutch called "lamp olie" and "Petroleum" (lamp oil)
That's hard to get here, but Diesel should work the same.

I found that alcohol doesn't really clean a thicker layer of (old) engine oil.
Acetone... I guess that dissolve just about any fat from any surface.
Foam probably is a bad idea...
But for this, on aluminium, should be good!

 

[Frank in Thailand]

I don't think it matters much if you're using a stud, bolt or screw. It's still upward force exerted against the terminal threads.

It matter a great deal!!
With a bolt/screw you are applying the force in a twisting motion, a lot more stress on the threads.

With a stud you can more easy be sure you have all 5 or 6 threads that are available in your terminal.

A screw/bolt you need to be quite exact.
And if you need to have double bus-bar..
You already loose a thread.

 

[HRTKD]

It matter a great deal!!
With a bolt/screw you are applying the force in a twisting motion, a lot more stress on the threads.

With a stud you can more easy be sure you have all 5 or 6 threads that are available in your terminal.

A screw/bolt you need to be quite exact.
And if you need to have double bus-bar..
You already loose a thread.

I stand by what I said. If a bolt/screw is getting threaded to the 6th thread until force is exerted against the bus bar or cable lug, it should have the same holding force as a stud.

 

[Frank in Thailand]

These are my tools to use.
I have mostly faith in the 3 set.
The spiral one might come in handy for different tasks.
(Set 3-8mm)

What drill is best to use?
Are there "flat head drill"?
As I don't need to go deeper, just wider.

A few of these to prevent to go too deep:

 

[Frank in Thailand]

I stand by what I said. If a bolt/screw is getting threaded to the 6th thread until force is exerted against the bus bar or cable lug, it should have the same holding force as a stud.

Sure, and you are correct.

Except that the stress on the weak thread during fastening is totally different.
If it would be strong iron, studs won't make (much) difference.

Apply 4Nm in twisting motion, compared to only pulling, that's a huge difference.

Once it's in, 4Nm is 700 pound.
Absolutely correct.

With bolts some cells might survive
With studs most cells survive the mounting phase of the installation.

Friction is a force to reckon with!

 

[Hedges]

Are there "flat head drill"?
As I don't need to go deeper, just wider.

I use a bench grinder to convert a typical drill bit to flat.

A few of these to prevent to go too deep:

Set screws might slip.

If you cut a suitable piece of tubing (e.g. copper) and slip it over drill bit, you can adjust it in chuck to get desired depth. If chuck slips the hole would be more shallow rather than too deep.

 

[fafrd]

I use a bench grinder to convert a typical drill bit to flat.



Set screws might slip.

If you cut a suitable piece of tubing (e.g. copper) and slip it over drill bit, you can adjust it in chuck to get desired depth. If chuck slips the hole would be more shallow rather than too deep.

I have found it very easy to drill into this soft aluminum by hand in the drill press (no motor used).

And as far as drilling too deep, I measure out the depth I want to reach and place a ring of masking tape on my drill bit at that point. By hand, it is very easy to ease the drill bit down to that depth by turning slowly.

I am much more comfortable working this soft aluminum by hand rather than getting any electrical power involved.

The primary purpose of the press is to maintain a straight drill.

I’m still struggling to get the tapping process itself working smoothly and will try both tapping to bottom in the press (by hand) as well as tapping a few starter threads in the press and then removing the tap from the press to finish by hand.

I’ve not tapped any threads before and find working with this soft aluminum much more of a challenge than I expected.

Sometimes I feel as though I might as well be working with wet clay...

 

[Frank in Thailand]

If you have some old heatsinks, that is a good way to practice.

Thanks for the tip of using without motor.
I can take off the belt, and rotate by hand easy.

Perhaps even the thread can be done like this!

 

[Frank in Thailand]

Google tells me that to tap M8 you need a 6.75mm drill.(Or 17/64)

I ordered 2, mostly because a replace takes days.

At $2 per drill, Inc delivery, not bad

 

[HRTKD]

Google tells me that to tap M8 you need a 6.75mm drill.(Or 17/64)

I ordered 2, mostly because a replace takes days.

At $2 per drill, Inc delivery, not bad

Using the right drill matched to the tap is critical and I have to wonder if the cells we're getting used too large of a drill bit, which produced threads that were too thin.

My drill press has stops on the handle that let me drill down to a specific depth and no further. But I can see doing it by hand to avoid any issues.

 

[fafrd]

If you have some old heatsinks, that is a good way to practice.

I found 1/2” aluminum rod which is what I am practicing on now. Not ideal because it is round, but I have a V-shaped tapping guide that holds it flat.

But old heat sinks is a good idea (if I had any)

Thanks for the tip of using without motor.
I can take off the belt, and rotate by hand easy.

Perhaps even the thread can be done like this!

Yes, you can easily tap the thread by hand in the press. The challenge I have had is getting the tap back out without destroying the newly-tapped threads in the process.

But if you have any experience tapping threads in the past, you should have little difficulty, since you have a good idea of what to expect.

I’ve never done this before and the gap between my fantasy from watching YouTube videos and the reality I am encountering is my greatest handicap...

 

[Frank in Thailand]

I just ordered one of this for my electricity room.

It's halotron based, the new type, environmental friendly and safe for humans.

Price here is around $125,-

Naturally intended for class C electric fire, and safe for the equipment that is not damaged with the fire.

Normal powder fire extinguisher will kill all electronics, eats away the PCB lines....

It starts at 68C, mercury based valve.

In my smoldering MDF fire it wouldn't have started, but smoke detectors would have.
(Now they are installed)