Trim in Doubles

[cfenton]

I have only been diving doubles for a month or two and I started with hp100s. I was really head heavy and so I moved my weight from a 8lb v weight to 8lbs on a belt. This helped some but as I breathed the gas down I was still standing on my head. I just tried hp130s yesterday and they shifted the weight back some but again as I breath it down I am still having trouble. I find that I am compendating by shifting my trim to a bit of a more verticle position.

My question is did everyone else have this problem when making the switch to doubles? I am thinking of taking by ss bp/w and using an aluminum moving the weight down south. Good idea? How common in 100s/130s?

Thanks in advance.

 

[Meng_Tze]

Difficult to say. My suggestion is to try all sorts of combinations in a controled environment (like a pool or something like that). People are all different and some have a lower center of gravity than others, some are more bouyant than others.

Obviously if you are head down, you would add weight on the lower side. If you are looking for a balanced rig, you could add more weight as part of the rig itself (heavier plate, v-weights). Bottom line is to make sure you are properly weighted at 6m with near empty tanks. Trim can also be influenced by the angle of your knees (further out, you lift the head area, contracted more, head tilts down, etc etc). You could also look at the position of the backplate itself.

Try out combinations. We all were there at some point, it is just a metter of finding the right combination for yourself.

Good luck!

 

[cool_hardware52]

I have only been diving doubles for a month or two and I started with hp100s. I was really head heavy and so I moved my weight from a 8lb v weight to 8lbs on a belt. This helped some but as I breathed the gas down I was still standing on my head. I just tried hp130s yesterday and they shifted the weight back some but again as I breath it down I am still having trouble. I find that I am compendating by shifting my trim to a bit of a more verticle position.

My question is did everyone else have this problem when making the switch to doubles? I am thinking of taking by ss bp/w and using an aluminum moving the weight down south. Good idea? How common in 100s/130s?

Thanks in advance.

This may be old news, but if you haven't tried these tricks maybe they will help. The first two cost nothing to try.

1. If your wing has multiple grommet holes, move it "up" the plate.
2. If your plate has multiple sets of holes at 11" centers move the tanks "down" the plate, just be sure you can still reach the valves. I assume you already have the upper band as high as possible.
3. "Tail weight" like a V weight, just all the mass is from the lower band bolt south.

BTW, I have heard, not experienced first hand, that PST E8-130's are "top heavy".

Good luck,


Tobin

 

[Spectre]

What do you have for fins? What happens when you extend your feet farther from your body and arch your back?

 

[cfenton]

I have Turtle fins which are much the same as Scubapro fins, only they fit size 13 feet in rock boots.

The first thing I tried was using the CG drill to trim out. Funny thing is that when I extend my legs it actually makes the problem worse. As a result I have been diving in a slightly verticle trim in order to keep the bubbles up high. Not the best solution. I think putting a v weight down south might be an option.

I am basically trying to figure out if going with an aluminum backplate is the way to go. I have the bands as high as they go and all the ditchable weight around my waist. I'm still a little top heavy. I am trying to figure out if anyone else needed to switch from steel to aluminum before I go and get one ordered.

The kicker is that my tech1 is in a month!

 

[JeffG]

I have Turtle fins which are much the same as Scubapro fins, only they fit size 13 feet in rock boots.

The first thing I tried was using the CG drill to trim out. Funny thing is that when I extend my legs it actually makes the problem worse. As a result I have been diving in a slightly verticle trim in order to keep the bubbles up high. Not the best solution. I think putting a v weight down south might be an option.

I am basically trying to figure out if going with an aluminum backplate is the way to go. I have the bands as high as they go and all the ditchable weight around my waist. I'm still a little top heavy. I am trying to figure out if anyone else needed to switch from steel to aluminum before I go and get one ordered.

The kicker is that my tech1 is in a month!

I went with an Alum BP with my 130's and yes it does help. But I found the "head-heavy" issue to be more of a comfort thing. It felt like I was failing over, but I wasn't and the resulting trim was that I had was not horizontal (but I thought I was). It drove me crazy, enough to try my Alum 80's and I found they were easier to dive. Now that I am used to the feeling of being horz I can go back and forth between my 130's and my 80's with no real issues.

 

[Tavi]

With my 130's I use an aluminum plate. With my 100's I use a 5lb SS plate. My trim is good with both. I tried a SS plate with my 130's once. My trim was head down.

 

[cfenton]

But I found the "head-heavy" issue to be more of a comfort thing. It felt like I was failing over, but I wasn't and the resulting trim was that I had was not horizontal (but I thought I was). It drove me crazy,

Thanks Jeff...I had wondered about this myself actually.

Thanks Tavi.

 

[Hoosier]

I don't need any weight with 119s. I am wearing AL BP, DS, and 400g thinsulate.
Actually, I think I am over weighted. LOL ~~

 

[Dan Gibson]

My buddy in one of the DIRF classes had too much weight up high. Once an Aluminum plate was used instead of the SS plate, much of his trim and buoyancy problems were fixed. Once he replaced the Pro14 light with a Helios 9, he was easily the most improved in the class. He was only using the 300 Polar fleece with a DUI 350 TLS. My ears still hurt from the yo-yoing I had to try and keep up with in the first 5 minutes in the water.

Ask Brandon (I think BCS on this list) what he saw in his ITC/IE with my buddy and what he typically sees in classes with the heavy steel tanks and ss plates. I'm sure MHK would love to comment on it as well.

I am trying to figure out if anyone else needed to switch from steel to aluminum before I go and get one ordered.