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depthdevil
08-06-2016, 05:51 AM
Hi there. What's available for simple decanting or mixing? I have donor twinsets for o2, and air. Shortly will be a j of he. It's the panel that I need, or should I just stick with whips? I'm trying to keep things as simple as poss. Any thoughts or ideas please? Thanks.

MikeF
08-06-2016, 06:35 AM
whip, gauge, and compressor for air top. what more do you need for nitrox? for trimix you really need a booster before a mixing panel.

OutOfTest
08-06-2016, 06:55 AM
Booster or CF...preferably both.

CF for trimix, booster for O2 and 50%. Stick to standard gases and you're onto a winner!

Ian_6301
08-06-2016, 07:43 AM
Cf?

Paulo
08-06-2016, 07:47 AM
Continuous flow.


OP if you have far too much money and have a few grand hanging around with nothing tobdo with it then get a panel. Otherwise a good whip with a good digital guage with a compressor and booster is just as good. You will need a compressor and booster with a panel anyway

Nickpicks
08-06-2016, 08:12 AM
A panel is really just a few valves which do the same job as a whip. They just make it less easy to cock up by following a simple routine: add X bar of He, then Y bay or O2, followed by Z bar of air. You can do exactly the same with a single whip / gauge, but you have to connect it to each source in turn - a panel is all permanently connected and mounted on the wall.

Having said that, some people can still cock it up, usually by ignoring the cascade system and taking the top off the fullest Js - that does annoy the rebreather divers in our club!

ebt
08-06-2016, 08:32 AM
If you want simple, stick with whips. I've seen a lot more mistakes made with panels. When you're spinning whip ends in/out you are spending time having to look directly at cylinders and it seems to give your hungover brain more of a chance to notice a mistake.

Plus if you run one whip for O2 and one for dil etc you've got spares in case something goes wrong ;)

Panels come into their own when you're doing lots of cylinders.

WFO
08-06-2016, 12:02 PM
Just stick with a whip if you're talking the sort of volumes with twinsets full of air (twinset full of o2... fk that, a J is cheap enough)

Far more important to know what you're doing and why before you try start "streamlining" by putting all the valves in front of your face, panels are really a dive shop/expedition thing where you've got 10 twinsets of awkward cunts 3 reblends 4 weird mixes and 4 standards and "oh fck why have I got more mixes listed than I have sets in front of me"

matt
08-06-2016, 12:10 PM
I have J's of O2 and He and have just used whips and a booster.

Matt.

iain/hsm
08-06-2016, 12:16 PM
Hi there. What's available for simple decanting or mixing? I have donor twinsets for o2, and air. Shortly will be a j of he. It's the panel that I need, or should I just stick with whips? I'm trying to keep things as simple as poss. Any thoughts or ideas please? Thanks.
Anything you want is available it’s just the fine details you need addressing and where you what you want to end up with.

A well designed panel will be integrated to safely mix, blend distribute, route analyse and store all your gas. From that you can analyse dispense, fill or blend.
It can do as little or as much as you want and even be designed to intigtrate into a future scope of supply.

In a good design all the individual components you use will be specific, detailed and designed fit for purpose, consideration to gas flow and velocity, adiabatic compression hazzards, particulate contamination, service, spare parts availability, oxygen cleaning and ease of calibration will all be part of the design.

It should be more than a box on the wall, a engraved front panel with gauges valves and dangling lines.

On the other hand you could just simply buy the components and build your own, they are not expensive.

You just need some detailed advise. Iain

depthdevil
08-06-2016, 02:21 PM
Thanks for replies so far. Looks like my first mistake is the twins of o2? Prices are very reasonable for o2 j size. Next phone call to the gas company. Thanks.

Paulo
08-06-2016, 04:55 PM
Thanks for replies so far. Looks like my first mistake is the twins of o2? Prices are very reasonable for o2 j size. Next phone call to the gas company. Thanks.

Keep an eye on rental costs. J rentals are not cheap

drysuitdiver
08-06-2016, 06:19 PM
Keep an eye on rental costs. J rentals are not cheap

Depends if you use the company discount when you call BOC.

Our fab shop has been known to use 3 a week when there has been copper pipe to braze . 54mm and above solder won't do ! And we have some massivly complex modules being built at moment.

The bull nose adaptor was best thing I bought for taking the top end of a new J :)


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WFO
08-06-2016, 08:31 PM
Keep an eye on rental costs. J rentals are not cheap

Something like 7 a month from couple of suppliers I checked with

Need to be careful with BOC, they take the piss, handling fees and stuff

Paulo
08-06-2016, 08:33 PM
7 a month is 84 a year per J. Doesnt be long adding up.

I currently have 4 Js in the shed

WFO
09-06-2016, 09:56 AM
They'd probably charge you that to fill a twinset with O2 in dive shop though!!


Anyone used these cheap gauges for blending?
http://www.ebay.co.uk/itm/250BAR-3600PSI-Digital-Hydraulic-Pressure-Gauge-60mm-NPT1-4-Base-Entry/121761339438?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%2 6asc%3D36498%26meid%3Db1d5cfa6788b4974a56c0da47fc9 6e6d%26pid%3D100005%26rk%3D3%26rkt%3D6%26sd%3D1217 61340767

matt
09-06-2016, 10:21 AM
They'd probably charge you that to fill a twinset with O2 in dive shop though!!


