PINNED - Lithium battery conversion/info

[Burgerman]

youtu.be/9rtiFBC0wms

[terry2]

youtu.be/9rtiFBC0wms

Good video.

I do have(some where) a 6MM helicoil tap and a finishing tap so the finished thread would go to the bottom.
And helicoil kit are very cheap these days.

[terry2]

youtu.be/u08XLjy6_Kc

[Burgerman]

If those threads in the cells were crap, used, not deep enough I would return them.

If not, I would likely helicoil all of them from te start. You can buy tangless ones too. Although I never saw one yet. No hammering. Use a drill press, be sure you TAP them in a drill press by hand turning to be sure its totally straight and accurate.. Use green thin loctite. THEN build pack better than new. I used to do this on bikes every time I built a motor. Better stronger threads than new.

[terry2]

If those threads in the cells were crap, used, not deep enough I would return them. If not, I would likely helicoil all of them from te start. You can buy tangless ones too. No hammering. Use a drill press, be sure you TAP them in a drill press by hand turning to be sure its straight. Use green thin loctite. THEN build pack better than new. I used to do this on bikes every time I built a motor. Better stronger threads than new.

tangless ones are the best to buy.
I have emailed him about the cells.
Lets see what he says. If they was drilled and tapped before being put together. I won't take a chance.

[terry2]

I have just ordered these just in case

https://www.ebay.co.uk/itm/253913755675
https://www.ebay.co.uk/itm/391217705295

[terry2]

Update from the supplier.

He said I can drill them ok, but don't go deeper than 7.5mm.

So that's my next job

I have a cordless drill and I ma trying to find a stand for it with no luck

[Burgerman]

Update from the supplier.

He said I can drill them ok, but don't go deeper than 7.5mm.

So that's my next job

Thats not enough. ANY blind thread must be 9mm deep minimum or its bad by design.
You need 9mm of thread minimum as thats 1.5x diameter. That means drilling 11mm and tapping with a bottom tap to 9mm.

And all the thread repair helicoils will be 9mm tall. https://uk.rs-online.com/web/p/thread-r ... s/0528659/

[terry2]

Update from the supplier.

He said I can drill them ok, but don't go deeper than 7.5mm.

So that's my next job

Thats not enough. ANY blind thread must be 9mm deep minimum or its bad by design.
You need 9mm of thread minimum as thats 1.5x diameter. That means drilling 11mm and tapping with a bottom tap to 9mm.

And all the thread repair helicoils will be 9mm tall. https://uk.rs-online.com/web/p/thread-r ... s/0528659/

I just checked one cell and a 10mm long bolt goes down ok.
So I will go with that.

[LROBBINS]

Drill size for an M6 helicoil is 6.2 mm. In soft aluminum you might get away with running a tap directly in the already tapped (and partially stripped) threads, but it might be safer to get a 6.2 mm bit and carefully drill first. M6 helicoils do come in 1d length too, but probably harder to find than 1.5d or longer. John is absolutely correct that you can't use a hand drill and even tappin is best done with a drill press (but by hand). You must turn it by hand (unless you have a fancy adjustable torque tapping machine) so you can feel when the tap just touches bottom.

Although the Al is soft, it's probably best to turn a bit and then back off the tap to break the chip, then turn a bit more etc. Perhaps if you've not done this before you can practice with a scrap piece of aluminum before risking the cells. Candle wax is a reasonably good lubricant for aluminum, but you'd need to clean it out with solvent if you use it. Aluminum is easy; if you tap stainless without breaking the chip often and best using a lubricant even for hand tapping, you'll break a few taps before you get a feel for it. Brass also tends to bind, but taps very cleanly if you're careful. Ever try removing a broken M3 tap from a blind hole? (For "large" sizes like M6 one can get removal tools for getting out broken taps - they have thin fingers that go down the flutes. I don't own any, but the machine shop where I learned to properly tap things did, and I've never seen one for M3.

