DSMB & spool purchase - my considerations.

[ljpm]

While on the topic of SMBs and spools, are there any spools with larger holes? I still have difficulty deploying. While watching youtube videos I have noticed that divers usually put their finger through the hole. My finger barely fits without gloves, and by barely I mean they get stuck if any more than the last digit goes all the way through. (I wear XXXL gloves, only because that's the largest I can find. They are actually tight.) With 5 mm gloves my finger doesn't fit at all.

 

[doctormike]

While on the topic of SMBs and spools, are there any spools with larger holes? I still have difficulty deploying. While watching youtube videos I have noticed that divers usually put their finger through the hole. My finger barely fits without gloves, and by barely I mean they get stuck if any more than the last digit goes all the way through. (I wear XXXL gloves, only because that's the largest I can find. They are actually tight.) With 5 mm gloves my finger doesn't fit at all.

Do NOT do that. Good way to break a finger. You pinch it with two fingers to hold it securely enough so you don’t drop it but loose enough so it can turn and so you can release it if it sticks (less likely that with a reel, but possible if it’s wound incorrectly)

 

[ljpm]

Do NOT do that. Good way to break a finger. You pinch it with two fingers to hold it securely enough so you don’t drop it but loose enough so it can turn and so you can release it if it sticks (less likely that with a reel, but possible if it’s wound incorrectly)

Thanks. That was the way I was doing it. It is really amazing how many youtube videos have people putting fingers through the hole.

 

[doctormike]

Thanks. That was the way I was doing it. It is really amazing how many youtube videos have people putting fingers through the hole.

Normalization of deviance!

 

[divinh]

As a vacation diver, I didn't encounter a situation where I was required to have an SMB until dive #84, in Maui. Previous dives were from Koh Tao, Ishigaki, Okinawa and Koh Lanta. The requirement in Maui was due to some drift dives, which existed in mild form at the previous locales, but I guess weren't as great a concern? For me, the difference was in surface currents, which were quite strong in Maui. Rangiroa and Fakarava in French Polynesia had very strong underwater currents but required no SMB's, probably due to drift diving into the lagoon? Whereas in Maui, the end point was the open ocean?

The minimum required SMB for Maui was just a vinyl one, sold at the shop for about $8-10. It's only meant to be deployed at the surface. No spool needed, nor were there any attachment points for a line. Prior to buying this one, I had no idea that there existed anything different than the ones I've seen DM's and Instructors deploy.

In the last few weeks, I've been prepping for a liveaboard for Komodo in late June. My preference is to keep things at a minimum, so was only considering a 3'-4' DSMB and spool. After reading here and watching some YouTube videos (one in which someone drifted 25km in 5 hrs in Komodo!), I opted for a 6' DSMB with radar reflective tape. If this DSMB turns out to be too big, I might opt to add a smaller one for other dive trips.

I actually found the process of selecting a DSMB and spool quite daunting, as there were so many options in size, inflation method, with or without purge valve, line length and spool sizes. I think I made a good choice for Komodo, but it might not be a good general solution for most of my vacation diving.

 

[doctormike]

I think that two things are getting confused.

Anyone diving in the ocean should have at least one way of signaling the boat in case of separation, and of marking the divers position on the surface if a search is necessary. The most common device for this is a large tube, inflated on the surface. This could be a DSMB (with an inflator valve, a dump valve and a line) just being deployed on the surface, or a cheaper and smaller dedicated surface-only device ("safety sausage") like the one that divinh described above.

As far as deploying an SMB from depth, there would be several reasons for doing that.

Drift divers need to mark their position during the entire dive so that a boat can follow them. In this case, the SMB is being used as a dive float.

Another reason is for you to signal the surface when you aren't going to be able to surface right away - i.e. when you have a decompression obligation - and you are moving relative to the boat. That would happen when the boat is anchored and you can't find the anchor line. It is crucial to send an SMB up right away, so that the boat can follow your position as you drift away from them over the time of your deco. Yes, you could also drift over the course of a safety stop, but that's optional and shorter, so less of an issue.

