scubapro 380
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It's a good safe second, I wouldn't use it for a primary and which 1st stage are you using it with?
snuggle:
Its an R190 (unbalanced downstream second) with a smaller case.
Not a bad second, but its not as smooth as a balanced. If tuned PROPERLY (and note that most techs DO NOT tune them right) it can breathe VERY WELL, but it will never be as smooth as a balanced. You can get awfully close though.
It makes a good deco second; I use one for that purpose.
You ABSOLUTELY want this reg paired with a balanced first, and it MUST be tuned with that first by the person who services it to get good performance, as it is sensitive to the IP. An unbalanced first will have the IP drift with tank pressure and you won't like how it breathes at all.
The R380 is a dual adjustment down stream poppet valve second stage that basically traces it's mechanical valve assembly roots back to the original Scubapro High performance second stage, but also incorporates an adjustable flow vane. The R190 uses the same poppet assembly but in a smaller case with a smaller diaphragm. This keeps the size down but at the expense of less diaphragm area.
You can set up an R380 (or and R190) to breathe very well with a cracking effort around 1.0 to 1.2 but as Genesis pointed out, it needs to be tuned properly and adjusted while attached to your specific first stage.
A balanced first stage will have a more stable IP and maintain minimum cracking effort regardless of tank pressure. If you have it on an unbalanced first stage (a Mk 2) it will need to be adjusted for minimum effort at maximum tank pressure (normally 3000 psi). If it is fine tuned at a lower tank pressure, it will freeflow slightly on a full tank due to the slightly higher IP at 3000 psi. An IP range of 10 to 15 psi between 3000 psi to 500psi is not uncommon for an unbalanced first stage.
In the old days when I dove with a J valve rather than an SPG, this was actually a bit of an asset as the increased cracking effort toward the end of the dive was an indicator that your air was getting low.
Getting max performance from a non adjustable second stage also takes a bit of time as it should ideally be readjusted about a week after it is re-assembled after an overhaul or alternatively after being left pressurized on a tank for 8-12 hours to allow a seating groove to form in the second stage seat. On a new reg, it's been setting a while anyway so it can just be fine tuned.
This can be problematic however as there is often a substantial difference between the Scubapro specs and the minimum stable cracking effort the reg is capable of achieving. For example the specs may specify a cracking effort of 1.4 to 1.9 inches of water on a second stage capable of stable performance at 1.0 or 1.2 inches. The higher cracking effort makes it more freeflow resitant and keeps the EN folks happy but results in harder breathing regs for the rest of the world. So if you want it set up a certain way, you'll need to discuss it with the tech.
On the bench cracking efforts below 1.2 to 1.0 are posisble but normally result in a slight freeflow when in the water in a normal swimming position. An adjustable second stage lets you correct for this problem by tightening the adjustment knob a bit, so it is easier to tune an adjustable second for minimum cracking effort because if you get it a little too light, it can be corrected by the diver in the water. If you get it too light with a non-adjustable reg, you get a reg with slight freeflow in a normal swimming postion and a crabby diver. This of course is another reason that techs normally err on the hard breathing side of things with a non-adjustable reg.
You can set up an R380 (or and R190) to breathe very well with a cracking effort around 1.0 to 1.2 but as Genesis pointed out, it needs to be tuned properly and adjusted while attached to your specific first stage.
A balanced first stage will have a more stable IP and maintain minimum cracking effort regardless of tank pressure. If you have it on an unbalanced first stage (a Mk 2) it will need to be adjusted for minimum effort at maximum tank pressure (normally 3000 psi). If it is fine tuned at a lower tank pressure, it will freeflow slightly on a full tank due to the slightly higher IP at 3000 psi. An IP range of 10 to 15 psi between 3000 psi to 500psi is not uncommon for an unbalanced first stage.
In the old days when I dove with a J valve rather than an SPG, this was actually a bit of an asset as the increased cracking effort toward the end of the dive was an indicator that your air was getting low.
Getting max performance from a non adjustable second stage also takes a bit of time as it should ideally be readjusted about a week after it is re-assembled after an overhaul or alternatively after being left pressurized on a tank for 8-12 hours to allow a seating groove to form in the second stage seat. On a new reg, it's been setting a while anyway so it can just be fine tuned.
This can be problematic however as there is often a substantial difference between the Scubapro specs and the minimum stable cracking effort the reg is capable of achieving. For example the specs may specify a cracking effort of 1.4 to 1.9 inches of water on a second stage capable of stable performance at 1.0 or 1.2 inches. The higher cracking effort makes it more freeflow resitant and keeps the EN folks happy but results in harder breathing regs for the rest of the world. So if you want it set up a certain way, you'll need to discuss it with the tech.
On the bench cracking efforts below 1.2 to 1.0 are posisble but normally result in a slight freeflow when in the water in a normal swimming position. An adjustable second stage lets you correct for this problem by tightening the adjustment knob a bit, so it is easier to tune an adjustable second for minimum cracking effort because if you get it a little too light, it can be corrected by the diver in the water. If you get it too light with a non-adjustable reg, you get a reg with slight freeflow in a normal swimming postion and a crabby diver. This of course is another reason that techs normally err on the hard breathing side of things with a non-adjustable reg.
ElectricZombie
Contributor
I use one as my backup sometimes. It is a nice reg that breathes great for an unbalanced design. I have no complaints. Do make sure you follow the above advice regarding setting the reg up.snuggle:
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