[terry2]

Drill size for an M6 helicoil is 6.2 mm. In soft aluminum you might get away with running a tap directly in the already tapped (and partially stripped) threads, but it might be safer to get a 6.2 mm bit and carefully drill first. M6 helicoils do come in 1d length too, but probably harder to find than 1.5d or longer. John is absolutely correct that you can't use a hand drill and even tappin is best done with a drill press (but by hand). You must turn it by hand (unless you have a fancy adjustable torque tapping machine) so you can feel when the tap just touches bottom.

Although the Al is soft, it's probably best to turn a bit and then back off the tap to break the chip, then turn a bit more etc. Perhaps if you've not done this before you can practice with a scrap piece of aluminum before risking the cells. Candle wax is a reasonably good lubricant for aluminum, but you'd need to clean it out with solvent if you use it. Aluminum is easy; if you tap stainless without breaking the chip often and best using a lubricant even for hand tapping, you'll break a few taps before you get a feel for it. Brass also tends to bind, but taps very cleanly if you're careful. Ever try removing a broken M3 tap from a blind hole? (For "large" sizes like M6 one can get removal tools for getting out broken taps - they have thin fingers that go down the flutes. I don't own any, but the machine shop where I learned to properly tap things did, and I've never seen one for M3.

I have done it before but the tips will come in handy.

I will be doing it by hand as I can't find a drill stand for my cordless drill.
The helicoil kit with everything cost £8.50p

[Scooterman]

This is my drill Terry, it's been hammered but is still going strong, hopefully . (bigger cordless are too heavy for little 'ol me). https://www.ebay.co.uk/p/Bosch-GSB10-8- ... /215580665

But that's beside the point, why I mention it is that I looked for a drill stand for it but on checking out reviews, none were rated very highly. I did think of gluing a round 360 bubble level to the back end for vertical drilling, but didn't in the end, purely relied on eye (not great I do admit).

But one day I will buy a pillar drill either new or secondhand. I want a flat/house with a spare room or heated garage which I can kit out as a proper workshop instead of using a B&D workmate in the garden.

But if you buy a drill press let us know if it's any good.

[expresso]

Sounds like these can be a bit of a pain in the ass now - i am not very good at drilling etc, the screws i received are 14mm total and about 10mm trend part -

making me worry now

[LROBBINS]

If you don't have any kind of drill press, I'd try holding the 6.2mm in a T tap holder and really drilling by hand - you're only removing about 1/2 mm (the drill for the original M6 was 5mm or so) of soft aluminum. I'd avoid using that cordless drill in any case.

[expresso]

if space permits - would using the grub screws and locktite it down - with red instead of blue - then build ? doing this from the start - so it never gets stripped - this would be a problem if i had to do that procedure and for 16 cells - thats alot of work - one mistake and its ruined

[expresso]

https://smile.amazon.com/uxcell-Serrate ... 0X5XG&th=1

would these be any good along with grub screw and flat washer - little loctite on grub screw also ?

would seem very secure - if room permits

[Burgerman]

Yes, if the threads are healthy/new probably. But copper is weak and oxidises. Use brass. Or stainless steel. Or zinc plated.

But as long as you do not overtighten, and use correct length, on HEALTHY properly made threads then normal bolts are also just as good. If that thread is not 9 to 10mm deep then its already a problem as its obviously designed wrong, or threaded as an afterthought... I would still use green loctite if you choose threaded studs. Fit once and screw in tightish. Say 4nm which you can do by adding two nuts, tightened against each other to fit a spanner. Or get studs with an allen key slot on 1 end.

