Making normal ultralight arms more buoyant

Hi all, has anyone made their ULCS arms more buoyant? If so, what material/product did you use? I know you can buy ULCS buoyant arms, but ive already got a heap of regular arms

Cor

Hi Cor,

Do a search here. Many users have used closed cell foam blocks either glued or mounted to their strobe arms. I think it's called Divine-Cell or Divyn-Cell or something.

Cheers

James

Core Cell or Divinycell are both brand name closed cell foam products which share similar properties. They are both are very light and do not compress when subjected to the pressures of recreational diving. Because the closed cell foam weighs less than the water that it displaces, buoyancy, or lift is created.

I used surplus half inch Core Cell scraps from a local boat builder. For glue I used Devcon Two Ton Epoxy. Painting the final project is aesthetically pleasing but functionally optional.

The photo below shows the completed project using Ikelite arms. No strobe arm movement is compromized with core cell additions as shown with scissored arm.

i'd have imagined that that specialised foam is almost as expensive as the difference of the boyant arms ! it can't be cheap anyway.

They buoyant arms aren't nearly as buoyant - I have a set.

Cheers

James

Has anyone considered the amount of additional drag you're creating by adding foam (or anything else) to your rig? I find that even one strobe can make quite a difference swimming the camera setup, depending on water conditions.

Has anyone considered the amount of additional drag you're creating by adding foam (or anything else) to your rig? I find that even one strobe can make quite a difference swimming the camera setup, depending on water conditions.

Before the addition of Core Cell components, my rig weighed @ 4 pounds negative underwater. According to my calculations, the addition of the core cell brings the negative weight down to 13 ounces. A three pound (1350g) difference!

Typically I dive in little to no current conditions. I'm not sure how the system would perform in Cozumel. But for me, removing the excess forward ballast definitely improved by buoyancy skills.

Here's another solution, for what it's worth, though I have to say at the outset that I only used this a few times, then decided the improvement in buoyancy wasn't worth the extra drag. I do a lot of diving in strong currents, and minimizing drag is the highest priority.

I bought some PVC piping, about 2" diameter, plus caps. Cut the PVC pipe into lengths about the same as the tray and arm segments (minus balls), then glued the caps on with sealant - I think I've used both epoxy and some thread sealant I had.

The caps, naturally, have a bigger diameter than the pipe. It's easy to attach the PVC piping to the tray and arm segments with a couple of plastic ties. And just as easy to rip them off again for travel. The PVC pipe segments are happy to travel steerage, thrown into the bottom of the dive bag.

It did make the rig a bit more neutral, and it was certainly cheap. I think the total outlay for one tray piece (I could have used two here) and four arm segment pieces was about US$3.00. But , as mentioned above, in the end I decided that the buoyancy wasn't worth the extra drag, so I don't bother wish these anymore.

Frogfish

that solution was a very common one for uw video pro's. You could rig those pvc pipes to hold the uw video light battery and mount the lights on so you had a completely removeable lighting rig (in video it's the battery for the video lights that makes it heavy. I have never had to alter my camera housing, the fact that i dive with very little weight in the first place (normally less than 2 pounds) the camera ifit is negative helps me at the end of the dive .......... and breath out ... I actually once saw a device made for ikelite housings that was originally designed to help seal them as people comlained they leaked, This device was on that you could plug your inflator hose (or something) to and it would pressurise your system from the inside, I guess it would also make it more bouyant. The only thing is you are introducing another hole or way for water to get into your system as well.

I forget who i did this with, but once I had a setup whereby there was a bottle tied to it that you could fill up at depth, it was a test idea, the full idea was going to be like a mini lift bag, but probably more like a blood pressure arm wrap device wrapped around the strobes or something ... doesn't really add to drag as it is just part of the strobe .. and can add bouyanc from the top .. which is where you want it from.