Question about Peli cases (seeking advice)

[JAA]

The cheap Lidl dry bags kept my drill bone dry for 2 months left in pretty wet conditions. Maybe one of the those? And of course a small amount of seepage and damp isn’t going to knacker the drill instantly as long as it doesn’t fully flood which might do.

 

[Benfool]

@Pitlamp are you in a wetsuit or drysuit?

Ive had some success in the past putting a drill inside my drysuit. Probably not ideal for a long dive as its a little uncomfortable, but it worked well for Whirlpool Rising.

 

[braveduck]

Thanks Stuart; that's very useful information.

One alternative option I'm considering is to make a dry bag out of neoprene and a section of old drysuit zip. We used one many times to get a drill through Far Sump in Peak Cavern (385 m / -8 m) and it never leaked. Someone is selling a second hand Peli for a reasonable price so I'll test that first.

You're right about diving being a big ask; I've spent a lifetime watching all sorts of "waterproof" items fail!

Make a dry bag out of a tyre inner tube and two clamps .

 

[Pitlamp]

Thanks Benfool - this is a wetsuit project though.

Interesting suggestion stuffing a drill into a drysuit!

 

[Pitlamp]

Make a dry bag out of a tyre inner tube and two clamps .

I've got a version of that somewhere; slightly different design; one end is very firmly cemented together, the other is double folded and secured tightly with snoopy loops. When I decide what drill to get it may or may not fit. In which case I may be on the hunt for a wider inner tube.

Dry bags are far simpler to achieve neutral buoyancy than rigid containers, which hold a lot more air - giving greater upthrust, so more lead is needed to balance the upthrust with extra weight. Then again rigid containers don't change their buoyancy with changing depth.

 

[hyweldavies]

One thought: how about in a dry-bag or even a sealed placky bag? That will keep the water out as there'll be no pressure difference. Can then be inside something rigid but not waterproof for protection

 

[braveduck]

I've got a version of that somewhere; slightly different design; one end is very firmly cemented together, the other is double folded and secured tightly with snoopy loops. When I decide what drill to get it may or may not fit. In which case I may be on the hunt for a wider inner tube.

Dry bags are far simpler to achieve neutral buoyancy than rigid containers, which hold a lot more air - giving greater upthrust, so more lead is needed to balance the upthrust with extra weight. Then again rigid containers don't change their buoyancy with changing depth.

Tractor inner tube if they still do them .

 

[Pitlamp]

One thought: how about in a dry-bag or even a sealed placky bag? That will keep the water out as there'll be no pressure difference. Can then be inside something rigid but not waterproof for protection

I've used polythene bags in the past for small items. The trick is to twist the bag tightly then fold it over itself and twist it again, then a third time if it's long enough, then secure it with snoopy loops. Yes - something to protect the bag is needed!

I believe the Bosch Uneo drill will go in a Darren drum but it's not powerful enough for the job in question. Shame, because a Darren drum will reliably not leak going through a 6 metre deep sump.

 

[pwhole]

For what it's worth, I generally hose down my drill with the kit-washer back at the Chapel if it's muddy (without the battery!), and I must have done that 50 times, with no issues. I know that's not total submersion, but these things are a lot more water-resistant than they might seem.

 

[Pitlamp]

Yes, it's the battery that's far more vulnerable to getting killed by water.

We did some experiments running sacrificial drills completely underwater, supplied by a cable from a battery above water. It never killed the drills but they just don't work submerged due to running too slowly when filled with an incompressible medium. (It's the motor which is most affected.) After submersion they always ran fine again.

 

[undergroundHP]

@Pitlamp I have a spare Peli 1550, you can borrow if you would like to try a bigger sized case?
I used a ammo box for my Makita SDS drill. Though I don't take it through sumps it seems to do well in damp caves.

 

[Pitlamp]

Thanks for your generous offer undergroundHP! Noted - but I've set myself a target of nothing bigger than a 1400.
There's a good chance I'll use an inner tube bag or a proprietary dry bag though.

Ammo boxes aren't usually successful in sumps. The increase in pressure causes the sides to bend inwards; the sealing surface only needs to bend in a few millimetres and the water pours in.

It's time some clever Chinese engineer came up with a drill-shaped version of a Peli case which would need less lead to make it neutrally buoyant. I wish . . . !

 

[Stuart France]

Whether an equipment case with a hinged lid is waterproof or not will depend on (at least):
1) how stable, precise and robust the hinge design is so that the lid is held equally tightly the case bottom all the way around
2) the complete absence of physical distortion to the lid and bottom arising from thermal issues of injection moulding machines
3) what the seal is made of, such as neoprene foam, hard nitrile rubber like a diving cylinder o-ring, and so on.

Now look at a Pelicase etc and try to imagine the stuff sat in front of you being seriously suggested as adequate for a demand valve clamp on to an diving cylinder. No I didn't think so. But you need air cylinder valve quality of air-tight waterproofness to get your drill etc through sumps.

Using drybags sound like a reasonable idea at first bearing in mind that the air inside initially will halve in volume at 10m depth etc. However, I've found that my dry bags develop little holes due to abrasion, simple wear and tear from the tackle bag they are carried in and the cave surfaces on which the tackle bag moves. They don't stay fully waterproof for long.

For the DYO water depth logging project, we're taking tools and parts into the cave in a gigantic size Daren Drum. This floats across the lakes and is not subjected to underwater pressure, but it looks robust enough to withstand it. Again, the robust design of drum lid, base, plastic screw threads joining these, and the o-ring which is set into the lid are going to be critical.

From an engineering viewpoint, I get the feeling that no aperture design that employs a hinge rather than a screwed-down tightened-up lid will result in a waterproof container.

 

[RobinGriffiths]

Probably talking out of my ****, but could the air bell principle be used. e.g. upside down kitchen bin, peli box at 'bottom', maybe some counterweight around the rim? Obviously passage would need to be as high as bin.

 

[Cantclimbtom]

Yes, it's the battery that's far more vulnerable to getting killed by water.

We did some experiments running sacrificial drills completely underwater, supplied by a cable from a battery above water. It never killed the drills but they just don't work submerged due to running too slowly when filled with an incompressible medium. (It's the motor which is most affected.) After submersion they always ran fine again.

Then you've half answered your own question? The drill gets protected by polythene bags etc as you described above.

But now you need a small peli case for the batteries

 

[Pitlamp]

Why is nowt ever simple?

 

[christopher]

I regularly transport a drill through a (very shallow ) sump, I use 2 kayak style dry bags, the outer one is a tougher type, then just chuck in a tackle bag, no issues as long as I'm careful sealing the bags, very easily punctured though, they only have to touch limestone and there's a pin prick sized hole

 

[ChrisB]

Home Bargains sell 20 litre roll-top drybags for £3.99 each. When we had a canoe pinned in a rapid the bags that performed best were those and Ortlieb at many times the price. You could put the drill in an ordinary plastic bag, then double bag that in the Home Bargains ones.

 

[Pitlamp]

Thanks ChrisB - I sometimes go past one of their branches so I'll nip in and check it out.

 

[IanWalker]

I tried some drybags from Aldi but they have not done so well. The surface roughness and rigidity of the fabric seems to prevent a good seal on the closure, and stiff material seems to prevent flex in the fabric, meaning it wears out on fold lines. Ortleib standard duty seems to work better in both respects.