[expresso]

i dont understand all you mentioned - never used or know what a spanner is - etc, i am just trying to figure out options - which would be best - Green Loctite - is still removeable ? - only wrench i have for the headways are 5nm -

i would rather use allen head bolts and do it right into the cell as intended - but if there are issues from that - then the grub screw way was my second choice - giving i have the room - i didnt factor that in - never intended to use grub screws etc, may not be able either way - i have 1 1/2 inch of room - for wiring - has to be same as MK Gel 9.5 high no more

i dont think they are 10mm deep the treads - i could be wrong - my screw i received is 10mm the part that gets screwed down - but thats assuming you add the ring terminals and flat and lock washer as supplied - - if its a problem - then all these kind of cells will be a problem - other than the cells with the posts sticking up and screw nut down over it - instead of in it

[expresso]

supplied with the 100ah Cells

[Burgerman]

You measure the THREAD length. The part under the head. Where it says 'standard length'. Unless its a countersunk bolt.

Note, not related. The bolt look odd to me. Because it seems to have a left hand thread.

[Burgerman]

i dont understand all you mentioned - never used or know what a spanner is - etc, i am just trying to figure out options - which would be best - Green Loctite - is still removeable ? - only wrench i have for the headways are 5nm -

http://www.nfk.com.au/architectural-har ... ud-m6-30mm
THIS is a M6 threaded stud. In this case it also has an allen screw slot in the end so you can screw it in easily. In english, it is a Threaded Stud. In americanese you are calling it a Grub screw.
Green loctite is PERMANANT. Unless you heat it up. No other type is strong enough to solidly hold the stud so that it does not unscrew as you remove a Nut. A Nyloc M6 nut, and a flat washer should be used to hold the ring terminal(s). A m6 Nyloc Nut has nothing to do with Lugs because in english thats slang for EARS...
A spanner if what you call a wrench, in americanese. In english a wrench is a different tool used for pipework usually. And lugs are ears...
A spanner!!! https://www.amazon.co.uk/slp/metric-spa ... tckmq9969s

i would rather use allen head bolts and do it right into the cell as intended - but if there are issues from that -

There are NO issues with that. Unless you are not ending up with 9mm of thread (not tread, thats on tyres) as shown in the picture, above AFTER your terminals, and a flat washer. You want to use all of the thread, other than 1mm to make sure it does not hit the bottom so that it tightens up and clamps the ring terminal correctly. Any shorter, and you risk striping the soft threads in the cell.

then the grub screw way was my second choice - giving i have the room - i didnt factor that in - never intended to use grub screws etc, may not be able either way - i have 1 1/2 inch of room - for wiring - has to be same as MK Gel 9.5 high no more

You can use SHORTER threaded studs, and it should be only about 4mm total taller height, done correctly than using bolts.

i dont think they are 10mm deep the treads - i could be wrong - my screw i received is 10mm the part that gets screwed down -

Threads... The threads SHOULD offiially be minimum of 1.5X the diameter. That means 9MM is threaded. With a little extra say 1 to 2 mm at the bottom in reserve. Your vernier gauge has a thin bit that sticks out of the end designed for measuring this. And if you can screw in a 10mm long bolt ALL THE WAY then thats fine. If not then ad a washer and try again. If it now tightens properly measure the washer! Deduct that from the 10mm...

but thats assuming you add the ring terminals and flat and lock washer as supplied - - if its a problem - then all these kind of cells will be a problem - other than the cells with the posts sticking up and screw nut down over it - instead of in it

They dont have any idea what bolts or washers or terminals to use, or what you might use. Throw away their bolts, fit ones that use ALL of the thread, and that clamp your washer, terminal properly without actually bottoming out in the hole...

[expresso]

sounds more complicated now - having to figure out the correct screw size - means trying a few screwing in and removing - risk stripping

you dont think blue loctite is enough to hold the stud down and then lock nut on top and thats it ? if not removing the nut - it should be fine or else have to add more loctite again before rescrewing down the nut ?

i can say only from what i just did on the 80ah pack with a 10mm screw - ring terminal flat and lock washer - it felt good and tight that way -

if i had to guess - 10mm is good starting point - maybe even 12mm and add more flat washers worse case -

[Scooterman]

You can always do this if enough headroom. Stud, locknut, washer,lug, washer,nut, locknut. Locknut is just a phrase, doesn't need to be nyloc a normal nut locks down fine.

