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Mtrewyn
11-17-2007, 23:09
This may seem like a dumb question but when the ad says "7mm john/jane" does that mean that the bottoms are 7mm and the top is 7mm, or does that mean that the bottoms are 3.5mm and top is 3.5mm,

I ask 'cuz a one jump suit is the same cost as a john/jane and if both top and bottom are 7mm than it seems to me that the two piece would be alot warmer and more versatile.

Any thoughts? I'm looking for one.

I have a 3mm now and my local dive sights in the middle of summer have a 50-60 deg temp below the thermalcline, and I would like to explore down that far, but with a 3mm well...too cold for me.

Damselfish
11-17-2007, 23:38
it means the top and bottom are each 7mm, and you have double thickness on your core. (And possibly feel like the Michelin tire man. ;) )

As far more versatile, I don't know. I never considered either piece of a 7mm farmer john to be something I would wear much on it's own. You could wear a 7mm jumpsuit on it's own, and layer a shorty or hooded vest if needed, both of which are pieces with more versatility.

Mtrewyn
11-18-2007, 12:40
thanks for the help!

I thought that was what it was, but I've seen some things that lead me to believe me the other way.

do you think layering is really worth the effort? Or you just back to the Michelin man syndrome?

Damselfish
11-18-2007, 16:35
Layering works, lots of people do it. It's layering whether it's a farmer john or a fullsuit and vest, just a matter of which pieces give you more versatility, whats comfortable and works for you.

quasimoto
11-18-2007, 17:36
I have a 3mm John and love it. I can wear it as a shorty or a sleeveless suit. I don't know that a 7mm would be that versatile but it would depend upon where you dive.

Damselfish
11-18-2007, 21:23
I have a 3mm John and love it. I can wear it as a shorty or a sleeveless suit. I don't know that a 7mm would be that versatile but it would depend upon where you dive.

with 7mm, well, where would you wear something with 7mm thick long sleeves and not want something on your legs? Where would you wear something sleeveless while wanting 7mm on your legs? (Actually, I have worn one or the other over a lycra skin of all things, cause it's what I had at the time, but that was far from ideal for anything!)

cow109
11-21-2007, 20:51
Farmer John never made any sense to me. I bought one for my first suit (because it was used, cheap, and in good condition, and it fit). But after one dive I retired it and spent $300 for a jumpsuit with hooded shorty that goes over the top. Much happier!

quasimoto
11-22-2007, 18:07
Farmer John never made any sense to me. I bought one for my first suit (because it was used, cheap, and in good condition, and it fit). But after one dive I retired it and spent $300 for a jumpsuit with hooded shorty that goes over the top. Much happier!

A lot of farmer johns are designed that way, or close to, minus the hood.

navyhmc
11-23-2007, 09:54
I have my first one piece after 30+ in farmer johns. For the colder dives, I still like the john especially when entering the water. It takes a bit longer for the really cold water to seep into your chest/back area dn then it's warmed a little. 'course puttng warm water in the suit first helps.

The one advantage I have noted already for the one piece is it takes a lot less weight to get neutral. That pays to reand though when you consider that a one piece has about 35%-40% less neoprene in it.

mcc2318
11-26-2007, 15:19
whats the point of the farmer john

nathanbarlow
11-30-2007, 06:56
whats the point of the farmer john

i think it is a design from military/commercial diving in th 80's - i know for a fact that british navy divers had that style in the 70's as my uncle was a navy man and has tons of photos of divers wearing farmer johns. I think the idea was doing strenous exercise underwater often means the diver needs to cool down - can take off the jacket part and just have the long john . . then can put it back on if needed . .

mpd525
11-30-2007, 10:02
the one problem i see with the john's, it looks like you stand a better chance of water flow through in it, and beacuse of that you never get the water warmed up.

Ber Rabbit
11-30-2007, 10:51
the one problem i see with the john's, it looks like you stand a better chance of water flow through in it, and beacuse of that you never get the water warmed up.

How much time have you spent diving in one? Any suit that fits is going to limit the water flow. I have two 1/4 inch farmer johns, from back before they used mm to describe thickness, that fit like a glove and once the water is in it stays in.

A 7mm farmer john can give you the Michelin man feeling sure, but if you can only afford one suit and want to dive in different temperature ranges a farmer john is flexible. Personally I prefer to have my students buy a 5mm farmer john, they are warm but not quite as restrictive. You can wear the top in the tropics if you don't have a 3mm, just unzip it to let water flow freely through the suit if you're too warm.

I have a 5mm one piece Henderson Gold Core that I froze in when we dove the Florida springs and that water isn't even cold. I find the same water temp to be comfortable in my farmer john even though it's probably compressed to 4mm or so over the years.

I just bought a 3mm farmer john that was supposed to be for the pool but it's too nice to sacrifice to the chlorine :smiley2: Looks like I'll continue to dive the pool in a 3mm full length suit with a 3mm shorty over it and relegate my new purchase to warm water trip status.
Ber