normoxic tri mix

[Garf]

I'm going to give this one the benefit of the doubt even though it's set off my troll detector...

The leopoldville is in 57 metres and the Rotoura is in 60 metres. Let's not piss about; unless you're one of those superman-like characters who claims they don't suffer from narcosis, you'd be narked off your tits on air, and you might as well be diving the Stangarth for all you'd remember about the wreck. It's also a waste of time doing dives like that in 12's as you'd only have 15-20 mins on the wreck. There are other options, such as bigger backgas cylinders or bottom stages, but if you've only just passed a nitrox course, and you found the nitrox course hard, then you're realistically not ready for the dives you are talking about. Get some experience in shallower wrecks first and then set those deeper wrecks as targets for a future date. They will still be there.

[jcsp]

I am in no means Trimix qualified so take this with a pinch of salt.

The Helium in Trimix allows you to reduce the effects of the other gasses as Helium will be mixed with both Nitogen and Oxygen.

In Trimix O2 usually has to be added to set the percentage of O2 desired.

So as such it allows you to pick your equivilant air depths as with Nitrox, there are just more Variables.

Due to the cost of O2 and Helium trimix can be expensive.

My advice to you would be to set these wrecks as goal targets and get experience using Nitrox, as both back gas and deco gasses. There is a difference using it in training circumstances and none training circumstances.

As to begin with I believe you will be using "tables" and run times I think it would be advantageous to start writing small dive plans on a slate and use them so you can get used to it.

The information on a slate gives you a maximum depth you can go to and how long to stay there. Followed by the deco obligations required and the ascent speed.

I seem to remember that a certain 10m/min ascent rate would be good to practice both with and without dsmb's from what i have heard.

Dive within your limits and to build up to the qualified depths, remember the wrecks wont go anywhere but you may.

Forgive me if this is inapropiate but what sort of skill level are you. eg Dive Leader/Master. And how many dives have you done?

Trimix like Nitox can be a safe gas but it can also bite you in the ass. The particular bite being bigger due to the depths usually involved with trimix.

[Hazel W]

name and address of the gas supplier please ......thats unbelievably cheap

with the stress on the word unbelievaby

H

[Garf]

Originally Posted by Hazel W

name and address of the gas supplier please ......thats unbelievably cheap

with the stress on the word unbelievaby

H

and the words "and somewhat suspiciously" inserted between the words "unbelievably" and "cheap"

[clockworkdog]

Originally Posted by Garf

I'm going to give this one the benefit of the doubt even though it's set off my troll detector...

Defeaning silence from the troll!!! It's a troll, it's a troll, it's a troll! Does YD record IP addresses?? - Will it match someone else on here?

[Bardo]

Originally Posted by Howard Payne

About 104 bar of helium then about 19 bar of 02 topped with air
Thats around 1250 litres of helium at around 2p a litre = 25 quid
Plus around 230 litres of o2 at around 1p a litre - 2 quid fifty

With an air top around 30 quid in total - assuming you don't have a friendly LDS who does it for less

If you can buy is for 12 quid - please let me know where!

Why?

Yer go... here's the output from my jolly little gas blending application that I use to blend gas...

BBLENDER 1.10
Copyright © Bardo 2007
Mix Settings...
* Required Mix = Trimix 18/45 @ 230 bar
* Cylinder Size = 2 x 12.0 litre twinset

Blending instructions...
* Add 103.5 bar (2484 litres) of Helium
- New Pressure = 103.5 bar
* Add 18.78 bar (451 litres) of Oxygen
- New Pressure = 122.28 bar
- Oxygen Reading = 15.4%
- Helium Reading = 84.6%
* Add Air to max pressure of 230 bar

Gas Information...
* Max Operating Depth @ 1.4 PO2 = 67 m
* Max Operating Depth @ 1.6 PO2 = 78 m
* Equiv Narcotic Depth @ 1.4 PO2 = 27 m

Cost Analysis...
* 451 litres of Oxygen
Cost £ 2.00 flat rate = £ 2.00
* 2484 litres of Helium
Cost £ 0.016 per ltr x 2484 = £ 39.74
* 2585 litres of Air
Cost £ 3.00 flat rate x 2 = £ 6.00
-------
COST OF FILL = £ 47.74

These prices are based upon what you'd typically pay at a place like Vobster that charges 1.6p per litre for He, a fixed rate of £2.00 for oxygen and standard rate for air top. Some places charge 0.5p per litre for oxygen which - whilst more accurate - has very little effect (we're talking less than 9p on top of the total cost of the fill). This is also the price for a twinset so half it to get a comparitive price - ie. £24 - and you're still looking at double what our friend on ebay is offering it for!

[EDIT] - Based upon his price of £12 for a 12 litre fill of 18/45, this guy is effectively charging just 1p per litre for He - and that's assuming that he's not charging for the O2 and air top! If you factor in the cost of the O2 and air, the cost of the helium drops to 0.6p per litre which is *waaaaaaaay* below what it costs from people like Linde and Air products...

[oceanobsession]

Originally Posted by Hazel W

name and address of the gas supplier please ......thats unbelievably cheap

with the stress on the word unbelievaby

H

hi hazel derby diving is youre man tel no 0800 7834804 ebay item no is 7223574689 cheers hows fred brown these days

[clockworkdog]

Originally Posted by clockworkdog

Defeaning silence from the troll!!! It's a troll, it's a troll, it's a troll! Does YD record IP addresses?? - Will it match someone else on here?

Now that's why we don't have the death penalty any more.... I was just bluffing

[NeilB]

Originally Posted by Bardo

[EDIT] - Based upon his price of £12 for a 12 litre fill of 18/45, this guy is effectively charging just 1p per litre for He -

....and what's wrong with that? That's what I pay for my He.

a 44l of He costs 30 rials = £39 at current exchange rates.

[Garf]

Originally Posted by oceanobsession

hi hazel derby diving is youre man tel no 0800 7834804 ebay item no is 7223574689 cheers hows fred brown these days

I'm gonna call at 9am. If this is above board, I'll drive up there at the weekend in a couple of cars with 30 cylinders for him to fill. However, something tells me I shouldn't bother making any plans...