Homebuilt ROVs Forum

How about using PVC floats with foam inside? Or even using something like Great Stuff. A person could fill a 8' section of PVC with Great Stuff, let it cure, then cut the sections to appropriate lengths and cap the ends. This way, if any water did find it's way in, it hopefully wouldn't completely compromise the float. Just a thought.

bigbellydude wrote:Has anyone ever considered using Styrofoam as a buoyant? I would think that it wouldn't compress at further depths because of its rigidity. I don't have any experience with this yet, but my MATE team is considering using it for our floats.

We used to send Styrofoam cups at depth with the industrial ROV's during sea trials, they would come back to the surface all still perfectly shaped but ... tiny! More than 50% size reduction, and I don't recall testing at more than 600 feet.

PaulC wrote:Has anyone thought of using either regular or synthetic cork for tether floats? It doesn't compress very much, and can be drilled.

I have acquired a carton of wine cork for that purpose, but my "sea trial" is not for a few months... My intent is to shape them, to minimize the entanglements spoken about by previous posters, and drill them through. Only one "line" of my umbilical will run through the cork, as my umbilical is of the "twisted" type (poly rope loosely twisted around one coax, 5 #18AWG's, and a small three conductor #24AWG flat cable).

As a plan B, I want to try strips of bubble wrap material, I tried to compress the small bubbles by hand on top of a scale, and they averaged a burst pressure (very uneven, as opposed to depth pressure) of 14 lbs. Per bubble. Very flexible, cheap as dirt. But fragile. Like I said, plan B.

Hey SoakedinVancouver, If I was going down the path of using styrofoam, which I have in the past I used the blue construction foam instead of the white pelletized kind. It's not nearly as fragile.

PaulC, thanks for the new Plan B!

This forum post may have been lost a while ago but if you do decide to go with the idea (good luck with it) you may be interested in using the floats found inside toilets. They are cheap, about £0.50, and they are ready shaped e.t.c.

All you would need to do is drill a hole in both sides and thread the wire in, you could then fill it with expanding foam e.t.c. or seal the ends properly.

I know I am reviving an old thread however I thought this might provide some inspiration for some of the ROV builders out there.

Solid foam floats such as the mini foam footballs shown below might work as tether floats although im shure with time they would need replacing eventually their shape would almost eliminate tether tangle.

Alternatively a hole could be drilled through tennis balls the tether fed through and then the balls filled with expanding foam. although experimentation is needed to get the correct distances between tether balls amongst other things.

Again, reviving an old thread but I found some rope outer layer stuff (can't remember the name) which floats, I found mine in one of those smaller hardware type stores which sell all those odd pipe connectors that you can't find in the big shops.
Shall try and find it again and update this.

http://www.uline.com/BL_3912/Polypropylene-Rope

This maybe?

Manhattan would you use the rope in the link as part of the tether (inter twine the rope and tether) or cut pieces of the rope and add them to your tether?