Need advice from experienced divers/Techs - MK5 Swivel Turret - VIDEOS INCL! plz help

[ams511]

You can mix and match most regulators (be careful with Poseidon) BUT when it comes to service most dive shops will only service the brands they carry. So if you want an LDS to service the regulators, you would need to find one willing to service both brands. If you are doing it yourself it doesn't matter.

As far as the Highland goes it is the same regulator in both the argon kit and the compact second stage. The main difference is the number of shims they add to boost the IP. I am not sure of the flow rate of this model. I would sooner trust this model: Synchro "P" Regulator Complete Set DIN MODEL

 

[kwinter]

The regulator is deff. not a main to be used all the time. I tested, and it breathes a bit hard (possibly because new?) but for a pony/backup its perfect as I initially intended.

This is a common belief, but I have always found it a bit troubling. While "any port in a storm" is certainly true, there is no reason to specifically plan for a lousy port. Your pony reg would only come into play during an emergency or bad situation. Whether OOG or a problem with your primary gas supply, you are very likely to be stressed if you have to go to your pony (or octo or bailout) regulator. In such circumstances it is vital that it breathe as well if not better than your primary. A stressful situation is no time to be screwing around with a high WOB if it can be avoided. And it can easily be avoided by carrying better emergency equipment. Why would anyone specifically plan to make a bad situation worse just to save a few bucks or ounces?


iPhone. iTypo. iApologize.

 

[halocline]

I would not be concern if it were not for the amount of slop in the turret on the OP's regulator. I have noticed some slop in MK5 turrets but his might be excessive. Could this be the result of necking of the turret bolt? Maybe as mentioned earlier the nylon washer was lost and replaced with thinner one. I think the fact that Scubapro made the MK10 turret bolt at least a hundred times stronger and started making stainless bolts for the MK5 means there is good reason to be concerned.

I'm confident that this is an exaggeration; the SS bolt is certainly stronger, but nowhere near 100 times. The early MK5s used a simple circlip to hold the turret in place, and there are literally thousands of MKs in use today with brass bolts. It's just not a high stress connection. The reason SP replaced the brass bolt with SS was almost certainly to make them more idiot-proof to the technicians who didn't use a torque wrench and just cranked them down. It's not that different than the issue with the MK20 yoke retainers; there were a few instances of MK20 bodies cracking due to bad techs severely over-torquing the yoke bolts and literally splitting the regulator body. SP replaced this retainer with one that 'bottoms out' before an overenthusiastic wrench-wielding he-man can apply enough torque to force the threads to stress the body sufficiently to cause a crack. All it takes is one catastrophic failure and sales of that model will vanish, so SP is very much invested in making their regulators idiot proof to service.

I've pulled at least one MK5 brass turret bolt out that was VERY tight, and saw some damage/stress to the bolts with my jewelers' loupe. Anything like that I would throw away, but ones that are obviously in good shape I use. I was in on the initial order of SS bolts that Zung put together, so I have a handful of them, and maybe as I rebuild my MK5s I'll use them, but I certainly would not bother to take the reg apart specifically to do that. And MK5s can go a loooonnngg time in between services.

But, if it makes the OP sleep better, by all means replace the bolt. I think vintagedoublehose still has them, I'm sure SP does not and I also suspect no SP dealer will use the vdh aftermarket bolt. So its pretty much a DIY option. The unfortunate thing is that a SP dealer observing any visible damage to the original bolt would likely just say "game over" on that reg and move on to the business of selling the customer a new regulator.

 

[NotSure]

I'm confident that this is an exaggeration; the SS bolt is certainly stronger, but nowhere near 100 times.

It probably is an exaggeration even though I was referring to the MK10 turret bolt not the MK5 stainless one. It would be hard to test though because the Scubapro engineers got it right on the MK 10 and used a allen head bolt. I think you would damage the socket of the allen head before you could apply enough torque to damage the bolt. The service record of the MK5 is proof enough that the Brass MK5 bolt is adequate for normal use. I just can't imagine how any engineer could look at such a flimsy brass bolt and think it a good idea to use on such a critical part. I wouldn't want to dive with a MK5 that was serviced by a tech. that doesn't own a torque wrench. If I was going to diy tighten a MK5 turret bolt without a torque wrench I would probably only tighten it finger tight with a nut driver and use a drop of Loctite. The MK5 is an excellent vintage regulator, I just think adding a stainless turret bolt and a shouldered piston makes it a excellent regulator.

 

[ams511]

A stressful situation is no time to be screwing around with a high WOB if it can be avoided. And it can easily be avoided by carrying better emergency equipment. Why would anyone specifically plan to make a bad situation worse just to save a few bucks or ounces?

