Trimming a WACP-2

I've just acquired and started experimenting with a WACP-2 for my Nikon Z6. I'm curious if anyone has any experience trimming one of these. They're super nose heavy and the shade open/close knob seems like it would preclude the use of float rings..... I've sent out a couple of emails in addition to this query and will be sure to update people with any new information. There doesn't seem to be a ton of information available about the WACP-2 yet.

The reviews say there is a built in "buoyancy" collar. It is normally buoyant due to the volume of the lens. You might try removing the collar and test.

In water, according to Nauticam it weights 0.27kg, that is less than WACP-1 weights ay 0.32kg in water. Have you actually tried it out in water because it seems that trim should be easy at only 0.27kg or 9.5oz. I have used Nauticam 50x250mm float arms with the WACP-1 and they worked quite well. I also like my system a bit negative so that I can put it down without it drifting away. I also use the dual strobe system with the two float arms outboard and the two ball arm sections connected to the housing. Same configuration in the photo with a Nauticam 180mm dome port.

When using the WACP-2 in the water, it was fairly nose heavy. I can use float arms to achieve neutral buoyancy without any problems, but I was asking about trim. To bring the nose up, I need to add floats to the front end of the WACP-2. The shape of the WACP-2, and the shade knob, makes adding floats a little less straightforward than the WACP1 or a macro port. I was hoping someone who might have played with a WACP-2 might have some suggestions.

45 minutes ago, Jason Gulley said:

When using the WACP-2 in the water, it was fairly nose heavy. I can use float arms to achieve neutral buoyancy without any problems, but I was asking about trim. To bring the nose up, I need to add floats to the front end of the WACP-2. The shape of the WACP-2, and the shade knob, makes adding floats a little less straightforward than the WACP1 or a macro port. I was hoping someone who might have played with a WACP-2 might have some suggestions.

Jason, maybe you could find a way of putting some small weights at the back of your system to achieve the balance? Tire/tyre balancing weights maybe?

Thanks, Tim. My preference is generally not to use weights to solve a trim issue when something is already negatively buoyant. I'd like to eliminate all other options first.

34 minutes ago, Jason Gulley said:

Thanks, Tim. My preference is generally not to use weights to solve a trim issue when something is already negatively buoyant. I'd like to eliminate all other options first.

The problem you will run up against is that whatever you use to provide buoyancy is going to be large and to fully counteract the 270gr underwater weight would need to have a volume of 270 cm3  to displace that amount of water.  So you need to attach something the same volume as a soft drink can to the front of the port to get the lift in the right place. 

Lead on the other hand is 13x denser than water so a small volume in the right place will balance out the lift - and that weight can counteracted in float arms, where you have an existing product that has attachment points sorted out. 

If you are determined to avoid adding weight you will be looking at making something along the lines of this system:  https://www.ikelite.com/products/trim-weight-system-for-dslr-mirrorless-housings

You could have a roughly H - shape plate cut in stainless steel and attach to the tripod screw holes under the housing and use the section under the port to attach a couple of floats.  I say roughly H shaped the arm under the port could be cut curved so you could tuck in the floats either side of the port for example.  You could have a piece laser cut from 3mm stainless plate if you drew up a pattern.

Why don't you use a Stix buoyancy collar?

You would need few modules so you can just accomodate it behind the focus gear moving the needed modules upside.

Just in case someone in the future has this same problem, I'm going to let everyone know how I trimmed out the WACP-2. As mentioned, it is pretty nose heavy, which is the total opposite of my experience with Nikon Z6 and a 230mm glass dome port. The guys at Nauticam told me that they just push their first float arm segments very far forward, to counteract the nose-heavy, and then pull back the second float arm segments behind the front element. I tried that today and it worked pretty well. I was a little disappointed that I didn't come up with that on my own.... and I'm not 100% happy yet, but I think a day at a local spring (whenever I get a break from shooting) will get it dialed the rest of the way in without having to do anything too creative.

I don't get why you did not put a buoyancy collar.

The WACP-2 has a collar built into it, but it is still pretty nose heavy. Its a bit like trying to fit the collar you suggested over a 230mm glass dome - with the additional issue of there being a knob that opens and closes the shades on the dome which is in the way.