Question Scubapro MK20 swivel retainer failure questions.

[happy-diver]

Yes chief

 

[happy-diver]

Today I'm sorting stuff out, it's coming out of the dozens and dozens of storage containers

and going into millions of resealable bags then into storage as bags store more than boxes

Why have all this spare stuff, does not this spare stuff already come installed within the regs

and also included at no extra cost, unique patches of rust suggesting steel, never to be used.

 

[Diver Stan]

Interesting discussion. Humm, bags of retainers? Email me. I have been shorting steel and buying rust futures.

By the way, I could not find the nylon retainer gasket that was missing from one of the regs. But I did purchase a bag of 100 similar gaskets (under $1 discontinued) with the correct OD but slightly smaller ID. After several attempts to drill or punch out the center unsuccessfully--hence the 100 gaskets--a Dremel did the trick. Not perfect but does make a stable gasket that works fine.


Cheers everyone.

 

[Decotek]

The August 98 schematics are the first to show the swivel retainer as 10-500-104 (stainless steel with the original 4-5Nm torque) the 10-500-103 (Brass with original 55-70 in lb torque) was used on the early series from start of production in 95 to early 98. The problems arose from people overtorquing and causing the swivel retainer to fail. I had one fail on a dive at about 40m, it became an interesting day. Attached is a blowapart showing relevant torques and material options from 2005.

 

[axxel57]

The August 98 schematics are the first to show the swivel retainer as 10-500-104 (stainless steel with the original 4-5Nm torque) the 10-500-103 (Brass with original 55-70 in lb torque) was used on the early series from start of production in 95 to early 98. The problems arose from people overtorquing and causing the swivel retainer to fail. I had one fail on a dive at about 40m, it became an interesting day. Attached is a blowapart showing relevant torques and material options from 2005.

Yes, almost correct.
SP implemented the 10.500.104 SS Retainer Screw quite earlier than 08-98, but it was used only in the MK20UL 1sts AFAIK, probably to avoid galling.
So they had them already at least in the early '97.
I guess, after later some problems with the brass screw showed up, they decided to use the probably more expensive SS screw for all their actual brass 1sts with turret.
The first time the SS screw is shown in a brass 1st might be the April-98 MK18 schematics that I found now, but who knows.
Anyway, I guess we have pretty well narrowed down the time frame within the SS Retainer Screw was implemented for the different models.

 

[Couv]

Let us rewind to the days of yesteryear and look at the history of this swivel retainer. Way back in 1984 (if not before) the swivel retainer, part number 10-500-103, was used in the MK10. Back then, the torque value was listed as 55-70 inch pounds. The MK10 parts diagram Rev Date 09/94 shows a reduced torque of value of 35-45 inch pounds* Around mid 1998 a new part number, -104, appeared in the MK10 parts diagram. It was noted as stainless steel but still had the same torque value (35-45 inch pounds.) Later we see both retainers listed. However, the torque values for both brass and INOX (stainless steel) are then revised to 35 inch pounds and 70 inch pounds respectively.

Fortunately for us, the retainer (10.500.104) is still used today in the MK25. It is backwardly compatible with the MK10/14/15/18/19/20/25

*Probably an indication of when there was a known issue.

Disclaimer: I do not have all of the Scubapro documents to support the above and I welcome any corrections.

 

[Couv]

BTW @buddhasummer is making an order for parts. He can probably get the swivel retainers:
10.500.104 and retainer washers 01.060.500

See this thread:
For Sale - Apologies and order (?)

Better hurry as the door is closing.

 

[buddhasummer]

BTW @buddhasummer is making an order for parts. He can probably get the swivel retainers:
10.500.104 and retainer washers 01.060.500

See this thread:
For Sale - Apologies and order (?)

Better hurry as the door is closing.

I have put in a request for prices on those 2 items. Dealer hit with Covid so things moving a bit slow, there's still time...

 

[boat sju]

@Diver Stan You'll have to scratch the surface to determine if you have a SS or brass retainer. (Actually, I hope someone has a better way.)

I've been watching Curse of Oak Island. All you need is a XRF analyzer.

 

[rsingler]

Fortunately for us, the retainer (10.500.104) is still used today in the MK25. It is backwardly compatible with the MK10/14/15/18/19/20/25

Note that this does not include the Mk19EVO, which has a 7mm hex instead of 7/32".
That swivel is 10.719.105