Anyone used these cheap gauges for blending?
http://www.ebay.co.uk/itm/250BAR-3600PSI-Digital-Hydraulic-Pressure-Gauge-60mm-NPT1-4-Base-Entry/121761339438?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%2 6asc%3D36498%26meid%3Db1d5cfa6788b4974a56c0da47fc9 6e6d%26pid%3D100005%26rk%3D3%26rkt%3D6%26sd%3D1217 61340767

No, but it looks OK to me. The one I have was a lot more money and on the back says "not for O2 use". It was from sub-aqua products, bought with an O2 booster pump supplied by gasboosters.

Matt.

Paulo
09-06-2016, 10:44 AM
Not used that guage but for 30 is worth a punt. Add it to a din male and female and a gas block with a bleed screw and it would be very versitile.

I could be wrong but I always assumed a digi guage would be safer with o2 than an analogue one. The only part that would come into contact with the gas is a pressure sensor and not the internals of the guage which could hold all sorts of shite

Dave1w
09-06-2016, 02:16 PM
I guess it would depend if they have any quality control, what if they test it before shipping, and as it for hydraulics, use oil.... Cheap Chinese so probably not tested so you may be ok!


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cathal
09-06-2016, 03:10 PM
I guess it would depend if they have any quality control, Cheap Chinese so probably not tested so you may be ok!
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As the gauge is needed for blending, accuracy is essential. While this gauge is cheap, when you start using it to blend He especially for OC trimix, the gauge inaccuracy could turn into a rather expensive issue with wrong mixes of trimix being produced using large quantities of expensive He.

FYI these gauges are dearer but for a good reason:
http://www.keller-druck.com/home_e/paprod_e/eco2_e.asp

Cathal

WFO
09-06-2016, 03:19 PM
I guess it would depend if they have any quality control, what if they test it before shipping, and as it for hydraulics, use oil.... Cheap Chinese so probably not tested so you may be ok!


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Kinda figured the QC would be suspect at best.

But for the sake of saving several hundred quid I can cope with getting it tested to determine if there are any gain errors in it and factor those in to my blending... not like it is an exact science anyway.

WFO
09-06-2016, 03:20 PM
As the gauge is needed for blending, accuracy is essential. While this gauge is cheap, when you start using it to blend He especially for OC trimix, the gauge inaccuracy could turn into a rather expensive issue with wrong mixes of trimix being produced using large quantities of expensive He.

FYI these gauges are dearer but for a good reason:
http://www.keller-druck.com/home_e/paprod_e/eco2_e.asp

Cathal

And how much are they?

p.s I don't really go for that argument about mega accuracy... if the chinese gauge has an error then just account for it in the usual fudge factors for adiabatic heating/cooling. If you do make a cock of it then ending up with say 17/48 instead of 18/45 makes not hair of a bollocks difference. If I was mixing say 4/90 for silly shit or mixing for a boat full of punters it would be different story.

cathal
09-06-2016, 03:29 PM
And how much are they?

p.s I don't really go for that argument about mega accuracy... if the chinese gauge has an error then just account for it in the usual fudge factors for adiabatic heating/cooling. If you do make a cock of it then ending up with say 17/48 instead of 18/45 makes not hair of a bollocks difference. If I was mixing say 4/90 for silly shit or mixing for a boat full of punters it would be different story.

I bought mine in 2012 for 166. While its dearer a couple of wrong trimix fills in a set of twin 12's would rapidly make up the difference in cost.

WFO
09-06-2016, 03:30 PM
p.s.s don't like that O ring swivel seal feature, think that's fkin daft.... on my oxygen filler thing I got hold of an all monel wetted parts pressure gauge and an inconel 718 needle valve. Better to keep all polymer crap away from HP o2 wherever possible.
I don't even see why these SAP and similar bull-nose fittings have an O ring on.... right next to a high flow instant-on cylinder valve on the J? On the proper industrial regulators all those fittings are brass-against-brass to avoid anything burnable there.

WFO
09-06-2016, 03:30 PM
I bought mine in 2012 for 166. While its dearer a couple of wrong trimix fills in a set of twin 12's would rapidly make up the difference in cost.

twin 12s with trimix in... wash your mouth out and re-do the sums doing 60 bar top offs in a 3l :-P


But still, how much are you going to cock it up by? A few bar each way? 1 difference a fill?

Dave1w
09-06-2016, 04:38 PM
Kinda figured the QC would be suspect at best.

But for the sake of saving several hundred quid I can cope with getting it tested to determine if there are any gain errors in it and factor those in to my blending... not like it is an exact science anyway.

I wouldn't worry too much about the accuracy as you'd figure that out and fudge it, but I'd be concerned that being a hydraulic gauge, they could've just stuck it on an oil line to test it, so maybe not a good idea to hook it up to O2 until you've figured out if it can be cleaned.

gobfish1
09-06-2016, 05:01 PM
80 bar of He , pump to to 260, good for 90m , your over thinking this mixing lark , :rofl:

WFO
09-06-2016, 11:18 PM
I wouldn't worry too much about the accuracy as you'd figure that out and fudge it, but I'd be concerned that being a hydraulic gauge, they could've just stuck it on an oil line to test it, so maybe not a good idea to hook it up to O2 until you've figured out if it can be cleaned.

It's fuckin chinese, what are the chances they've tested it?