Minor Rant about DIN 1st Stage Dust Cap

[certainmisuse]

Regarding my new ScubaPro MK17 DIN with attached "dust cap": it has no threads?? How the hell does that prevent water entry? At least for a yoke valve you can squeeze the cap in down. Then the manual says rinse with the cap on but no mention of Yoke versus DIN, big difference in my mind. I know that dust caps have been discussed much before. What do folks use for DIN regulators if you want to submerge the regs? Something like this?

I understand that washing everything down while pressurized would get around this, but lets stick with the submerge option for this discussion.

Thanks.

--
David

 

[davehicks]

So don't submerge it. Spay it off if you can't submerge it presurized. Even with threads if the o-ring is not compressed it won't be water tight.

 

[certainmisuse]

So don't submerge it. Spay it off if you can't submerge it presurized. Even with threads if the o-ring is not compressed it won't be water tight.

I see. Was curious if someone had invented something that would hold the seal, was small, and frankly much lighter than a tank.

 

[Divectionist]

They invented it in the form of a female Delrin screw-in cap that has a surface to seal with the O ring. You can screw it in very tight and it will absolutely be a good enough seal to rinse your 1st stage without worry.

 

[JackD342]

This one does say it has an o-ring seal in the description.
Aluminum Regulator Din Cap – Innovative Scuba Concepts

 

[doctormike]

I might be wrong about this - I'm not an equipment tech or anything - but I always thought that if you are going to actually soak your regs you were supposed to keep them pressurized to prevent water from getting upstream where it won't dry out. It's not just a question of getting a tight enough seal on the fist stage, I think that an unpressurized second stage can let water get up into the hose if you accidentally hit the purge button or move some of the flow controls.

And if you aren't going to pressurize your regs, then you should just rinse them under running water, which is what I do.

I think that's why it's called a "dust cap". It's to keep dust and dirt out of the first stage during transportation and storage. It's not meant to keep water out when the first stage is submerged for any length of time.

 

[Centrals]

"Dust Cap"
Why would anyone expect it to be water proof?

 

[JackD342]

I might be wrong about this - I'm not an equipment tech or anything - but I always thought that if you are going to actually soak your regs you were supposed to keep them pressurized to prevent water from getting upstream where it won't dry out. It's not just a question of getting a tight enough seal on the fist stage, I think that an unpressurized second stage can let water get up into the hose if you accidentally hit the purge button or move some of the flow controls.

And if you aren't going to pressurize your regs, then you should just rinse them under running water, which is what I do.

I think that's why it's called a "dust cap". It's to keep dust and dirt out of the first stage during transportation and storage. It's not meant to keep water out when the first stage is submerged for any length of time.

Very few divers that own their own regulator also own a cylinder, much less a tub large enough to,place one in. But failure to soak the salt out of a regulator after a vacation trip absolutely can result in premature deterioration of gear, or add a bit of a challenge to the next service.
Yes, you want to be sure to not press the purge while soaking unpressurized. There are also some brands with a “seat saver” feature that require a different protocol. Keeping the 1st stage higher than the 2nd stages is good advice either way.
Most yoke dust caps really are intended to make a water tight seal for soaking and rinsing. My DIN set gets soaked with the yoke adapter and dust cap in place.

 

[JohnnyC]

One of the benefits of using a drysuit inflation bottle is the ability to attach it to your first stage and throw it in the tank.

I realize not everyone can do this, but if you have the ability, it’s worthwhile.

 

[fmerkel]

Been soaking DIN regs with only the 'dust' cap for over 20 years. No problem.

Interesting people think you can screw a DIN reg into a tank and seal it against 3500psi-no problem, but get very concerned about screwing a dust cover onto that same DIN and putting it in a tub of water with trivial pressure differential.
Unless it's not made well they are designed to seal.