What makes a Conshelf 30 different?

[Green Frog]

Thanks, that’s a good point, @Zef. I had used adaptors a fair amount on the 3/8” HP ports on early AL 1st stages without thought, but now I’ll be extra cautious with all of these steel adaptors in brass outlet ports. For that matter though, the blanking plugs used to block off any unused ports deserve a little extra care as well.

I don’t know whether I mentioned this but the port size question came up not for the Royal or Pro or whatever 1st stage that looks like a UFO, but one of the last of the Conshelf Series, an SE3. My plan was to get another first like my C 22 so I would have 2 alike for backup and/or sharing. I like having 4 LP ports so I can configure my hoses to suit. That does leave at least one LP port with a blanking plug though.


The question still on the table is whether the “innards” of the C 30 second are just regular 1085 parts or whether it gets a special HP seat and volcano? It appears that I’m beginning to acquire a supply of 1085 seconds, and my main goal is interchangeability. Along with that, does the SE3 first stage take the same service parts as the rest of the Conshelf type firsts? I want to have the simplest parts inventory possible, for obvious reasons, and this seems like a good place to start.

For the purists in our midst (and I kinda started out as one myself) I guess I should apologize, but I find myself following a different path now. I want the best of the classic parts and will mix and match within the Conshelf era (of the 1085 first stage era) and related variants. I hope to go classic while maximizing utility. I guess I should go to confession and say a few mea culpas, but I’m a Baptist so I guess I have to ask absolution here!

Froggie

 

[Zef]

Thanks, that’s a good point, @Zef. I had used adaptors a fair amount on the 3/8” HP ports on early AL 1st stages without thought, but now I’ll be extra cautious with all of these steel adaptors in brass outlet ports. For that matter though, the blanking plugs used to block off any unused ports deserve a little extra care as well.

I don’t know whether I mentioned this but the port size question came up not for the Royal or Pro or whatever 1st stage that looks like a UFO, but one of the last of the Conshelf Series, an SE3. My plan was to get another first like my C 22 so I would have 2 alike for backup and/or sharing. I like having 4 LP ports so I can configure my hoses to suit. That does leave at least one LP port with a blanking plug though.


The question still on the table is whether the “innards” of the C 30 second are just regular 1085 parts or whether it gets a special HP seat and volcano? It appears that I’m beginning to acquire a supply of 1085 seconds, and my main goal is interchangeability. Along with that, does the SE3 first stage take the same service parts as the rest of the Conshelf type firsts? I want to have the simplest parts inventory possible, for obvious reasons, and this seems like a good place to start.

For the purists in our midst (and I kinda started out as one myself) I guess I should apologize, but I find myself following a different path now. I want the best of the classic parts and will mix and match within the Conshelf era (of the 1085 first stage era) and related variants. I hope to go classic while maximizing utility. I guess I should go to confession and say a few mea culpas, but I’m a Baptist so I guess I have to ask absolution here!

Froggie

As already discussed, the Conshelf 30 2nd stage is just a rebadged XIV with a black powder coated faceplate ("box top").

Internally the Conshelf 30 and the Conshelf XIV (1085 series bodies) are identical. They are also internally identical to the Conshelf 21, Conshelf SE2, Conshelf SEA, Pro DIver, and Octopus that have the 1074 series body in common.

The original part numbers for the service kits are 900007 for the 30/XIV and 900006 for the others, but comparing the part numbers for the parts listed that are included in each kit, there does not seem to be any difference.

Compare for yourself:

-Z

 

[Green Frog]

@Zef, I’d like to pick one more nit, if I might. It appears that each Conshelf second intended to serve as an octopus should have a poppet spring#108514. Does this poppet spring increase cracking pressure to prevent free flow when the octo second is stowed out of use?

If I go on that assumption, and if I service a 1085 box that I intend to devote to service as an octo, it would behoove me to replace the 108504 spring with a 108514, correct? Attacking from another angle, how much actual difference would it make if I just used a random freshly serviced “standard” 1085 box?

