New Second Stage on Existing Octopus?

[nath1772]

Hi GuysI currently have an ageing set of Aqua Lung Regs, they're fine but i would like an upgrade...is it possible to just get a new second stage, then fit to my exisiting first stage and octopus etc? This way i can get a brand new second stage at a lower cost.i would assume i can buy a new reg hose and second stage and job done?would it be as simple a task as it would be to renew the hoses on an exisiting kit, or could there potentially be compatability issues?any help appreciated.Thanks in Advance,Nathan

[herman]

Welcome to the board Nathan.
The quick answer is it will work fine but like always there is more to the story.
As long are your first stage is working properly, there is no real performance gain to be had by replacing it but depending on your second stage design, upgrading it may be a step up. With the exception of a rare few regs, pretty much all reg use an intermediate pressure (IP) of 135-145 PSI so your choice of second stages is broad, as long as the second stage is rated for an IP in that range, any second stage will work. All Aqualung regs (except some very old US Diver ones) are rated for 135-145 psi. The issues come in service and initial installation. At least here in the US, most shops carry a few brands and will only service those. If you choose a different brand of reg for your second stage and your preferred service shop does not service both, you can have problems getting the complete reg serviced. The next issue is for best performance, the second stage needs to be tuned or adjusted to work best with the first stage. Since both the first and second stage have an acceptable range of working pressures, if the first stage happened to be adjusted to one end of the range while the second stage is adjusted at the other, you will not get the best performance out of them or possibly the second stage will free flow. This is not a compatibility issue, just one of tuning them to work together. If your other stages are due for service, this is not an issue (assuming your shops works on both brands) because adjusting the stages to work together is part of the service. If it not up for service and you buy from a local shop, I would think they would be willing to adjust it for you.....or you can learn to do it yourself but that is a little more involved.

[nath1772]

Thanks for the reply

I'll probably stick with Aqua Lung in order to keep everything the same. My first stage is fine and balanced, so assuming I get a good balanced Aqua Lung second and a set up i'll be good to go...?

With regards to tuning myself, i'd rather learn than pay others to do technical work - any idea where to start to learn the ins and outs? I'm pretty good with things like this and well tool'd up.

PS - in the UK most dive shops carry a variety of brands and will service anyhting from my experience

thanks
Nath

[Zung]

Get the Harlow book, go through it and give us the details of what you have, or post pics, and we'll talk about special tools, if required.

[nath1772]

Okay cool - i'll look at getting the book ordered, my old second stage will make a useful guinea pig I suppose in that case!!

[j2s]

Thanks for the reply

I'll probably stick with Aqua Lung in order to keep everything the same. My first stage is fine and balanced, so assuming I get a good balanced Aqua Lung second and a set up i'll be good to go...?

With regards to tuning myself, i'd rather learn than pay others to do technical work - any idea where to start to learn the ins and outs? I'm pretty good with things like this and well tool'd up.

PS - in the UK most dive shops carry a variety of brands and will service anyhting from my experience

thanks
Nath

Go to frogkick.com to download manuals for reg.'s/specs and you'll need some gauges; an IP gauge and a magnehelic + a good torque wrench...With those items you can fine tune your gear or interchange compatible brands......Scubatools.com here in the US carries tools if you can't find 'stuff' in EU.....And I don't think there are trade restrictions.....