Just a suggestion.....

(Bottom locknut anchors stud into place)

[Burgerman]

sounds more complicated now - having to figure out the correct screw size - means trying a few screwing in and removing - risk stripping

NO risk of stripping at all because you do all your trial and error, careful checking, making sure the bolts threaded part is long enouh but not too long, by screwing it together with your hands, finger tight! Only when you do this on every connection, and are sure that theres enough thread length, and that it tightens up correctly without bottoming in the hole, do you touch it wih a tool of any kind.

Its a bolt.Its not some kind of rocket science. You just need to take a little care with thread length on EACH SEPERATE TERMINAL by trying it with care, looking what is happening, before attacking it like some kind of ape with tools.

[terry2]

This is my drill Terry, it's been hammered but is still going strong, hopefully . (bigger cordless are too heavy for little 'ol me). https://www.ebay.co.uk/p/Bosch-GSB10-8- ... /215580665

But that's beside the point, why I mention it is that I looked for a drill stand for it but on checking out reviews, none were rated very highly. I did think of gluing a round 360 bubble level to the back end for vertical drilling, but didn't in the end, purely relied on eye (not great I do admit).

But one day I will buy a pillar drill either new or secondhand. I want a flat/house with a spare room or heated garage which I can kit out as a proper workshop instead of using a B&D workmate in the garden.

But if you buy a drill press let us know if it's any good.

I can't find a stand for our drills, so I will have to go old style.

Get a bit of wood at least 2 inches thick.
With the drill you get in the helicoil kit, drill a hole as straight as possible.

This will be your guild

Once my bad cell goes I will helicoil it and post pics.

[terry2]

sounds more complicated now - having to figure out the correct screw size - means trying a few screwing in and removing - risk stripping

NO risk of stripping at all because you do all your trial and error, careful checking, making sure the bolts threaded part is long enouh but not too long, by screwing it together with your hands, finger tight! Only when you do this on every connection, and are sure that theres enough thread length, and that it tightens up correctly without bottoming in the hole, do you touch it wih a tool of any kind.

Its a bolt.Its not some kind of rocket science. You just need to take a little care with thread length on EACH SEPERATE TERMINAL by trying it with care, looking what is happening, before attacking it like some kind of ape with tools.

You talking about me again

He can get 14mm in length as that is the length of the whole bolt.

I have just been out and went over as many bumps as possible to see if my stripped thread one comes lose.

[terry2]

You can always do this if enough headroom. Stud, locknut, washer,lug, washer,nut, locknut. Locknut is just a phrase, doesn't need to be nyloc a normal nut locks down fine.

Just a suggestion.....

(Bottom locknut anchors stud into place)

Instead of using 2 nuts
He can use the nylon topped nuts.

[Scooterman]

attacking it like some kind of ape with tools.

[Scooterman]

I can't find a stand for our drills, so I will have to go old style.

Get a bit of wood at least 2 inches thick.
With the drill you get in the helicoil kit, drill a hole as straight as possible.

This will be your guild

Once my bad cell goes I will helicoil it and post pics.

I did once think of mounting a length of aluminium U channel (drill body width) vertically in the workmate (use spirit level). Then use it as a guide to slide drill body up and down in. It might have worked but i never tried it. It wasn't for my cells, it was for another job i was doing.

[shirley_hkg]

M4? Sounds dodgy! Might be OK if that aluminium alloy is hard enough. But it sounds a little small and weak to me.

Helicoils mean you end up with a M6 thread again, but it is steel/stainless steel.

So no room for error then. Stainless is the way to go.

Stud with Loctite , and flange nut for better contact.

Found this flange locknut in one go.