An SMB can also be used as an alternate ascent line if you can't find the anchor line but don't want to drift away from the boat - you can secure the line to the bottom. Always better than a drifting ascent away from the boat, if you have time and gas to do that. Many dive boats will see an unplanned SMB deployment as a sign of an emergency, so they will often send a crew member down to check on that diver.

If you are going to be deploying an SMB from depth, you should have enough line so that you don't have to wait until you are in mid-water at your safety stop to deploy it. You should also practice that skill frequently - it's not trivial.

 

[Centrals]

While on the topic of SMBs and spools, are there any spools with larger holes? I still have difficulty deploying. While watching youtube videos I have noticed that divers usually put their finger through the hole. My finger barely fits without gloves, and by barely I mean they get stuck if any more than the last digit goes all the way through. (I wear XXXL gloves, only because that's the largest I can find. They are actually tight.) With 5 mm gloves my finger doesn't fit at all.

They are available eg. Light Monkey
Light Monkey Delrin Spools with S/S Snap

 

[Jay]

FWIW I bought the AP Reel in the OP. It can be modified so it’s click on/off (no need to hold the release button) and it’s 40m.

 

[Dave Bevan]

I think that two things are getting confused.

Anyone diving in the ocean should have at least one way of signaling the boat in case of separation, and of marking the divers position on the surface if a search is necessary. The most common device for this is a large tube, inflated on the surface. This could be a DSMB (with an inflator valve, a dump valve and a line) just being deployed on the surface, or a cheaper and smaller dedicated surface-only device ("safety sausage") like the one that divinh described above.

As far as deploying an SMB from depth, there would be several reasons for doing that.

Drift divers need to mark their position during the entire dive so that a boat can follow them. In this case, the SMB is being used as a dive float.

Another reason is for you to signal the surface when you aren't going to be able to surface right away - i.e. when you have a decompression obligation - and you are moving relative to the boat. That would happen when the boat is anchored and you can't find the anchor line. It is crucial to send an SMB up right away, so that the boat can follow your position as you drift away from them over the time of your deco. Yes, you could also drift over the course of a safety stop, but that's optional and shorter, so less of an issue.

An SMB can also be used as an alternate ascent line if you can't find the anchor line but don't want to drift away from the boat - you can secure the line to the bottom. Always better than a drifting ascent away from the boat, if you have time and gas to do that. Many dive boats will see an unplanned SMB deployment as a sign of an emergency, so they will often send a crew member down to check on that diver.

If you are going to be deploying an SMB from depth, you should have enough line so that you don't have to wait until you are in mid-water at your safety stop to deploy it. You should also practice that skill frequently - it's not trivial.

All of the above is good information.

I would add that during deco dives one of the team will carry the big SMB for mid water ascents if you don't make the line. This should have a reel with enough line to be deployed from max depth. This can also be deployed in an emergency such as loss of buoyancy or if a medical problem for example and the team need to get off the deck ASAP (no time to find the ascent line). This is called a Primary Reel.

In addition to this each team member has a small SMB with finger spool to deploy if separated from the team and required to mark position while carrying out deco so you don't get run over by a boat.

If you have protocols set up for safety divers then each diver will carry a yellow DSMB on a double ender. This can be inflated and clipped to the primary reel line or your own deployed DSMB line. A yellow DSMB communicates an emergency. In our DC this would stimulate either a safety diver to decend the line carrying spare gas. Oxygen to be prepared on the surface and the boat to be separated from any anchorage ready to move fast back to shore for an ambulance. In the UK this will probably get you a Coastguard helicopter as well.

Another Food for thought on DSMB's if they are found discarded in the UK it is common for a diver search to be launched as they will assume a diver is lost at sea. Mitigate this by writing your email or phone number on the SMB. That way if anyone finds it they can call you to ensure you are safe and not lost. You also might get your SMB back if you lose it. Maybe.

 

[stretchthepenn]

Do NOT do that. Good way to break a finger. You pinch it with two fingers to hold it securely enough so you don’t drop it but loose enough so it can turn and so you can release it if it sticks (less likely that with a reel, but possible if it’s wound incorrectly)

Agreed, on all accounts. I, too, have big hands, and the tip of my middle finger got caught whilst doing a two-finger pinch. It hurt. A lot.