New BP/W checkout dive

[bobmaggi]

First off I want to thank everyone for the great advice I got on putting together a BP/W, whether you know you helped me or not, I used a lot of threads to pick out the plate, harness and wing from various manufacturers. I got it all together and just back from using it on 2 dives at the Portage, OH quarry.

I have some questions based on my initial experiences.

I got the Oxy-Chek 45# wing, it seemed pretty balanced but then again so was my jacket. It did seem a bit easier to maintain horizontal trim. On the surface I found it difficult to gauge how much air I put into it, I guess I was used to the jacket squeeze to let me know when I had enough! But I did find that I put me up out of the water easily and I didn't notice any tendency to want to tip me forward either.
I noticed that the bottom dump valve on the wing is mounted on the opposite side of the wing as the inflator (facing the diver). Now this doesn't seem to make sense to me, shouldn't it be on the top? It seems a bit useless unless I'm standing on my head and need to dump air? At least that was the only way I seemed to be able to get it to work. I hope someone can give me the reasoning behind that design so I can use it properly.
I adjusted the harness so that I can easily place a closed fist between the strap and my chest but I noticed that the left strap seemed to want to wander off my shoulder and I would have to pull it back on. I assume that this is an indication that it should be tightened up some or is this normal? The right strap (same lenght as the left) did not seem to exibit this.
What is the right way to place the weight belt? I put it on first and then buckled the harness and the crotch strap over it. But this seems that it would make it more difficult to ditch in an emergency.
Lastly I found that I was hitting the top of the tank looking up. On the second dive I moved the tank down so that the top strap was half over the top curve of the tank. I can also move the STA down one adjustment (about 1/2- 3/4 inch). But I'm not sure that this would be enough to keep the bruises off the back of my head. Are there any other options or should I drill additional holes?
Hopefully I can incorporate your suggestions in time for next Saturdays dive!

Bob S.

 

[RiverRat]

Hey let me know how you make out with that new wing! I'm going to mount up an Oxychek 45# to my FredT plate. I just got the plate and will be filing and sanding it while waiting for the wing and backordered Scubapro tank straps. I ordered Fred's two piece STA's so I'm sure I'll be moving them around so I don't bash my head as well. Maybe we can swap info as we tune our rigs. I too will be trying to figure out how to best position the weight belt. I'm guessing it should go over the BP webbing so it's ditchable?

Best of luck...............

 

[IzzyTahil]

bob - many divers wear their weight belts then put on the harness. They do this in case the belt comes lose (the crotch strap will catch it) at depth so they dont shoot to the surface in an uncontrolled ascent.

 

[ChrisM]

I noticed that the bottom dump valve on the wing is mounted on the opposite side of the wing as the inflator (facing the diver). Now this doesn't seem to make sense to me, shouldn't it be on the top? It seems a bit useless unless I'm standing on my head and need to dump air? At least that was the only way I seemed to be able to get it to work. I hope someone can give me the reasoning behind that design so I can use it properly.

With proper weighting, the wing should be near fully deflated when diving. When you are horizontal, the edges of the wing should wrap up around your tank. You can reach back there and feel it next dive. When the wing does this, the rear dump is now on "your'" side. If it was on the back, it would be on the "tank" side.

I adjusted the harness so that I can easily place a closed fist between the strap and my chest but I noticed that the left strap seemed to want to wander off my shoulder and I would have to pull it back on. I assume that this is an indication that it should be tightened up some or is this normal? The right strap (same lenght as the left) did not seem to exibit this.

Yes, tighten the left side a bit. It should not float away

What is the right way to place the weight belt? I put it on first and then buckled the harness and the crotch strap over it. But this seems that it would make it more difficult to ditch in an emergency.

I believe the "common wisdom" is if diving wet, it goes over the harness. If diving drym you can put it under. Altho I have friends (who wear little weight on the belt) that dive wet/under. If it is under, it will be nearly impossible to release and clear during an emergency, IMO.

Chris

 

[ZoCrowes255]

bobmaggi once bubbled...

I noticed that the bottom dump valve on the wing is mounted on the opposite side of the wing as the inflator (facing the diver). Now this doesn't seem to make sense to me, shouldn't it be on the top? It seems a bit useless unless I'm standing on my head and need to dump air? At least that was the only way I seemed to be able to get it to work. I hope someone can give me the reasoning behind that design so I can use it properly.

If you ever get a chance to see a wing you will notice that it will fold up against the tank. If the rear dump valve were on the same side of the wing as the inflator dump you will not be able to reach it while horizontal. If it's on the bottom then you can reach it.

 

[lairdb]

ZoCrowes255 once bubbled...


If you ever get a chance to see a wing you will notice that it will fold up against the tank. If the rear dump valve were on the same side of the wing as the inflator dump you will not be able to reach it while horizontal. If it's on the bottom then you can reach it.

I'm sure there's a thousand similar photos on the web somewhere, but I knew I had this one from a recent trip. You can see that the wing has folded up each side of the tank ("taco-ed") -- it doesn't stay flat against you. This puts the rear dump valve in position for an easy left hand reach.

--Laird

(You can also see that I'm not diving the long hose despite the bp&w, and that I'm slightly overweighted (evidenced by a little more air in the wing than there should be. Steel tank, steel BP, 3mm shorty.) No doubt someone will point these things out if I don't.)

 

[crab]

I always raise and eyebrow when I read about people seemingly calibrating their percieved neutral buoyancy by how little air they have in their wing during a dive. I did a couple of calculations and found that with my LP steel tank, I would be utilizing ~17.2% of the lift on a 45# bladder with a full tank at the start of the dive, and ~21.5% of the lift capacity of a 36# (the one I actually use) bladder. These lift amounts being necessary, of course, for the weight of air I will consume during the course of the dive. Is it just me, or do these ratios of the bladder capacity, which will be required to neutralize my full tank seem to consitute more than just a "minimal" amount of air added to the bladder? I realize that this amount should taper off to as close to 0% of capacity as possible by the end of the dive, but at the start of the dive it seems like a relatively significant amount of air in the bladder.

Thoughts, please.

 

[pdoege]

That sounds about right.

I have a similar amount of air in my wing at the beginning of the dive and my wing is pretty much empty at the end of the dive.

This is on my pioneer 27, I haven't had time to rig the OxyCheq yet.

Peter

 

[divegeek]

I also did a my first checkout dive with a BP/Wing this weekend. My STA came loose twice. Do I need to replace the washers with lock nuts?

 

[jplacson]

Your STA came loose?!?!? :O

Man, that's freaky!!! Losing your STA is worse than having your tank slide out from the tank strap (if it slides out, your hoses still snag on the tank strap... holding it against your body)

Whew... one more thing that makes me glad I got my Pioneer over the new Eclipse.