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Just my 2p's worth. I wouldn't 'actively' encourage the use of a Dsmb as a lifting bag as it could have serious repercussions as I nearly found out! I was on a club dive and came across a modern anchor that hadn't been down long, so without giving it a second thought we attached one of our dsmb's to it and sent it to the surface, I should also add that this was within the first five minutes of the dive and we were the only buddy pair in the water. Upon seing the dsmb on the surface, our boat cover asumed that there was a current and started to follow it as it was taken by the tide. There was only a slight current so we were able to stay on the dive site, so it was only after another 40 minutes that we put the blob up to end our dive. To our supprise, surface cover was still following the first Dsmb that we sent up. Luckily after a while we were spotted and picked up - we were lucky. In hindsight we should have sent up the second dsmb straight away. From that dive onwards I've always carried a lifting bag with me just for those occasions.

Irfon
 
Multiple DSMB's :teeth:

Depending on the weight of the shot, the first one will be full, so the dump is
alongside you. Pull that and enough gas comes out to make neutral into
negative. You can now pull it down and do the same for the other(s)
alongside.

Other way is attach a thicker cord to the hole in the top, so you can
pull it over and let ambient pressure do the rest.

Finally if you have to you can rise up 1m and just pull it over as
above. Once horizontal it doesnt matter where the dump is.

Jeeze it's almost like we've thought through this s*it :teeth:
Much easier with a bucket ;)
 
Just my 2p's worth. I wouldn't 'actively' encourage the use of a Dsmb as a lifting bag as it could have serious repercussions as I nearly found out! I was on a club dive and came across a modern anchor that hadn't been down long, so without giving it a second thought we attached one of our dsmb's to it and sent it to the surface, I should also add that this was within the first five minutes of the dive and we were the only buddy pair in the water. Upon seing the dsmb on the surface, our boat cover asumed that there was a current and started to follow it as it was taken by the tide. There was only a slight current so we were able to stay on the dive site, so it was only after another 40 minutes that we put the blob up to end our dive. To our supprise, surface cover was still following the first Dsmb that we sent up. Luckily after a while we were spotted and picked up - we were lucky. In hindsight we should have sent up the second dsmb straight away. From that dive onwards I've always carried a lifting bag with me just for those occasions.

Irfon
If you use a DSMB as a lifting bag for any reason then you will also
need a strop or solid clip to connect item to bag.

1. Any boat alongside even in bad viz would see webbing attached or
a single line attached. Seeing as the cargo is directly underneath its
easy to tell if its cargo or a single thin piece of cord.

2. An inert lump doesnt pull the blob, a diver on the end will either
pull the blob, it goes upright or have no tension, which usually means
it falls over. The blob dances on the surface and that makes it pretty
difficult to confuse with a permanently tensioned inert weight, where
the blob stays upright.

3. On the top of the blob you have a hole, attach a slate and tell the
boat what you've done. While you are setting up the strop, your buddy
can be doing this. Remember the blob will be under tension at all times
so this slate is 1m above the water and should be easy to see by any
boat alongside.

Bottom line is that any kit can be good or bad, the difference is the
thought that goes into making it good.
 
i lift stuff a fair amount, be it bags of lunchables, the odd anchor or discarded pot plus i am sorting some kit out for larger lifts of stuffs. with a50 kilo lift bag.


whilst a delayed works sometimes i have lost a few when it was simply not man enough to lift the bag. so costly lessions have taught me that its better to have to much lift than not enough.

attachment wise i use a double ender to clip delayeds to stuff i could use a simple carabiner but i have double enders on me anyway.

when i sort my big sack of snaffling out the lift bag is going to be pretty much perminantly attached to it.
 
Lifting bags are for lifting things and Surface marker buoys are for marking your position on the surface. There are plenty of boats I go on where you would get a bollocking for using a DSMB as a lifting bag and vice versa.

I teach a few steps to connect and put a bit of air in, before moving on to repositioning the shot.

After repositioning the shot, I then add enough air to make it neutral, then throw it up in the air and off it floats.

It's worth rereading the instructor manual on this one. There's also a mid-water DSMB in there as well.

Janos
 
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