Trident DIN Converter for Scubapro

[Zung]

Gentle Folks,

I've just got a Trident A194 DIN converter for newer SP regs. I tried it on a MK10 and it fits OK. It even has the additional ring and the "bump" reg side to prevent overtorqueing from breaking the MK20 body.

The problem is: I can't figure out how to remove the air filter that's inside; I can see it from the reg side, I tried to poke it from the other side with a chopstick, but it doesn't work. It doesn't have the filter retainer like the original SP part.

Does anybody know? And is it a regular SP filter (01-028-109), or is it one of Trident's own, the A164 maybe?

Or is it a single use/throw away item to be replaced at very service?

Thanks.

 

[halocline]

It's probably like the older style SP, there's a metal washer/spacer that fits between the filter and the o-ring that seals against the reg body. Maybe that washer is kind of tight, but you should be able to pull it out with an o-ring pick.

Awap tried one of the trident retainers once and said it felt a little tight. Did you have that experience?

 

[knowone]

What bump. Or does it have a 4 mil allen key filter retainer.

 

[Zung]

The bump that's right of the #2 arrow, top pic.
And no, it doesn't have a filter retainer like the SP parts.

mattboy:
The fit is OK to good, not great; because of some mishandling, there're 3-4 slight nicks on the threads reg side, so the installation is not "buttery", and there seems to be 1 less thread than the SP part. Nevertheless, I can screw it all the way in with 2 fingers and no forcing. I'll make some measurements and post some pics later in the day.

The prob is, I looked at the thing any way I can, and could see no retainer, no rivet, no clip, no nothing for the filter. If the sun comes up (unlikely), I might be able to post a pics of the inside.

 

[halocline]

If there's an o-ring in the reg end of the retainer, take it out, then see if there's a metal washer/spacer underneath it. If the hex fitting on the outboard side is 6mm like the older style SP retainers, that's how the filter is held in place.

 

[Zung]

Nope, it doesn't have anything either end, but 1st thing 1st:

• Pic1: A194-SP.jpg is a comparison between SP (232 bar, left) & Trident (300 bar, right). There are minor differences, but the threaded parts match almost exactly, except for 1 less thread.
• Pic2: A194-Body.jpg is the body; it's in 1 piece
• Pic3: A194-Reg.jpg is the reg end minus the o-ring. Notice the "bump" at the top. You can see the recessed filter in the middle; and you can guess the diameter of the filter is a bit larger than the opening, so it won't get in this end.
• Pic4: A194-DIN.jpg is the DIN end. You can see the Allen "hole" (whatchacallit?) for a 6mm Allen key. The opening is even smaller than the reg end.

The options that I see are:

1. The filter is forced in from the reg end, but I don't see any tell tale scratches in there.
2. There's some mechanism hidden beneath the o-ring DIN end. But that would compromise the sealing wouldn't it?

I've been wrestling with that o-ring for a while without success. I'm trying to make up my mind to sacrifice it to look underneath. Should I?

Edit
Here's some numbers:

Outside diameter of the threads, reg side:
- SP: 15.9 mm
- Trident: 15.8 mm

Outside diameter of the threads, DIN side:
- SP: 22.7 mm
- Trident: 22.8 mm

Distance from the tip to the base of the 1st ring:
- SP: 7.8 mm
- Trident: 7.7 mm

Height or length of the Trident air filter: 12.3 mm.

The last measurement indicates that the filter is Trident specific, and not a SP one which is 19.8 mm. That makes the Trident less attractive because there's the cost of the filter on top of the service kit.

 

[DA Aquamaster]

The filter did not grow there.

The reg end of the fitting should have a fairly thick washer or bushing that sits on top of the filter. It should come out. Looking at picture 3, it appears the inset portion is not just milled in the end, but rather there is a line where the parts join.

If the tank end of the fitting is threaded for a 6mm allen wrench, then it is most likely intended as the sole means to tighten the fitting, as a fitting that size is a bit large to just secure an insert, but if it is intended to tighten the fitting, I'd expect the hex portion of the fitting to be a little deeper.

So there is either a bushing on the reg end that comes out, or there is an insert on the tank end that screws out. If the latter is the case and it is stuck, you'll need to unstick it.

 

[Zung]

Update:

I removed the o-ring at the tank end by completely destroying it: it's glued. Sadly, there's nothing in there, just a solid chunk of metal.

DA is right (of course!), there's a line along the inside circumference at the reg end which is not a mill mark. That line is about 2mm from the tip, but it doesn't show on the outside, so I still don't see how the "assembly" is done.

Btw, I made a mistake in my measurements, and the filter is actually 2.1mm thick, which could match Trident's A164 "DIN filter", 2.05mm H by 8.95mm wide.

The diameter of the body is 17.4mm, the opening reg side is 5.3mm, and the DIN side is a 6mm Allen. The inside of the body is wider than the opening, but it's near impossible to measure. Anyway, the thing cannot be fabricated this way, there has to be a way to break it apart.

Still investigating....

 

[redacted]

I would expect the filter retainer to unscrew just like with the SP newer din design. That allen connection in pic 4 looks way to thin to take the kind of torque used to attach a din connector to the reg body. It has to just hold in the filter and the o-ring.

The "old style" trident din converter has the filter inserted from the bottom just like the Mk10 din. It was not compatible with the Mk5 as I had hoped. So I'm assuming the "new style" should be like newer style SP din converters.

 

[redacted]

I took another look and, I can't tell for sure, but is that a small flat surface in pic 3 on the bottom radius that might engage an open end wrench? If so, the allen wrench on one end and a box end wrench on the other might reveal the secret.