Strange triangular security bit - any ideas what it may be called?

[Chris Green]

I am trying to get into a cordless battery case without destroying it.

As far as I can see (they're down rather deep holes) the anti-tamper screws that hold it together have triangular socket heads but with extra difficulties added.

I.e. they are basically triangular (about 2mm or 3mm sides) but with a little lump on each side plus, I *think* a pin in the middle like security torx and hex bits.

Has anyone seen anything like this and does it have a name so I can buy a driver?

I can't take a picture because, as I said, it's down a rather deep hole (so it has to be a dedicated driver, 1/4" hex bits won't fit down the hole.

[Colin Bignell]

Have you tried finding them on the Wikipedia page?

[alan_m]

And if you can identify

I have a set but a warning. The hex shaft may/will be too large to go down a deep hole. A couple of my bits have been ground down, on a grinding wheel, to reduce the diameter of the shaft, or just to knock the corners off from the hex section.

[Chris Green]

I have now, it was interesting reading but there's nothing obviously like my screws appear to be.

[Chris Green]

I already have security bit sets with at least those 32. I originally thought mine were tri-wing but they're not. I have a long bit set with round shafts which are able to get into smaller holes than 6.3mm hex ones, these fit down to my screws but don't engage.

[ARW]

Not sure if it will work for you, but in prison you make your own security bits buy melting the end of something plastic (usually a toothbrush but you need something slimmer) and placing it over the screw.

[Chris Green]

That's actually quite a clever idea as, in this case, it's very difficult to see what's downthe hole.

Given that this is a very low priority round tuit I can waste time quite happily for a long while without getting annoyed by it.

Ultimately I can hack the battery case open with a Dremel saw or similar.

[rick]

[rick]

Here is a pack of 5 sizes of triangular bits

[Chris Green]

Yes, I know I can get simple triangle bits, that really isn't the problem.

1 - The holes are too small for 6.3mm Hex 2 - I think there's a central pin like in Torx security bits

[Richard]

These?

[alan_m]

Some Youtube suggest that some triangular security screws are easily removed with a torx bit.

[newshound]

Neat idea. You can also buy plastic moulding compounds that set fairly hard.

Alternatively I wonder if Woods' metal / Cerrobend would work?

[Jeff Layman]

Fascinating. If that is what the OP is referring to, I see they offer a screwdriver to fit at

I'm not sure it would fit as it seems to have the same diameter as a hex bit.

Only $45.65 each!

[Chris Green]

They certainly pretty close to what I can see, the M3 ones would be small enough.

The only problem is that I suspect that the bits to drive them are

6.3mm hex and that definitely won't fit down the hole (see the 'screwdriver' is "SRD-6.35" for all of them with different bits for different sizes). Yes, scroll down.

However I can look for SRSAB-3 and/or SRSAS screws.

Thanks!

[Tim Lamb]

Or hot suitably sized plastic knitting needle to get the shape. Bit of appropriate diameter mild steel bar. Hole drilled to take the pin and the end ground to match the socket.. Bend the bar end for leverage or use your nearest set of water pump pliers:-)

Consider the satisfaction of finding work for the most commonly mentioned d-i-y tools!

[Thomas Prufer]

Sometimes a small slotted screwdriver will fit in the recess "somehow", between the lobes and the pin...

I have gotten lucky and a) reached far down enough and b) mamaged enough torque to remove the screw, and sometimes c) the central security pin breaks off allowing a different tool to to fit.

In all cases, dig out the box of assorted scres wand find a reasonably-headed scree to replace the security one.

Also you can take a short bit, grind it down --which will be less material to remove because it its short-- and dremel a slot in the back end. Drop bit in, turn with slotted screwdriver, hope for result.

Thomas Prufer

[alan_m]

If a torx bit can be used to remove a triangular holed screw perhaps the torx security bit with the centre hole may remove these?

Youtube also shows triangular holed head screws being removed with a small straight blade so to get over the raised muddle perhaps a security pin bit may also work?

[Theo]

'Tri-lobe with pin' or 'Three lobe with pin' seems to be the description for these.

Pentalobes are common due to Apple, but trilobes seem less so.

For smaller screwdrivers the standard interchangeable bit size is 4mm, and the bits are often longer in proportion so will go down deeper holes.

What make of battery is this? Perhaps somebody makes a special tool for opening them?

Theo

[Chris Green]

I'll try that then, thank you.

It's a pretty generic one from Ali Express for a Metabo drill. I've cut the old Metabo case (with almost dead batteries) open. The replacement fits the Metabo charger but not the drill so I'm looking at ways to either adapt the case so it fits or, if the worst comes to the worst, putting the new batteries in the old case and gluing it back together.