I blame the dive shops and manufacturers. They empty the newbies wallet by telling him he needs the most expensive regulator because it is life support. Then they palm off the worst second stage for use in an emergency as an octopus. Doing air shares with one in the pool under no stress it was difficult to breath off one of those AL pucks. Under moderate stress I can see over breathing one. Going from a good regulator to a crappy one is like night and day.

 

[SouthFLDiver89]

I blame the dive shops and manufacturers. They empty the newbies wallet by telling him he needs the most expensive regulator because it is life support. Then they palm off the worst second stage for use in an emergency as an octopus. Doing air shares with one in the pool under no stress it was difficult to breath off one of those AL pucks. Under moderate stress I can see over breathing one. Going from a good regulator to a crappy one is like night and day.

Couldnt say it better myself. Great post. They do try and sell you a high end first stage, and a "standard" octo as an emergency backup, while using a $1000 primary. silly

Never personally tried breathing off a "puck" style reg, was there really a noticeable difference? Guess you give up breaking pressure for streamline in those...always thought they look nice and would be a nice backup (octo) Your opinion?

 

[redacted]

It probably is an exaggeration even though I was referring to the MK10 turret bolt not the MK5 stainless one. It would be hard to test though because the Scubapro engineers got it right on the MK 10 and used a allen head bolt. I think you would damage the socket of the allen head before you could apply enough torque to damage the bolt. The service record of the MK5 is proof enough that the Brass MK5 bolt is adequate for normal use. I just can't imagine how any engineer could look at such a flimsy brass bolt and think it a good idea to use on such a critical part. I wouldn't want to dive with a MK5 that was serviced by a tech. that doesn't own a torque wrench. If I was going to diy tighten a MK5 turret bolt without a torque wrench I would probably only tighten it finger tight with a nut driver and use a drop of Loctite. The MK5 is an excellent vintage regulator, I just think adding a stainless turret bolt and a shouldered piston makes it a excellent regulator.

When a swivel retainer with SS threads meets a swivel with brass threads, the swivel will lose.

The shouldered piston just keeps the piston from imbedding itself in the body should the HP seat suffer a catastrophic failure. It is fun getting them separated again,

 

[SouthFLDiver89]

When a swivel retainer with SS threads meets a swivel with brass threads, the swivel will lose.

The shouldered piston just keeps the piston from imbedding itself in the body should the HP seat suffer a catastrophic failure. It is fun getting them separated again,

Because the brass is softer, right? mmm so should the SS nut be used if its not in there already? or keep the brass and get it "torqued" correctly?

 

[halocline]

Because the brass is softer, right? mmm so should the SS nut be used if its not in there already? or keep the brass and get it "torqued" correctly?

Aside from a few high end titanium and SS models, regulators body are brass, meaning the threads in the MK5 turret that the bolt screws into are brass, and as such, softer than SS. Pulling the threads out of the body would take A LOT of force. The bolt is hollow so that air can pass through to the turret. The weakness of the bolt is not that the threads will fail, but that the bolt itself will break if it is sufficiently stressed by over torquing. I suspect that this has happened on MK5s very very very rarely. The SS bolts can handle more abuse, but it obviously is not a big problem to use the brass bolts, despite what anyone might say on an internet forum. Again, there are thousands of MKs out there with brass turret bolts that are successfully used every day and have been for the past few decades. This ain't rocket science.

 

[ams511]

Couldnt say it better myself. Great post. They do try and sell you a high end first stage, and a "standard" octo as an emergency backup, while using a $1000 primary. silly

Never personally tried breathing off a "puck" style reg, was there really a noticeable difference? Guess you give up breaking pressure for streamline in those...always thought they look nice and would be a nice backup (octo) Your opinion?

The price/performance ratio is usually higher in the mid-range of a manufacturer's line. My octos are the same as my primaries. So if I am diving my TX-100 the octo is a TX-50. If I use my G500/MK-20 the octo is another G-500. I prefer adjustable regulators because you can tune them down to prevent free-flows and tune them up if needed. There was a very noticeable difference between my primary and an AL puck. I should have checked the cracking pressure on it.

You had another post that commented on what I said about service. I think you misinterpreted what I said so I want to set the record straight. An LDS can only get parts from the manufacturer for the regulators he sells. So if your rig combines different first and second stages then the LDS needs to be a dealer for both lines in order to get parts. Now some LDSs get around that either by having an arrangement with another shop to purchase parts or use aftermarket parts. Some won't do this because of insurance/liability concerns. That is what I meant when I said they only service the same brands as they sell. I did not mean to imply that they will only service the exact regulators they sold.