why more than 60-100' of line for a DSMB?

[Edward3c]

In the early days of DSMBs I had 20m of line. Twice I got caught out when firing it off from 21/22m. After which I now maintain 50m of line, which was completely used on a 35m dive because of current.

Like all equipment, continuous practice is require. I send mine up around every 6 trips to maintain the skil.

 

[Ulfhedinn]

Got a link?

Halcyon Super Big Diver's Alert Marker, 6' long, Closed Circuit,

info@extreme-exposure.com

extreme-exposure.com

 

[Ulfhedinn]

Halcyon Super Big Diver's Alert Marker, 6' long, Closed Circuit,

info@extreme-exposure.com

extreme-exposure.com

Pricey.. might be able to find a used.. to save a few bucks

 

[inquis]

Halcyon Super Big Diver's Alert Marker, 6' long, Closed Circuit,

info@extreme-exposure.com

extreme-exposure.com

Wow, 52 lbs of lift. One breath from 160 ft., but I suspect most divers will look to an inflator hose to fill.

 

[admikar]

I have duckbill 1.2m DSMB with about 35m of line. Using regulator to fill it. Usualy shooting from 20m, but sometimes I wait until 10m. At 20m, it's not a big deal filling it up, but at 10, I exhale all the way and then fill it until it starts to pull me up. So far, never had issues with water ingress in any significant quantity.

 

[Divin'Papaw]

I keep a spool attached to both my primary and backup DSMBs with around 100' of line on them. I like to shoot them when I'm just leaving the reef/wreck and early on my ascent. I'm typically shooting them from 50-60'. 100' has always been enough. I typically dive where there is a good bit of current as well.

 

[Divin'Papaw]

Wow, 52 lbs of lift. One breath from 160 ft., but I suspect most divers will look to an inflator hose to fill.

I have that bad boy and yes, you don't want to try filling it orally. I have an inflator hose on my pony bottle. I use that for both my small and large DSMBs. Even with that it is tough to get the big DAM fully inflated.

 

[GF99/99]

I am actually one of the few that really likes the open duck bill bottom type SMB's.

But it is all personal preference and depends on the diving and your application.

Reason I like the open bottom style is I find them much easier and more controlled to inflate. I dive CC and generally almost only dive with trimix and deco bail outs (don't want to waste trimix to inflate an SMB). I also carry on an onboard 21% air 2l for wing inflation. The way I send up an SMB is I pull the SMB out unroll it attach my reel then hold that in one hand and grab my wing inflator/deflator and hold it up like I am going to deflate my wing but instead I place the open end of the SMB over the deflate and deflate my wing causing all the gas to fill the SMB. Now am still neutrally buoyant because all I did was transfer the gas from my wing to the SMB but I am holding the SMB. Now I can slowly and calmly hold the SMB in one hand and then slowly transfer the reel to the other hand check that the line is not entangled anywhere hold it straight out away from my body check that there is nothing above me double check that the line is free then when I am ready release the SMB and let the spool free spin between my fingers. The second you release the SMB you just inflate your wing again with that free hand and your good to go. Absolutely no rushing at all

I like this because it is very slow, calm, and controlled and gives you plenty of time to double check that your line is not tangled on you and your going to get yanked to the surface (and if your like me and you usually have 3-4hr of deco obligation this would be probably result to death) I often see people send up SMB's using the inflator hose method or the purge the reg into the opening method I am not saying this is wrong but it always seems to be a mad rush to fill it as fast as possible then release it be for it yanks you to the surface all while making sure the line does not get caught on you. The only exception is those little one-two breath inflation SMB's that you can basically hold down because there so small. Yes these work also but they are small and very hard to see by a boat it kind of defeat the purpose of having an SMB. Also if you are diving CC with a heavy unit 4 S80 bailouts and you have to hang in the blue on deco for 4 hours its nice to have a big SMB you can go a little negative and hang on your reel and not sink your SMB

But SMB type, reel type, and deployment method is all personal preference I am not saying my way is correct its just an available option.

 

[rongoodman]

Wow, 52 lbs of lift. One breath from 160 ft., but I suspect most divers will look to an inflator hose to fill.

If I'm someplace where I think I need to carry one I just add an extra LP hose with my Dive Alert on the end, long enough so I can keep the bag well away from me while inflating it. It stays clipped off on the left waist D-ring.

 

[drk5036]

The duck-bill is actually a "semi-closed" type and probably what those instructors meant. A true "open bottom" is awful and will invariably spill air and flop.

Right, this is what I meant.