Which signal tube do you prefer for technical diving?

[serrada]

Closed is completely closed and is inflated by blowing through a valve or inflating it with a low pressure type hose. The kind you attach to your bc.

Semi-closed has an opening on the bottom where bubbles can freely come into the SMB, but it has a flap (unlike and open SMB) to keep the air from dumping out on the surface.

Halcyon has examples of each type.

 

[DA Aquamaster]

IMO an open spool is highly unsuitable for deploying a DSMB and I wouldnt even consider using one. Nor would I use a semi-enclosed reel with a friction lock. The first is extremely prone to entanglement, the latter rather less so, and neither will lock in any given position. Each has valid applications but this isn't one of them. Only an enclosed ratcheting reel is safe to use.

That is an interesting point of view that I don't share.

With the exception of the gentleman above wrapping his thumb in the line, a spool is essentially idiot proof as long as you rememember to hold it in a manner that does not allow line to unwind and to hold it out with the line in tension straight to the bag when you launch it - neither is hard to do with a small amount of practice.

Reels vary and some are great while others truly suck. Personally, I prefer an open reel with a side handle design and a plastic screw that mates against the rim to create friction. The amount of friction is adjustable and more than adequate to lock the reel in a given position. And with the side handle deisgn you can alterantively coontrol the dragw ith your finger tips or the ball of your thumb to prevent any back lash when the bag surfaces. I prefer that to the mechanical complexity involved in most ratcheting designs.

Similarly, I am not a fan of enclosed reels as while they seldom birdsnest on you, when they do, you can't clear them underwater.

 

[String]

I really dislike enclosed reels - they dont prevent line running off and can jam without being seen (and are hard to fix).

 

[peterbj7]

As is all things, there are good and bad designs of enclosed and semi-enclosed reels. The particular model I use for DSMB deployment (only) is AP Valves' Buddy Reel, and I have only ever had one problem with it in (literally) thousands of deployments, and that problem (a minor design fault) was easily dealt with at home with a hexkey wrench and a tiny blob of marine putty.

I believe there is no significant likelihood of the reel jamming or the line coming off its spool, and indeed the second has never happened. The reel is very compact and easy to handle single-handed when deploying, and the locking mechanism is both extremely durable and dependable, and very positive in action.

Don't condemn "complexity" in reels until you've tried this one.

 

[String]

Amusing in that in the UK that buddy pocket reel is known informally as "the buddy reel of death" and widely recognised as the worst product AP valves have ever made.

Personally i use a bit yellow McMahon ratchet reel. Its bulky but its solid and has so far worked 100% of times. I do sometimes use a spool for those very rare dives where i deploy a bag shallow but thats maybe once a year.

 

[peterbj7]

I've often used a buddy reel in the UK and have never heard that comment. Can you tell more?

I have a McMahon ratcheting reel and in fact used one (a guest's) yesterday. IMO it is inferior to the buddy reel in several ways, and the guest has also come to that view.