Fullsuit v. John Style

[eastbaydiver]

So, I'm starting to purchase all my own dive gear now and I'm at the point where renting doesn't work for me anymore. I'm looking at wetsuits now. What is the difference between John style suits and fullsuits? I get the actual physical difference of one being two pieces and the other being one. Which is better? Which is warmer? Which style is easier to don and doff? Which style will be more comfortable to use on days with multiple dives planned? Which style has better range of motion? etc. Pretty much any info about the two styles would be great.

I'm looking at xcel suits right now, because I think I might be able to get a significant discount, but those are fullsuits, not Johns. In all my classes (open, advanced and rescue) I used John type suits though, which leads me to believe that there must be some benefit to those.

Most of my diving will be in California. I'm thinking either 8 or 7 mm's. Thanks.

 

[Damselfish]

well, a farmer john automatically gives you a double layer of insulation on your core. But of course if you need that you can accomplish the same thing by using something like a hooded vest or core warmer with a fullsuit.

many years ago johns used to be the common choice and you didn't see fullsuits. neoprene has become more stretchy and flexible since then which makes fullsuits work a lot better than they would have in stiffer neoprene.

One of the biggest problems I see with a farmer john is that IMO neither piece is useful on it's own - if I am someplace I want 7mm on my torso and legs, I'd hardly want my arms uncovered, and the thing will scoop water like crazy. And If I needed that thick top I wouldn't want my legs bare!

 

[muddiver]

Neither will work alone is not true. I have used my step through top with out the farmer john and it wored just fine. It's just a shorty with sleeves.

I like the two peice because it doubles the insulation over your torso. I have been on a number of deep dives with experienced divers wearing thicker one peices, only to come up warm while they climb on to the boat shevering. I have seen this even in Hawaii.

With the one piece jumpsuit you give up thickness for ease of puting it on, sort of. All wet suits when damp or wet are difficult to put on and to take off if correctely sized.

The other advantage to the two peice (farmer john) isthat I have three different tops for different purposes. One is a special buit top with a turtle neck that work with the neck seal on my diving helmet (made by M&B Wet Suits in Long Beach). And like previousely mentioned I have a regular hood with a short bib and a hooded vest for really cold days before I had a dry suit.

Also you can strip a two peice down and hang out on deck in the sun to warm up without the wet neoprene on your upper body causing evaprative cooling. You can't do that in a jump suit, it would be hanging down under your feet or around your ankles.

My two peice is a 5 mil with titanium lining. As far as I can tell it is as warm as my old 7 mil. But for California water "the more neoprene the better!"

 

[eastbaydiver]

Thanks for the responses. I get that the John has two layers, but at the same time, isn't it the same? If you have a 7mm John or 7mm fullsuit, don't you have 7mm total covering your core? Either way isn't the amount of neoprene covering you the same?

My understanding of wetsuits might be what is throwing me off. I thought a 7mm John would have maybe 4mm of neoprene in the bib part, with 3mm of jacket on top of that to bring your core to 7mm total. Wouldn't one piece of 7mm thick fabric keep you warmer than 2 pieces that equal 7mms because the water can't get in between the two layers on the full suit?

 

[MagicChicken]

I currently have a 7/5mm semi-dry full suit and a hooded 7/5mm shortie. IMO, the shortie doesn't add much warmth since it doesn't trap water very well.

I would think that a farmer john + hooded vest would be better at restricting water flow... especially if the hooded vest is in fact a hooded longsleeve shortie.

My 2 PSI...

 

[Luis H]

Thanks for the responses. I get that the John has two layers, but at the same time, isn't it the same? If you have a 7mm John or 7mm fullsuit, don't you have 7mm total covering your core? Either way isn't the amount of neoprene covering you the same?

My understanding of wetsuits might be what is throwing me off. I thought a 7mm John would have maybe 4mm of neoprene in the bib part, with 3mm of jacket on top of that to bring your core to 7mm total. Wouldn't one piece of 7mm thick fabric keep you warmer than 2 pieces that equal 7mms because the water can't get in between the two layers on the full suit?

My 7mm farmer john and 7mm jacket adds up to 14mm around my torso.
The down side is that I need more lead to bring me to neutral buoyancy.

The advantage of a one piece is potentially less water leakage pass, but in either case the fit is by far the most important thing to reduce water flow.

To obtain 14 mm around your core with a one piece suit you have to wear a 7mm core warmer (basically a shorty with no arms) over your torso.


In many ways the choice is just a personal preference. I started diving almost 40 years ago when the only choice where two piece and I still prefer them.

I like the zipper up front so that I can open it if I am getting hot. Yes, I can use my top by itself and even then I can get hot if the water temperature is high enough. Normally I would use a thinner suit, but if I am traveling and am not sure what to expect, the two piece 7mm is the most flexible.

I have a couple of thin one piece suit, one rear entry and one front entry. I prefer the feel of the front entry (I don't like the neck seal on the rear entry), but taking it off by myself is barely doable (it would be impossible on a thicker suit).


Again it is mostly personal choice base on what is available, but taking into account that fit is the number one priority.

 

[muddiver]

Thanks for the responses. I get that the John has two layers, but at the same time, isn't it the same? If you have a 7mm John or 7mm fullsuit, don't you have 7mm total covering your core? Either way isn't the amount of neoprene covering you the same?

My understanding of wetsuits might be what is throwing me off. I thought a 7mm John would have maybe 4mm of neoprene in the bib part, with 3mm of jacket on top of that to bring your core to 7mm total. Wouldn't one piece of 7mm thick fabric keep you warmer than 2 pieces that equal 7mms because the water can't get in between the two layers on the full suit?

No, the bib portion and the legs are all one peice and will be the same thickness. Same with the top. So when you slide the top over the bottom, the overlap makes 14 mil. Add a vest (hooded or otherwise) and you increase that thickness.

I use the hooded vest because my 5 mil suit has been deep a number of time and I get comments like "wow, your suit sure looks like it's been compressed". Neoprene doesn't last forever, it eventually breaks down and you loose the bubbles in the neoprene which is where the thermal protection comes from.

Having a tight suit that doesn't slosh is also very important. Invest in either a dive skin to help the wet suit slide on, or make a large bottle of 50/50 mix of you favorite hair conditioner to slather yourself with before trying to pull your suit on. The furry lined neoprene also works really good if the suit is wet, doesn't help any if the suit is just damp.