assembling equip. question

[d56nut]

Hi All,

I'm getting ready to purchase my first reg and octo and guages. I'm considering purchasing them from different places. Is this a problem? Does the equipment have to be assembled by a shop or is this something I can do myself?

Thanks!

 

[SDAnderson]

This isn't something I'd encourage people to do unless they have a good working knowledge of regulators. Assembling the pieces isn't all that hard to do, so long as you're at least a little bit "handy" but there is more to the process than screwing the bits together.

Remember, this is life support equipment and not the place to try to shave a few dollars off your bill. I wouldn't dive with a new regulator until it has been opened up and inspected and tested, you probably don't have the equipment for that, even if you learned how. Mixing and matching first and second stages from different manufacturers can be tricky, unless you're willing to learn enough to avoid problems with little things like variations in recommended second stage IP settings, yadda, yadda...

Obviously, I don't know exactly what you have in mind or why, but be careful.

 

[scubatoys]

I kinda' agree with reefraff - It is easy, and in all honesty, most manufacturers run the same IP unless you get something really bizarre... But it is still a good idea to test out the whole unit after the parts are assembled. We always hit each set with a IP test, and crack pressure check before we send one out.

The other thing you may want to consider, is if you have to get 2 or 3 parts from 2 or 3 places... what about service? Let's suppose you have a little free flow on an octo... do you send the octo back to the place you got the octo?? Many times, it's the IP creeping from the first stage... so send the octo back to one place, and the 1st stage to another... You can see it could be a logistical nightmare if you had any problems with the gear. I'd really suggest you find one place that has all the stuff you need... even if it is differnet brands... I'd still try to find the "one stop shopping".

 

[DA Aquamaster]

For the sake of simplicity I would buy it all in one place to ensure it can all be serviced in one place. Most manufacturers have first stagess that operate in the same IP range of 120 to 145, but 25 psi can make a big difference in how the second stage performs.

Ideally a tech at the shop should tune the octo to the specific first stage to ensure it functions as designed. The tech can also take into account factors such as IP change with tank pressure if the first stage is unbalanced and can tune the octo to have the breathing traits you want. Care also needs to be taken when adjusting "dual adjustment" second stages that the lever height is correct once the orifice and spring pressure is properly adjusted to ensure the octo will deliver its maximum amount of air. I have had some octos come across my bench where the lever was so low that they would deliver virtually no air and that is a situation that will just serve to magnify the problems in an OOA situation and potentially lead to two fatalities.

Many companies set the cracking efforts fairly high on their octos (as much a 1.0 inches of water more than a regular second stage of the same model) to 1) prevent unintentional air loss and 2) make it easier to get by with just screwing it on to a first stage with no adjustment.

If the octo has an adjustment knob, a flow vane, or a purge cover that fully protects the diaphragm from contact or current, number 1 is not an issue and, as indicated above, number 2 is not the way it should be done. The end result of a high cracking effort is just a hard breathing reg, and that is not always ideal in a situation where you actually have to use it. I like to set up octos with cracking efforts that are .2 to .4 inches of water higher than the specs for a second stage of the same model. You avoid over an overly sensitive octo yet still maintain a decent breathing reg.