SMS75 enough lift?

[psdiver102]

I dive mine with 2 Worthy LP85's, single Al80, and a 40cf deco. I use a 3mm shorty, 5mm long, or a Bare HDC. I recently used it in single tank back mount with steel 100 and Al single tanks for spearfishing and it worked well. Oh yea, my second dive was with double back mount steel 100's. It's all about how you feel with it and if you have support starting out from people who can help you set it up. If you look and the Katana, I put those attachment points on my 75 right at the start for AL tanks. Also got rid of the big plastic buckles in the front that take up so much room

 

[tbone1004]

yes, it's more than enough, but please try to refrain from creating duplicate threads, it isn't necessary.

2x 100's=16lbs of gas
2x 40's=6lbs of gas

with a drysuit with heavy undergarments we are assuming you are diving a balanced rig, and in that case the rig only has to compensate for the 22lbs of gas. In the event of a suit flood, you essentially become completely neutral and it now has to cover the rest of the load which is an extra potentially 14lbs for the 100's *if they're Worthington's which are super heavy, more than likely it will be 10lbs*, and 10lbs for the al40's assuming everything is full which it won't be. This is cutting it very close since the 75 actually has a bit more lift than I think Hollis claims, but you can always dump the 40's or one of the 100's if you have to.

What I'm curious about is why you have 2x 40's? If one is O2 which I assume it is, what's the other for? If it's for a deep deco since the 100's are trimix, then you are more than OK because the 100's will have less mass than nitrox and you'll burn through that gas pretty quick.

 

[uncfnp]

He posted here at my suggestion when he wasn't getting many responses in the advanced forum and none that really addressed this specific concern. I agree a better choice may have been to ask the mods to move the thread but I think now he has his answer.

 

[boulderjohn]

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A ScubaBoard Staff Message...

Two threads on the same topic have been merged.

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[Bigeclipse]

yes, it's more than enough, but please try to refrain from creating duplicate threads, it isn't necessary.

2x 100's=16lbs of gas
2x 40's=6lbs of gas

with a drysuit with heavy undergarments we are assuming you are diving a balanced rig, and in that case the rig only has to compensate for the 22lbs of gas. In the event of a suit flood, you essentially become completely neutral and it now has to cover the rest of the load which is an extra potentially 14lbs for the 100's *if they're Worthington's which are super heavy, more than likely it will be 10lbs*, and 10lbs for the al40's assuming everything is full which it won't be. This is cutting it very close since the 75 actually has a bit more lift than I think Hollis claims, but you can always dump the 40's or one of the 100's if you have to.

What I'm curious about is why you have 2x 40's? If one is O2 which I assume it is, what's the other for? If it's for a deep deco since the 100's are trimix, then you are more than OK because the 100's will have less mass than nitrox and you'll burn through that gas pretty quick.

Yeah sorry Tbone. I was told to maybe try in the Sidemount specific forum. I should have asked if a moderator could have moved my thread.

As for your question about two 40s, honestly I just started intro to tech so I don't know much. All I know is what I have read and that a lot of people will dive with 100% in one 40cu and 50% in the other. As for what dives/circumstances these would be used on, I do not yet know.

 

[Bigeclipse]

So it sounds like it should work for what I want? Again, like everyone has stated....assuming I am diving a balanced rig? My concern was mainly the initial splash from the boat and making sure the wing could float me with my head above the water with two steels and deco gases

 

[Stoo]

I have a virtually unused SMS 100 I would part with! I got caught up in the SM bandwagon, but concluded that it wasn't the best for me since I dive out of a RHIB most of the time...

 

[Bigeclipse]

I have a virtually unused SMS 100 I would part with! I got caught up in the SM bandwagon, but concluded that it wasn't the best for me since I dive out of a RHIB most of the time...

I found an excellent deal on this sms75 complete with bottle rigging and virtually brand new. What could you do and what does it include? And mods made to it?

 

[Stoo]

I bought it used from a guy who used it twice. Ultimately, he opted for to get a SMS75 since he only used it in warm water.

I have never used it. It's been hanging on a peg since the day I brought it home! As far as I know, no modifications have been made. It looks brand new. Bungies etc are there, but beyond that, there doesn't appear to be anything "extra", like weight pockets.

If you have any interest, I can take a couple of pics on the weekend and send them to you. It lives at my place in Tobermory...

 

[Bigeclipse]

I dive mine with 2 Worthy LP85's, single Al80, and a 40cf deco. I use a 3mm shorty, 5mm long, or a Bare HDC. I recently used it in single tank back mount with steel 100 and Al single tanks for spearfishing and it worked well. Oh yea, my second dive was with double back mount steel 100's. It's all about how you feel with it and if you have support starting out from people who can help you set it up. If you look and the Katana, I put those attachment points on my 75 right at the start for AL tanks. Also got rid of the big plastic buckles in the front that take up so much room

I just checked Hollis owner manual for the SMS 75 and it states it can do one 20Liter tank or two 15 Liter tanks. I think it should be ok for 2 steel hp100s and 1 deco bottle but not sure about 2 deco bottles, however, you said you have no issues with 2 LP85s, with a single AL80 (stage?) and 40 deco all at one time? Those LP85s should be similar to my HP100s. When you dive that in your bare HDC for cold water, did you need any extra lead? if so how much and did you feel the wing was plenty of lift? Thanks!