Question About Apeks DS4 DIN 1st Stage Regulator: Are These O-Rings for G5/8 Shaft Compatible?

[Brian Pasic]

I have an Apeks DS4 - DIN 1st stage regulator and recently learned these have so called G5/8 shafts. I am looking to replace the special DIN fitting O-rings and found some available here..

They mention that their O-rings are designed to fit the slightly smaller O-ring groove found on Apeks DIN first stage regulators. I’m wondering if this applies to my Apeks DS4 regulator specifically, and whether this smaller groove is common across all Apeks DIN regulators. Is the G5/8 shaft referring to these smaller grooves on all Apeks first stages?

Thanks

 

[steinbil]

I don't know exactly what they're referring to the the groove being smaller - smaller than what?

In any case, I can confirm that the DS4, DST, FST and FSR all use the same tank-facing DIN O-ring. Not sure about the supplier you linked, but this is a pretty standard O-ring among many DIN first stages, so I don't think you could go wrong as long as the O-rings are of decent quality.

Edit: Typo

 

[Umuntu]

The Apeks DIN O-ring is a -111 with 90 durometer; the standard DIN O-ring is a -112.

The diameter of a -111 O-ring is smaller than a -112, because the groove at the tip of the DIN turret has a smaller diameter.

 

[steinbil]

The Apeks DIN O-ring is a -111 with 90 durometer; the standard DIN O-ring is a -112.

The diameter of a -111 O-ring is smaller than a -112, because the groove at the tip of the DIN turret has a smaller diameter.

Good to know! Most divers around here has Apeks or Scubapro, so I haven't come across the other size O-ring.

 

[Centrals]

111 is slightly smaller than 112 so the description is accurate.

 

[Brian Pasic]

Ok great - good to know!!

 

[mr_v]

@Brian Pasic DS4 will take 111 or 112 depending on whether you want to stretch a smaller o-ring (111) or squeeze a large o-ring (112).

If you choose to go with 112, it may pop out. Watch out.

If you go with 111, Dura 90, you may have to replace it more often, as the ring will deform easier.

ScubaGaskets sold a DS4 DIN o-ring that was in-between sizes and it fit well, but I can't find the part number.