Dry Suit Zipper Configuration

[billseamon]

Hi all,

I was at the Long Beach Scuba show this weekend. Talked to the Posiden rep about dry suits and the different configurations. Some of his comments were interesting and was wondering if they are true. Below are his obervations.

1) On self entry dry suits, the zippers don't last as long because bending at the waist causes strain on the zippers and they fail faster. The zipper across the shoulder doesn't get bent as much and last longer.

2) DUI style zippers require the torso to be made longer so you can get the shoulder over your head, so they need the strap to gather up the suit at the croch. This adds cost to the suit.

3) Neopreme seals don't seal as well as latex seals.

What does everybody think?

 

[SubMariner]

Hi all,

I was at the Long Beach Scuba show this weekend. Talked to the Posiden rep about dry suits and the different configurations. Some of his comments were interesting and was wondering if they are true. Below are his obervations.

1) On self entry dry suits, the zippers don't last as long because bending at the waist causes strain on the zippers and they fail faster. The zipper across the shoulder doesn't get bent as much and last longer.

2) DUI style zippers require the torso to be made longer so you can get the shoulder over your head, so they need the strap to gather up the suit at the croch. This adds cost to the suit.

3) Neopreme seals don't seal as well as latex seals.

What does everybody think?

Frankly, I think that was one company's rep bashing a competitor.

1) Pearce has a DUI CF200 crushed neoprene self-donning drysuit that is probably 15 years old. He basically stopped using it because of the dreaded "winter shrinkage" that hasn't quite diminished. . There was never a problem with the zipper. AAMOF, he's had a DUI 350TLS trilam for about 5 years (as have I). Again, self donning. No problems.

Meanwhile, we have several friends who have self-donning suits by other mfgs like Abyss. They don't seem to have any problems.

That being said, regardless of the type of zipper on the drysuit, if you don't maintain it, it will fail. Simple as that.

2) If a strap @ the crotch "adds cost to the suit", it's negligible. The single most expensive part of ANY drysuit is the zipper. #2 are the valves.

3) There are pros & cons to latex seals. There are pros & cons to neoprene seals. In the end it's pretty much personal preference.

 

[JeffG]

1) On self entry dry suits, the zippers don't last as long because bending at the waist causes strain on the zippers and they fail faster. The zipper across the shoulder doesn't get bent as much and last longer.

I have seen some body types/zipper (self-entry) configs that would say "truth" to the above....But it may have more to do with fit...(ie buy a drysuit were the person is at the max of the recommended height) because I have seen lots that do not have any stress on the zipper (self-entry)

2) DUI style zippers require the torso to be made longer so you can get the shoulder over your head, so they need the strap to gather up the suit at the croch. This adds cost to the suit.

Backwards....The torso was made "longer" to help the diver put it on ergo the zipper had to change...and you don't buy DUI suits to save money

3) Neopreme seals don't seal as well as latex seals.

I believe this to be true...It was for me....(I have never heard of anyone that says they leak with latex, but seal with neoprene)

 

[zf2nt]

Hi all,

I was at the Long Beach Scuba show this weekend. Talked to the Posiden rep about dry suits and the different configurations. Some of his comments were interesting and was wondering if they are true. Below are his obervations.

1) On self entry dry suits, the zippers don't last as long because bending at the waist causes strain on the zippers and they fail faster. The zipper across the shoulder doesn't get bent as much and last longer.

2) DUI style zippers require the torso to be made longer so you can get the shoulder over your head, so they need the strap to gather up the suit at the croch. This adds cost to the suit.

3) Neopreme seals don't seal as well as latex seals.

What does everybody think?

Just within the DUI product line, you can easily see the extra cost that goes with the self-donning configuration:
(a) The self-don zipper is much longer than the shoulder entry zipper.
(b) Because the self-don zipper is exposed to abrasion, it has to have a protective sheath with a secondary zipper to close it in order to keep the main zipper from being damaged. In the shoulder entry configuration, the BC will protect the zipper so no protective sheath is needed.
(c) In the self-don configuration, the expanding torso is required in order to have room to get the neck seal up and over your head.
In addition, DUI has an extra compartment in the self-don versions around the neck seal so you can tuck your hood under it. This isn't present in the shoulder entry configuration.
Sort of to make the point on cost difference, I searched bay area dive stores and the best price on a CF200X I could locate was $1765. On the other hand, I haggled a bit and managed to get a CF200/SE for $1400. For $365, you can believe I'm willing to ask my buddy to zip me up!

Bruce

 

[MechDiver]

Backwards....The torso was made "longer" to help the diver put it on ergo the zipper had to change...and you don't buy DUI suits to save money

Diagonal zip front entry suits have to have additional material in the torso. This is a factor of the zipper location, not the other way around. My ATC zipper front entry has no additional material as its not needed to don the shoulder part. My diagonal zipper suit has the additional material.

This has nothing to do with brand, but the style of suit and zipper location.

Also, on the "bending at the waist" thing. How many times do you bend over far enough to harm the zipper once you have the suit on? Essentially a bogus point.

Neoprene seals suck.

MD

 

[JeffG]

Diagonal zip front entry suits have to have additional material in the torso. This is a factor of the zipper location, not the other way around.

billseamon asked about DUI suits...Quote from DUI's web site "The telescoping torso – the first truly self-donning drysuit".

So I will stick with my orginal quote "Backwards....The torso was made "longer" to help the diver put it on ergo the zipper had to change...and you don't buy DUI suits to save money "

What you said is probably true for the other manufacturers...but he asked about DUI

 

[Bob3]

Poseidon was the very first drysuit manufacturer to use the waterproof zippers (1963) They were actually the same zippers as the space suits used, and Poseidon's early suits had the "crotch zip" as used on most space suits yet today.
There are a few different designs of self-donning suits, with some the zippers can get strained during donning/doffing, shortening their life span.
The Poseidon rep was probably referring to the zipper used on the Unisuit.
Out of all the current different zipper designs, the "around the neck" style as used on the Poseidon Unisuit is probably the most zipper friendly. There's almost no way to strain the ends getting in & out and there aren't any load bearing straps riding on it.
With a bit of care & attention most designs should last at least as long as the suit though.
Bottom line is it mainly cooks down to personal preferance, but watch out for the short zippers that get stressed in the corners when detting into/out of the suit.

In general latex seals are considered to be more dry, unless you have small and/or tendons popping up on the wrists.

 

[mjh]

I have a neoprene neck seal and I am sending it back to have a latex put in. The second you have to crane your neck in any direction water comes in.

 

[Bob3]

I have a neoprene neck seal and I am sending it back to have a latex put in. The second you have to crane your neck in any direction water comes in.

I take it you have the neck seal tucked in pointing down towards your toes? (skin on skin)
It's a pretty simple matter to slice a wedge out of a neoprene neck seal & reglue.

 

[mjh]

Thanks for the Tip Bob3, I'm sure it's and easy fix but I'm sure I'd find a way to mess it up. Plus I want them to check for holes, maybe change my shoulder dump valve, etc... After 4yrs it's time for a check up.