Taking apart a Scubapro MK5 - what tools do I need?

[boat sju]

@rsingler , I think the Scuba Museum has stainless steel turret bolts.

 

[lowwall]

You'll need to get creative to remove and replace that turret bolt. A friend who will grind the chamfer off an 11/16" deep socket, and grind the outside wall until it slips into the gap between the cap and the bolt head.
View attachment 834084

I made my own by buying a thin wall socket and hand filing the chamfers off. It took maybe 10 minutes. You can see it on the socket wrench in the middle of this photo.

These are all the tools I assembled for @rsingler's course. A couple of them are specific to Mares' regs. One nice discovery was that the Mares yoke wrench (to the right of the socket with "25" stamped on it) works for ScubaPro as well (see below). You could make the cutout that makes this work with a grinder or even a file.

The double hook pick mentioned by rsingler is the one with the blue handle at the left. And you can see a bolt that was converted to an HP port holder among the wood dowels.

 

[Bigbella]

I made my own by buying a thin wall socket and hand filling the chamfers off. It took maybe 10 minutes. You can see it on the socket wrench in the middle of this photo.

View attachment 834095

These are all the tools I assembled for @rsingler's course. A couple of them are specific to Mares' regs. One nice discovery was that the Mares yoke wrench (to the right of the socket with "25" stamped on it) works for ScubaPro as well (see below). You could make the cutout that makes this work with a grinder or even a file.

Where's your conspicuously-missing suturing kit?

 

[rhwestfall]

One nice discovery was that the Mares yoke wrench

Where/how did you get that?

 

[lowwall]

Where/how did you get that?

I bought the wrenches and the white seat tool, along with several service kits, from @Charlene Barker's dive shop Aqua Sport Scuba Center in Calgary.

IIRC, her shop had stopped selling and servicing Mares gear so the tools were just sitting around gathering dust and they could no longer keep her from selling off parts she had in stock. She still has quite a few parts and service kits remaining. No tools though. Prices are in Canadian dollars.

Search: 55 results found for "Mares"

online recreational technical scuba diving and snorkel equipment

aquasportscuba.com

 

[Diverspoint]

To remove the HP seats I use a watch tool.

Like this one. I use the big adjustable spanner on the right

 

[jellycatsdad]

A good tool or seven makes it fun, instead of frustrating. Thanks for being a good sport.

In that particular case, a CO2 cartridge is pure Vance Harlow. Nothing wrong with that. A cheap 7/16" fine thread bolt is even better, as long as you drop by an auto shop and ask them to throw a die on it and de-burr the threads. Two minutes work.

It's that yoke removal tool that gets you into trouble. Going low tech? Grab a BIG wrench like @boat sju said. One whose jaws reach all the way across the flats. But yes, there's a $40 specialty tool for every function that makes things easier, at a price.

That bicycle castle nut spanner is a great inexpensive alternative to a hook spanner. If the diameter is too large, pad the heel.

But the one critical tool you'll need is a $2.75 double hook pick to remove the HP piston shaft o-ring without scoring the land. The standard shop tech technique of spearing it and prying it out is an invitation to a perfect repair, except that the ambient chamber holes now bubble lightly, because that HP o-ring land is now scratched. Scubatools or Piranha.
Two dowels, one 1/4", one thin, to put the o-ring back in.

Carve a piston bullet from a 1/4" dowel with your pen knife.

Angelo's right angle pin pliers, or a small pin face spanner from Scubatools.com.

An air gun or this trick
Post MK10 Rebuilding Mods and Best Practices
to get out the HP seat.

A plastic dental toothpick to lift out orings.

You'll need to get creative to remove and replace that turret bolt. A friend who will grind the chamfer off an 11/16" deep socket, and grind the outside wall until it slips into the gap between the cap and the bolt head.
View attachment 834084
But remember, that turret bolt is only 35 in-lb of torque on reattachment, if it's brass. Easy to break, impossible to replace now that VDH has closed after Bruce's death.

You're all set without breaking the bank.

I had to reread this a few times, there’s good info here! I have access to a bike pin spanner, though my friends at the local bike co-op will look at me weird working on scuba gear at the shop .

Will a Harbor Freight 20-200in-lb torque wrench I normally use for bike and some car fasteners work, or get something a bit more precise?

 

[rsingler]

Will a Harbor Freight 20-200in-lb torque wrench I normally use for bike and some car fasteners work, or get something a bit more precise?

Sure! It's fine, if a hair light for the Yoke bolt, which is 235 in-lb (disregard the schematic - it was revised downward in later years).

And you can calibrate it by using a $15 luggage scale. Clamp it in a vise, and see how many lbs. are required to click it at various settings, and make a table or graph.

 

[halocline]

You technically can remove the yoke retainer with a vise or big adjustable wrench, but I assume you’ll want to put it back together, and get at least in the ballpark for the torque spec. That means a yoke nut and torque wrench. In a pinch, I have fixed regs in the field and just guesstimated the torque, but I wouldn’t make that a practice. It’ll work to keep diving on a trip but it’s best for the reg long term to not exceed the torque. I read someplace that studies have shown mechanics almost always over estimate torque when tightening by ‘feel’. What you are trying to accomplish is to have it tight enough so that it doesn’t come loose when someone picks up the tank by the regulator that’s attached, but not so tight that you’re stressing the soft brass.

R Singler is right on the money with the double hook o-ring pick, I don’t know how I’d get the HP o-ring out without one. I still bury the point of the pick in the o-ring to get it started coming out, but it’s much, much easier and safer to accomplish this and avoid scratching the reg body using the the double hook.

I think the SP tool is worth getting; it does a few things and isn’t very expensive, or at least it didn’t used to be. I bought mine 20 years ago at least from scuba tools. It’s not the best tool for loosening the body/ambient chamber because sometimes those threads can get very loaded up with residual salt and be true misery to get un-stuck. I’ve resorted to freezing/boiling/freezing etc to get them loose. I think about that every time someone posts about not soaking their regs because they’re worried about water getting in the inlet. Anyhow, the SP tool does work for it but with the really tight ones, something bigger with a more aggressive pin would be better.

 

[rsingler]

@halocline is spot on! Those numerous techs who guesstimate their torque inevitably lead to impossibly tight bolts once saltwater is forced into the threads at depth and verdigris sets in after two years.
But if a $200 dial type torque wrench is out of your budget at this point, you can still do a good job with a big-ass wrench, a $15 luggage scale and your cell phone calculator.

230 inch-pounds required divided by a 14.5" lever arm, yields 15.9 pounds required pull on this wrench. The bigger the wrench, the easier it is to handle, but @lowwall 's wrench will work just fine here too! Just don't one-hand it like this picture. Keep control of the jaws. And pull at a right angle to the wrench.