Thanks for all of your help for your past input as well as that which may come as yet,

Your AmPhibious Phriend

 

[Zef]

@Zef, I’d like to pick one more nit, if I might. It appears that each Conshelf second intended to serve as an octopus should have a poppet spring#108514. Does this poppet spring increase cracking pressure to prevent free flow when the octo second is stowed out of use?

If I go on that assumption, and if I service a 1085 box that I intend to devote to service as an octo, it would behoove me to replace the 108504 spring with a 108514, correct? Attacking from another angle, how much actual difference would it make if I just used a random freshly serviced “standard” 1085 box?

Thanks for all of your help for your past input as well as that which may come as yet,

Your AmPhibious Phriend

Since the 1085 series and 1074 series did/does not have an adjustable orifice, the cracking pressure is determined by the lever height and the poppet spring. The spring spec'ed for the 30/XIV "octo" (part # 108514) should be slightly stronger than the standard spring (part# 108504).

There is nothing wrong with using the standard spring in both the primary and backup (octo) 2nd stages.
With other model 2nd stages that have an adjustable orifice to tune the regulator, some recommend to tune the backup the same as the primary...the major difference is that with an adjustable orifice one can detune if they find they regularly experience freeflow. With the 1085 you would ideally need the stronger poppet spring to detune....one can also play with the demand lever height but that is not really recommended as it can affect whether the demand valve completely opens or not.

How much difference does it make would be determined by how you configure your reg set (octo on necklace or otherwise attached) and whether you dive in current + how strong the current is.

If you have 2 standard 1085s then dive them and see how things go. If you don't experience freeflow then all is good, if you do then you can work on sourcing the octo version of the spring (part # 108514):

Buy 1085-14 Aircraft Part of U S Divers Co Aqua Lung Div | AOG Parts in Stock

Buy 1085-14 aircraft part of U S Divers Co Aqua Lung Div at ASAP AOG. We have an inventory of U S Divers Co Aqua Lung Div including 1085-14 AOG parts.

www.asapaog.com

https://www.amronintl.com/spring-octopus-conshelf-xiv.html

BTW, there is an adjustment screw for the purge button under the decal...the service manual for the XIV states that propper cracking effort is at 1-inch of water column with an IP of 140 psi (+/- 5 psi). The purge button adjustment screw can be turned in (clockwise) in an effort to help eliminate hissing/freeflow.

-Z

 

[GJC]

You can actually feel the difference between the 2 springs with your fingers gently compressing the springs.

There are 2 unconventional ways to adjust the cracking effort for 1085 second stages.

1 -Increasing or decreasing the IP of the first stage.

2 -Using extreme care, gently manually stretch or compress the second stage spring. CAUTION Too much will ruin the spring. You will probably ruin a few springs before becoming skilled enough to do it correctly.

 

[DIVER1969DOWN]

Mention of the Conshelf 30 shows up from time to time, but in spite of several serious searches here and via Google, I can’t find a definitive answer. What was it really? It appears that AL found a batch of unused Con XIV seconds and just made a new purge button sticker and hung them on some general C 22 or 23 firsts and sent them out. Those I have seen don’t have the external poppet adjust of the Conshelf 14. Can anyone solve this problem for me?
TIA ~ ~ Froggie

like all usd 1st stage the number was for the first stage not the second stg. the 30 was original known as the prodiver the difference being the original pro diver had a 2nd stg known as a Royal which did not use the stf 2nd stg parts put a unique wire loop lever system. the 1/2" hose was not the unique part put the firsst stg deviated from the 90 degree bend of airflow hp to lp to a i believed to be 60 degrees to improved air flow in a diaphragm 1st stage as usual usd great idea to soon and no development after introduction to work out the bugs, the so call black cover 2nd stg still used the same parts as all the metal 2nd stgs since the 60's