Dacor Nautilus

[WD8CDH]

So, your a Vintage Diver, not a Vintage Equipment diver.

 

[vintagediver]

So, your a Vintage Diver, not a Vintage Equipment diver.

Yes to both categories....

 

[WD8CDH]

Me too. I bought most of my Vintage Equipment new.

 

[AfterDark]

I'm a very experienced diver with well worn equipment. Or a well worn diver with very experienced equipment...darn used to know how that went

 

[John C. Ratliff]

Okay, I do have to say a few things here on the Dacor Nautilus. It actually is a very well-designed BC, and way ahead of its time. It is best used with a full wet suit, as the wet suit looses its buoyancy as you dive deeper, and the thicker the wet suit, the more pronounced this loss. Dacor had a very good training program, and required each diver who bought one to go through the training. They also placed serial numbers on their units. I have two, one with and one missing its regulator (the inflator system is actually a regulator which keeps the unit at ambient pressure). The concept is to be neutral at the surface with the unit full of water. It can be brought to the water without wearing it, and easily donned in the water by opening the valve and flooding the unit about 3/4 way full of water. It will sit vertical in the water when it is in this configuration, and easily donned.

Being neutral, you can dive to about 40 feet, where just about all the wet suit compression will have taken place, and use the BC to attain neutral buoyancy by opening the bottom valve, and adding air. Then, by closing that bottom valve, you create a closed system. You can then descend as far as you want without adding more air, as the regulator will automatically add air. You can also ascend from below, and the unit's overpressure relief valve will vent the excess air. You don't have to do any monitoring of the air in the system--it is truely a "constant volume system" or CVS, as Dacor called it. From 40 feet to the surface, you can again not do much, as the system doesn't expand like a regular BC; the volume is constant. You will get somewhat more buoyant near the surface, but nowhere near like a regular BC.

This was a unique system, and I am still actively using it. It performs well in current in the Clackamas River too. And no, Scubapro did not have a similar system; they just put a cowling around a wing...theirs was not a constant volume system. Dacor's CVS was the only constant volume system that I know of on the market. White Stage and one other firm had a rather similar system--smaller, but open to the water and, again, not a constant volume system.

SeaRat

 

[AfterDark]

Okay, I do have to say a few things here on the Dacor Nautilus. It actually is a very well-designed BC, and way ahead of its time. It is best used with a full wet suit, as the wet suit looses its buoyancy as you dive deeper, and the thicker the wet suit, the more pronounced this loss. Dacor had a very good training program, and required each diver who bought one to go through the training. They also placed serial numbers on their units. I have two, one with and one missing its regulator (the inflator system is actually a regulator which keeps the unit at ambient pressure). The concept is to be neutral at the surface with the unit full of water. It can be brought to the water without wearing it, and easily donned in the water by opening the valve and flooding the unit about 3/4 way full of water. It will sit vertical in the water when it is in this configuration, and easily donned.

Being neutral, you can dive to about 40 feet, where just about all the wet suit compression will have taken place, and use the BC to attain neutral buoyancy by opening the bottom valve, and adding air. Then, by closing that bottom valve, you create a closed system. You can then descend as far as you want without adding more air, as the regulator will automatically add air. You can also ascend from below, and the unit's overpressure relief valve will vent the excess air. You don't have to do any monitoring of the air in the system--it is truely a "constant volume system" or CVS, as Dacor called it. From 40 feet to the surface, you can again not do much, as the system doesn't expand like a regular BC; the volume is constant. You will get somewhat more buoyant near the surface, but nowhere near like a regular BC.

This was a unique system, and I am still actively using it. It performs well in current in the Clackamas River too. And no, Scubapro did not have a similar system; they just put a cowling around a wing...theirs was not a constant volume system. Dacor's CVS was the only constant volume system that I know of on the market. White Stage and one other firm had a rather similar system--smaller, but open to the water and, again, not a constant volume system.

SeaRat

You sir are right on target. I was going to post a pic or 2 of mine but there didn't seem to be much interest in the thread. Mine is also missing the regulator. I dove mine with a dry suit and a regular BC inflator. It of course it didn't work as designed but worked well enough to dive with for awhile. Yes it was ahead of it's time, probably part of the reason it didn't catch on. The bulk of the unit didn't help it either, with a tank and weight in the comparment it was a fairly heavy unit. A lot better suited for boat diving than rock hops.

 

[John C. Ratliff]

AfterDark,

I have used the Dacor Nautilus CVS without the regulator too. That was the original one that I got a few years back. I made the following photos of it with vintage gear--a Sportsways Hydro Twin balanced two-stage double hose regulator, with Healthways mouthpiece and Nemrod Snark III hoses:

This is how high the unit rides in the water with twelve pounds in the weight chamber.

This photo shows how high I can be out of the water with the unit at full buoyancy; my double hose regulator doesn't free flow much (have to really work at it even on your back).

This is about as good a photo as I have for how the unit looks while wearing it.

Using it without the regulator can be done, but I needed to be careful to continually add air while going deeper. It is a pressure vessel, and could implode if no air was added at depth, which is the main reason why Dacor wanted to have each person undergo specialized training before using it. I got the unit with a regulator because without it the unit could be unsafe in hands which don't understand it.

I dove the unit about two weeks ago, and thoroughly enjoyed the dive. And, I am a rock hopper. I don't dive from a boat, although I have thought about having the Nautilus CVS scuba be towed behind my canoe at one of the Oregon lakes, then getting into the water and donning it. I didn't got around to that this year, so that is on next year's agenda.

John

 

[Mr.X]

Very cool photos. The whole package looks almost like a techy-rebreather. I like your Weineramers.


X

 

[John C. Ratliff]

Mr. X,

The Weineramers were not mine, but the nice fellow who was at the river in a kayak and took my photo with my Nikonos II. Unfortunately, the Nikonos II flooded a bit that dive (it's getting pretty old) but I was able to salvage the photos.

SeaRat

 

[SwimJim]

You ought to have that Nikonos serviced John. Those are nice units. I still have one although I haven't used it in about three years since going digital. Theres a place in Monterey California that I used to send mine for service. Can't remember the name off hand, but they were very good and stood behind their work. I'll look it up if your interested.

Jim