DSMB is flaccid upon deployment. Looking for tips.

[eightytwenty]

So I read that a semi-open DSMB will usually lie flat and look paritially inflated on the surface while a closed DSMB will stand tall and tumescent on the surface.

My semi-open does stand up well on occasion and then sometimes not …

It's my understanding that that's more of a function of line tension and SMB size. A taut line will help the SMB stand. From what I've seen, it is true that semi-closed units are more likely to lose gas when flopped over, but I haven't ever heard anything about them laying flatter inherently.

That being said, most semi closed units I see are comically large, and as a result flop over, because not enough gas is put into them, and the line isn't held taut.

 

[pauldw]

Diet Coke and Mentos.

 

[JohnN]

So today I am practicing deploying my DSMB. A few months ago in the ocean I had great success. I realize that it is a skill that needs to be practiced so I set aside some time to do so today. I was at a lake at 20ft. I unrolled the sausage and used the inflator to manually inflate it. I then held the spool and it shot up. After it stopped moving I tied it off and then at the end of my dive I surfaced. (I did the deployment at the beginning of the dive. After deployment I swam around and the surfaced) When I surfaced about 2ft of sausage was above water, the rest was just under the surface and folded.

So on my next dive I put in more air (using lungs) this time when I surfaced half of it was sticking out the water. I then submerged and tried to reel it in but couldn't as the buoyancy was pulling me up. I had to swim up to the DSMB and roll it from the top.

I tried different things but I can't the DSMB to fully inflate out of the water. I do have an overpressure valve so should I inflate it more? I only gave it two puffs because I learned that air expands but in this case it didn't expand enough.

Any help or advice is appreciated. Thanks!

Hawk Tuah

 

[Jai Bar]

Also, check that the smb is not leaking (from the seams, punctured and so on).

If it leaks, it will partly deflate and, depending on severity of leak, will not keep erected (or partially stand) at the surface after some time.

Unfortunately, there are far too many low quality smbs out there that fail at the seams after a few dives. Won't be surprised if many vendors buy cheap low quality and rebrand them with logo.

 

[Tassie_Rohan]

So today I am practicing deploying my DSMB. A few months ago in the ocean I had great success. I realize that it is a skill that needs to be practiced so I set aside some time to do so today. I was at a lake at 20ft. I unrolled the sausage and used the inflator to manually inflate it. I then held the spool and it shot up. After it stopped moving I tied it off and then at the end of my dive I surfaced. (I did the deployment at the beginning of the dive. After deployment I swam around and the surfaced) When I surfaced about 2ft of sausage was above water, the rest was just under the surface and folded

Any help or advice is appreciated. Thanks!

Were you deploying your sausage in warm or cold water?

When I deploy my sausage there's a huge difference in size depending if the water is warm, cold or freezing.

If you must deploy your sausage when it's freezing, (and such emergencies can happen) then make sure there is no one with a camera nearby.

Other helpful life tips later..

Cheers
Rohan

 

[NothingClever]

If marking your position is really important, shoot earlier while at your deepest depth to exploit Boyle’s Law.

I don’t think paying out extra line and using a bolt snap to control the slack is necessary nor safe. It’s prudent to keep one’s “work space” uncluttered.

 

[BoundForElsewhere]

If marking your position is really important, shoot earlier while at your deepest depth to exploit Boyle’s Law.

oh c'mon!

 

[OMyMyOHellYes]

My mind is starting to wander towards a competitive DSMB sport.

Is there a space for precision DSMB launching/targeting from various depths?

Like float an inner tube on the surface and see if one can pop a DSMB through it?

 

[NothingClever]

oh c'mon!

Shelly?