My Cute Thruster Balls

[O C Diver]

Someone posted on a thread about making plugs to fit their bow thruster (sorry I couldn't find it to give you credit). I fabricated a set out of Coosa board and neoprene. While it did work to eliminate water flow and keep barnacle growth on the propellers to a minimum, I've had issues with them coming out unintentionally. Was preparing to rework the foam when I came across these cute thruster balls.



Polyform makes these (A0W), and Taylor also makes an equivalent size for my 8" tunnel. Obviously you can adjust the pressure to increase the size for a perfect fit. Installed them to day with high expectations. A 1/4" braided rope allows me to pull them out while standing on the deck.

Because I'm such an Eco friendly boater, I squint an ounce of bleach in the tunnel from a plastic syringe, before installing the second plug. I'm pretty sure I heard a baby barnacle scream, "NO".

Ted

 

[rgano]

I have not heard of plugging, I assume temporarily, a thruster tunnel before. I have only ever had a thruster on this lift-kept boat; so my experience is slight. Is this something you employ when moored for an extended period, and is getting in the water a requirement to install them? Enquiring mind wants to know.

 

[ScottC]

Hmmm...most of the world’s barnacles must reside on your side of the globe. When we lift out every year, I scrape the barnacles (all three or four of them) off my bow thruster blades with a pocket knife. Like rgano, I’ve never heard of thruster covers!

 

[Comodave]

Ted,

How do you keep them in the tunnel? Don’t they float out? Or do you use the line to secure them but then you must have to get in the water to do that???

 

[O C Diver]

I have not heard of plugging, I assume temporarily, a thruster tunnel before. I have only ever had a thruster on this lift-kept boat; so my experience is slight. Is this something you employ when moored for an extended period, and is getting in the water a requirement to install them? Enquiring mind wants to know.

Leave your boat in brackish to salt water at above 70 degrees F and the barnacles and other hard growth start growing. Above 80 degrees, it's like they're on steroids. The back sides of the propellers and the down leg are tough to clean without removing the propellers. Removing the boat from the water for a couple of days kills them, but the shell is still there. Barnacles on the propeller blades can dramatically reduce efficiency and cause vibration.

Yes, getting in the water is required to install them. I wouldn't do it unless the boat was going to sit for a couple of weeks.

Hmmm...most of the world’s barnacles must reside on your side of the globe. When we lift out every year, I scrape the barnacles (all three or four of them) off my bow thruster blades with a pocket knife. Like rgano, I’ve never heard of thruster covers!

It's definitely a warm water problem. The higher the nutrient content in the water, the faster they grow. July through September are prime barnacle months in Chesapeake Bay. From nothing to the size of a dime in a month!

Ted,

How do you keep them in the tunnel? Don’t they float out? Or do you use the line to secure them but then you must have to get in the water to do that???

The balls are expanded with inflation to reach a snug fit. It takes modest effort to push them in and pull them out. The eye with the line is facing out. It goes up to and through the bow hawse pipe and is tied off. While getting in the water is required for installation, I should be able to pull them out with the line. If not, there's a finger pier on the starboard side for a straight pull and bumping the bow thruster should expell the other side.

Ted

 

[Comodave]

I was just wondering.

 

[jleonard]

There used to be a home made pontoon/ houseboat on the Ct river named “Barnacle Balls” but it didn’t have a thruster

Maybe be a cousin?

 

[Wayfarer]

I feel a strong urge to remark about how you're holding those things, or to say something simple like 'Hey Ted, nice balls.'

But I don't think I will. Yeah, I'd better not. Family friendly forum and all that.

Good think I thought that through. Good job Dave.

 

[GFC]

'Hey Ted, nice balls.'

 

[O C Diver]

I feel a strong urge to remark about how you're holding those things, or to say something simple like 'Hey Ted, nice balls.'

But I don't think I will. Yeah, I'd better not. Family friendly forum and all that.

Good think I thought that through. Good job Dave.

New TF social distancing guidelines require 60' separation when admiring another member's balls.

Ted

 

[bayview]

Hmmm...most of the world’s barnacles must reside on your side of the globe. When we lift out every year, I scrape the barnacles (all three or four of them) off my bow thruster blades with a pocket knife. Like rgano, I’ve never heard of thruster covers!

FL west coast is the barnacle capitol of the world.

More barnacles here than I ever had in the US NE or west coast.

 

[Choices]

60' is not far enough for admiring balls of same sex...

 

[Shrew]

So, what happens when you're in an anchorage, a squall blows in and you start dragging? you fire up the main(s) and want to use the bow thruster because you're packed in a tight anchorage.

Now what????

 

[O C Diver]

So, what happens when you're in an anchorage, a squall blows in and you start dragging? you fire up the main(s) and want to use the bow thruster because you're packed in a tight anchorage.

Now what????

First, I expect to be able to pull them out standing on the deck. If they're to tight to do that, i may deflate them a little before inserting them the next time.

It's extremely unlikely I would ever insert them at anchor. As mentioned previously, if I anticipate moving within 2 weeks, I wouldn't put them in. To date, my longest stay at anchor has been 3 nights. For me to be in the same spot for more than 2 weeks, I would be on a commercial / municipal mooring.

Ted

 

[O C Diver]

So, an update to the plugs for my bow thruster tunnel. After about a month, had my "barnacle reduction specialist" scrup the boat bottom yesterday.

Pulling the balls out of the tunnel took a moderate tug (very happy with the required effort) standing on the bow deck. In the picture, one can see a significant contact area between the balls and the tunnel from the blue bottom paint. The inside tunnel part of the balls had a black slime coating that I believe came from the remnants of dead marine organisms. The diver said there was nothing growing in the tunnel, just the slime that wiped out easily. The outside of the balls were fouled, including some barnacles. Cleaned everything up and reinstalled the balls with an ounce of Clorox in the tunnel.







Very happy with the results!

Ted

 

[rgano]

Gotta love that "barnacle reduction" specialist moniker.