ScubaPro 109 Balanced Vs Sherwood Maximus

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

mrarmyant

Registered
Messages
30
Reaction score
17
Location
Dallas
# of dives
100 - 199
I have a rebuilt 109 with MK10 1st and a Maximus with its stock 1st. What is seen as the better setup with regards of where it can dive, reliability, ease of maintenance, etc? I appreciate the metal body and the few parts of the 109, but it's weird to think a design that old can still really be superior to modern tech. I have only used the Maximus, and loved the fins in it preventing the dry mouth, but thought the metal body might do similar. Most of my diving is tropic, soon to be somewhere drysuit esque tho.

Has anyone owned and used both?
 
I'd take a 109 (though I would prefer it to be upgraded to a 156) any day! I own about 15 109/156 seconds. Fantastic regulators. I can't compare to the Sherwood because, for 30+ years, I have been diving 109/156/g250xx stages.

YMMV
 
I'd take a 109 (though I would prefer it to be upgraded to a 156) any day! I own about 15 109/156 seconds. Fantastic regulators. I can't compare to the Sherwood because, for 30+ years, I have been diving 109/156/g250xx stages.

YMMV
Good to hear! I got the kit off vintage double hose which I believe ups it to a 156.
 
It's a loaded question and to you the user they should be equal if both 1st stages are tuned right.
I would just pick whichever one makes you happy to dive with or flash around.

From a service technician standpoint however, a current edition (9000Pro model) Maximus will be able to be tuned to a wider range of easy breathe to hard breath. The 109 takes more of a PITA to get it to do that; sometimes with certain individuals you can't get it to breath light enough without it freeflowing. So that's what the new tech really has improved on. Nothing really noticed by the end user; lots noticed by the technician.

My 109's I can't for the life of me get them below 1.4 inches of water cracking pressure. Now 1.4 is perfectly normal and good but I'm anal about having my regs breath at a 1.0-1.2 inch of water. So I have to put up with that.

The newer tech regs often allows you more adjustment points to change the setpoints for your reg. Sherwood allows adjustment of the orifice and fine tuning poppet spring tension. With the 109 you only have the orifice adjustment and bending the demand lever, which the latter is impossible to fine tune to your naked eye.

So for instance with a Maximus, I can hit any range of setpoints easily and creep gradually from easy breathe to hard breathing. With the 109, I would be jumping gaps from easy breath, moderate, hard breathing. There's not an even spectrum of fine tune adjustment; but when you do get it right it's much more satisfying.

For moisture retention though, I would argue the 109 is better than the Maximus. More metal means greater surface area to condense. The Maximus only have the metal fins and the metal barrel to condense, so far less surface area.

Now if you're talking the older 7000 series Sherwoods (the ones where the 1st stage doesn't do a 90 bend and just comes straight from the tank valve). Then those are exactly equal to the 109 in terms of tuning.
 
I know nothing about the Scubapro to weigh in with a comparison, but sounds like you will soon be diving in temps below 50F and the current Maximus Pro has passed the EU testing for cold water. So if that can't he said for the Scubapro, that would be a clear difference. I don't know one way or the other regarding earlier Maximus versions.
 
A kit from VDH to service a balanced adjustable 109 (156) is $12 and consists of 5 parts, the 109 is very simple and easy to maintain.
 
I dive Sherwoods, although not the Maximus, and on one reg set have changed to a 109/156 primary and use the blizzard as the secondary. I must admit that I do like shiny metal seconds.
Also, it's good to know which Maximus, Sherwood has been using the same names for regs for decades.

but it's weird to think a design that old can still really be superior to modern tech.

The basic design of piston regs has not changed since their inseption, there have been improvements that have made regs better over the years, but for a lot of us those changes do not make a real noticeable difference when diving, especially in rec limits..



Bob
 
I know nothing about the Scubapro to weigh in with a comparison, but sounds like you will soon be diving in temps below 50F and the current Maximus Pro has passed the EU testing for cold water. So if that can't he said for the Scubapro, that would be a clear difference. I don't know one way or the other regarding earlier Maximus versions.

And the 109/156 with its all metal body & barrel is extremely successful in temps in the mid-to-upper 40's. I have used it successfully in the upper 30's diving the Great Lakes for a long time...

The reg will never achieve EU certification as it is no longer in production.

YMMV
 
Would be interested if anyone knows if the low-pressure poppet is the same in both the Maximus and the 109? I've converted a few 109s to the new poppet which hasn't been cheap - but see the Maximus poppet on eBay selling for a song ($2.50...)
 
Well start singing and splash the cash buy one and tell us

The dimensions look identical don't you think

but I found a service guys that gave me some pulled out for no reason ones


Because all the gear you will ever use, will always be "used" second hand
 
https://www.shearwater.com/products/swift/

Back
Top Bottom