Maybe plastic isnt a good material for BC construction

[Chavodel8en]

So Ive had my back inflate BC for ~15 years. I bought it super-cheap on closeout, it dived fine, never saw the need to replace through hundreds of dives, local and travel. I especially like that it had 2 tanks straps.

So yesterday, after months of no diving due to COVID, I went shore diving.

Pretty strong waves getting in and out (although pretty flat in the dive), those waves carried alot of force. Enough force, apparently to completely snap the tank strap assembly off the BC. The tank strap didnt break -- the entire tank strap assembly snapped off completely from the plastic backplate material of the BC.

First a wave must have snapped the top strap assembly, as I felt the tank flopping sideways, then another must have broke the bottom one too, and the only thing holding the tank was the tank locator strap.

Luckily, it happened after the dive, close to exiting. It would have been "fun times" if it happened during the dive and my steel tank suddenly started sinking, while I started ascending. I guess I would have gotten a crash course in monkey diving.

So looks like I will finally buy a BP/W -- with metal, not plastic, connecting the tank to me.

 

[rhwestfall]

oops

 

[Vicko]

And a cheap plastic bc lasted only 15 years?
Shocking.

 

[Rusty Shackleford]

There are many different grades of polymer. Some age poorly, others hardly at all.

Good ones have UV inhibitors.

 

[The Chairman]

Fit and comfort. After fifteen years, I think it's done its job.

 

[Graeme Fraser]

There are many different grades of polymer. Some age poorly, others hardly at all.

Good ones have UV inhibitors.

At last, a good reason for living somewhere sunshine is a rare commodity!

 

[Chavodel8en]

I don't particularly feel cheated that my $200 BC failed after 15 years of loyal service. I actually feel a little nostalgic replacing it. But that failure was pretty significant. "Keeping the tank attached to you" is a pretty important role a BC plays that I didn't really think about much before yesterday.

Interestingly, about a year ago, the plastic cam-band in the top tank strap of this BC also snapped and I didnt notice until after a dive (the tank placement felt a little funny walking in, didn't notice anything during dive -- it probably broke when I flipped the cam). I replaced the tank strap and kept the BC. But maybe it was warning me -- the plastic in this BC is good for about 15 years only.

So a more accurate title would have been "Cheap plastic may not be a good long-term choice for BC construction"

I would be confident in, for example, high quality plastic backplates.

 

[kelemvor]

I would be confident in, for example, high quality plastic backplates.

At least you might be able to see signs of cracking before catastrophic failure. Maybe.

I've got a plastic dive-rite plate. I don't really use it, although I did dive it about 6 times just to check it out. Weighs about the same as my aluminum plate, which is a lot thinner. Neither seem to have any problems with my worthington lp108s.

 

[Landau]

with metal, not plastic, connecting the tank to me

Hmm... every BP/W I've seen has plastic (usually nylon) straps connecting it to the diver.

 

[halocline]

Hmm... every BP/W I've seen has plastic (usually nylon) straps connecting it to the diver.

With metal buckles. I guess they could make the straps out of chain link.