Dive computer battery and o-ring spec's

[Rooster59]

O-rings also come in different hardness, 70-durometer is softer than 90. I think dive computers would be 70's, 90's are pretty hard/stiff.

 

[Peter69_56]

British Standard and Aerospace Standard do not exchange directly. If your measurements are in inches. That would be an AS size -028

More important is the British pint vs the American pint. I look for pubs in the US that serve beer in British pints.

Yes the measurements are in inches. It appears that both AS and BS028 are the same size O ring (from all the data I can get from internet. I compared

Eriks O ring chart http://o-ring.info/en/technical manual/ERIKS - Technical Manual - O-Ring Size Chart.pdf which is AS and

Par group which is BS BS O-Ring Dimensions | Products | PAR Group

I can't see a difference so I guess either will do.

yes I agree with the British pint

 

[DiveGusto]

Yes should be the same. O-rings sizing spec'd on fitting the ID which for the -028 is 34.65mm +/- 0.33 or 1 3/8 in. w/c.s. 1.78mm +/- 0.08 Fitting the o ring with very slight stretch to keep the c.s. close to original spec is key.
I was measuring an old calypso aqua lung depth gauge that I want to reseal and dive, came up with 1 5/8 ID on the crystal so going with a -029, anyone have experience here.

 

[BenjaminF]

D'oh.....OK, I see what you mean. Measure the diameter of the cap that seals the battery case or the groove in the computer's housing. The cap should give you the i.d. & the housing groove the o.d.

By the way, unless you have a new o-ring, it's usually not a good idea to get the dimensions from the seal as they can stretch and distort. I do however, like Awap's dimensioning cone. Drop the seal over it and measure the diameter of the cone where the o-ring rest.

You mean that wasn't a dunce cap just for me?

It's a new o-ring. I picked up a battery replacement kit when I got the computer, so that I would have a "spare". Just in case. Yes, I know. I have a problem when it comes to having spares

If I can't get an accurate number from a home-made cone, would simply flattening the o-ring and then measuring it's length also give an accurate number?

 

[Zung]

Here're the charts - Please proof it within 24h, after which they'll be locked down for eternity.

View attachment Computer Batt & O-ring V1.1.xls
View attachment Computer Batt & O-ring V1.1.pdf

 

[Couv]

You mean that wasn't a dunce cap just for me?

It's a new o-ring. I picked up a battery replacement kit when I got the computer, so that I would have a "spare". Just in case. Yes, I know. I have a problem when it comes to having spares

If I can't get an accurate number from a home-made cone, would simply flattening the o-ring and then measuring it's length also give an accurate number?

Perhaps you are over complicating the process. If you have a new o-ring, just lay it on a flat surface and measure the i.d. and cross section. But Awap's cone is pretty fool proof. Just drop it on the cone and draw pencil marks over and under the seal. Measure the diameter around the cone between the marks.

---------- Post added September 18th, 2013 at 06:29 PM ----------

Here're the charts - Please proof it within 24h, after which they'll be locked down for eternity.

View attachment 166440
View attachment 166441

Thanks Brother Zung.

Per Zung: Aladin Pro, 1st generation, with no oil:

• LS14500, soldered
• 2-016, no lube (chart shows 2-012)

Everything else seems to be correct according to the post.

 

[Peter69_56]

What is the 2 before the O ring number?

 

[redacted]

It is size series designation used in the US.

This is the bible (USA version): http://www.parker.com/literature/ORD 5700 Parker_O-Ring_Handbook.pdf

 

[BenjaminF]

The Oceanic OCS o-ring is 120mm in circumference (on the inside) using Awap's method. That gives me an inside diameter of about 38.1972mm (38.197186342...). It is 1mm thick. Not a "hard" o-ring. It bends under it's own weight fairly easily.

 

[redacted]

I seriously doubt if Oceanic would use a non-standard O-ring. It adds unnecessarily to the production and service costs. And it is so easy to simply design for a standard 2-xxx o-ring in such an application. Based on your measurements, I suspect you are looking at a 2-029.

I would use the cone by placing the o-ring about level on the cone (just to make sure it is "round") and then use your caliper to measure the outside diameter at a couple points. A 2-029 is 1 5/8 inches OD, 1 1/2 ID, and 1/16 wide. (37.82mm ID and 1.78mm wide)