Trim Issues?!!? HELP!!!!!

[BB1]

Hi All,

I thought I'd chuck this out to the SB community and see if I can get any good advice.

I have a recently aquired Whites Fusion with the Tech LE skin and use 4th Element arctics underneath and wetsuit booties due to my ginourmous feet - this is my first drysuit!

On January 1St I started my Deep Cavern Course and my very first drysuit dive (yes I know - task loaded!! )

First day was almost a complete bonafide disaster - learning curve so steep I needed climbing gear.

My problem is trim..................

Having done a buoyancy check in the pool before I went down I had a rough idea of weight needed - it was off for the fresh water we were diving in.

With a stainless plate, doubles, manifold etc, as soon as I completely stopped moving I would nose dive straight into the bottom - hello silt!!

Changing to my Kydex plate (OMFG how thankful was I for remembering to take that!) helped ease the situation a little but not enough.

As soon as I got slightly head down at all my calves and feet fill with air and chaos ensued........ :crying2: Only 1 feet first ascent from 20ft but plenty of uncomfortable moments especially difficult during skills training.

Onsite brains trust decided I needed to get weight down by ankles - I'm 6'4" so a very long lever and a bit of a floaty person with padding (not a bloater but I'm a big guy!). 2 x 1lb weights taped to each fin did the trick and settled things down a LOT. Not quite happy days but closer.

Turns out I also needed another 3lb's of weight on a belt for when my tanks got really low to counteract the gas shift in buoyancy. Would add that weight for dive number 2 of each session.

Our trainer (highly experienced, penetration/expedition cave diver) trained us to NOT use the wing for buoyancy unless carrying a stage/deco tank that made us heavier than suit inflation could cope with. He said add enough to remove squeeze and keep adding suit gas to maintain that volume while descending and be correctly neutrally weighted to start with.

At the end of 10 days I had done 40 drysuit dives and passed my cave cert as we just carried on diving and did our pre-requisits for cave and continued training. I felt a lot more comfortable by the end of the 10 days but still had to be very concious of not getting air into my legs which is easier said than done!!!

What is my best course of action from here???

Proper ankle weights?
A pair of gaitors? - Golem wraps.
Chuck Taylors/rock boots instead of neoprene booties?

Or do I just need to dive more and try again without the fin weights?? I'm really not confident that it'll improve much more as I have the suit fairly nailed down I think after so many dives in such a short period of time which accelerated the learning process.


Any insight appreciated!

 

[ScubaVideo]

Gaitors - Halcyon, they will be your best friend in a DS. I have naturally floaty legs and always used ankle weights with a WS, but so far seem fine in a DS with gaitors.

 

[*dave*]

Most minor trim issues can be compensated for with leverage and body positioning. What you are describing requires shifting some ballast, now that you've figured out how much you really need.

The ankle weights shouldn't be necessary, but the additional ballast they provide likely is. It's pretty far out on the lever and would likely make your feet sink, were it not for the excessive gas in your feet, which is countering the ballast. I've found wetsuit boots work well for me and also limit the rate of gas transfer to the feet, but support can be an issue.

After losing the ankle weights, I'd try moving to a 4# tail weight and possibly loosening the shoulder straps, while snugging the crotch strap to allow your rig to ride an inch or two lower. This is likely where most of your answer lies, but it takes tweaking the variables to get it just so....

The Fusion is a great suit, but if you are going to be diving with slung bottles, it would seem a wing would be better for controlling buoyancy. Offsetting gas to one side of the wing will compensate for the weight of the stage on the opposite side, which isn't possible using a DS for buoyancy(is it?).

 

[BB1]

Most minor trim issues can be compensated for with leverage and body positioning. What you are describing requires shifting some lead, now that you've figured out what you really need.

So I'm going to be stuck with Ankle weights??

 

[*dave*]

So I'm going to be stuck with Ankle weights??

Okay, I'm done editing.

 

[BB1]

Thanks heaps for the advice Dave.

I'll try the tail weight out and see how that works out.

I cant lower the tanks anymore, I already have them mounted in the lower holes on the plate and I cant drop them any further in the bands and still reach the valves - can only just reach them now. We tried all these things before resorting to the ankle weights. Thinking about it though, the crotch strap may be a little loose as I remember my rig feeling like it was moving around on me a little at times, I messed with it while fitting the Golem Gear butt plate for the deco tanks.

I have also tried extending my legs back more as well to increase the "lever" as well with little success.

I think you're right about when diving with stages, use very minimum air in suit and use wing more. When just using back gas then use suit only as its far easier to control in my limited experience so far.

Next test in about a weeks time!

 

[Jim Lapenta]

The by the book way is to use the suit for buoyancy. The reality for many DS divers, myself included, is just enough air to offset squeeze and then use the wing for buoyancy. As you progress however you will get your weighting better and see that properly weighted the air needed to offset squeeze is most times enough to control buoyancy as well. I'm kind of starting over as I sold my old DS that I had over 120 dives in and have a new HOG Predator suit. It fits a little different (better than my old one) and having a new undergarment -Pinnacle merino evolution, there is some adjusting going on. the learning curve is no where near as steep. That said I have been using the dive rite gaiters from the beginning. Not only do they aid in reducing air migration to the feet but also streamline any excess material that may be present.

An added but not touted benefit for me as well is the extra support they give my calfs. I'm on my feet on a concrete floor all day, 5 days a week, 10 hours a day. Tried mats, shoes, etc and my calfs still ache at times. Except after diving dry. The compression of the gaiters seems to really help.

Your point about task loading should be heeded as well. A little time to practice with the suit just diving dry might havew gotten you in the habit of using both inflators to compliment each other. It is not hard. Many OW classes are taught in dry suits.

 

[HenrikBP]

I'll try the tail weight out and see how that works out.

I cant lower the tanks anymore, I already have them mounted in the lower holes on the plate and I cant drop them any further in the bands and still reach the valves - can only just reach them now.

What fins are you using? Some of the heavier rubber fins (Jets, Turtles, Rocket, Hollis F1) can help with head heavy trim.

What tanks are you using? AL80 go "tail light" when empty.

Tail weight is a good option.

If you have the tanks in the lowest holes on your plate you also have the plate in the highest position it can be. Less of an issue with your Kydex plate, but every little thing counts. You could try moving the tanks to the highest holes and then lower the whole assembly by loosening your shoulder straps. You'd end up with the valves in the same position, but with the overall "ballast" lower on your body.

Henrik

 

[tasdiver]

I also dive a white's fusion drysuit with neoprene booties. I found that using "fin keepers" over the "sock" portion of the drysuit (under the booties) helps keep the air out of my feet. It took a bit of getting used to as I was diving a DUI with rock boots, but I'm really happy with the result.

 

[Kern]

If you're using twin 12 x 232 tanks & using your DS for buoyancy, the gas bubble will be far to large to control effectively. Using the wing for buoyancy may also allow you to put some lift where it will assist in preventing nose dives.

You should be correctly weighted for every dive just in case of a worst case scenario, complete loss of back gas, not, "Oh, I'v used up some gas, I'd better add some weight for the next dive".

As a guess, I'd say your main problem is too much gas in the DS, & your lack of experience using doubles.

Ankle/fin weights are a lazy, down & dirty way to fix the problem. Experience, correct amount of gas in the DS, correct weighting & a weight belt/tail weight are far better long term solutions.

PS. What grommet holes on your wing are you using to mount it to the BP?