As a part of my first ever haul out, I had a friend say that this was way to much growth after just 1 year and might indicate something with the shaft needs maintenance. Thoughts?
40.5: Shaft growth
- Thread starter svAtargatis
- Start date
I haul my boat annually. When the COVID pandemic hit, the boat sat in the water for at least 12 weeks because the Governor of MD prohibited recreational boating. This is what my prop looked like - and it had been treated with barnacle barrier. The shaft looked the same.
Anti-fouling not withstanding, growth will accumulate quickly on props and shafts that are not run regularly. Thanks to our government they have outlawed all of the products that actually are reasonably effective. Of course, dirty props have worse performance and use more fuel which produces more pollution, but that's another story....
The cleanest running gear in the harbor is on the launch boats.
The cleanest running gear in the harbor is on the launch boats.
Everyother week the tides are right for me to take my runabout to work... and on Monday I notice that I have to bump up the rpm for the first 20 min by about 200 to make the same speed through the water... then it goes back to normal for the rest of the week. I am assuming I am shedding the weeks growth from my bottom paint for that first 20 min.
The fact that your barnacles are concentrated where they are in that photo tells me two things:
1. It doesn't appear that your shaft strut got any bottom paint love when the bottom was painted last - the hull pressure washed clean, but the shaft strut has hard growth all over it. Easy enough to fix when you repaint.
2. I've tried two methods to discourage growth on the running gear - bottom paint and zinc paint. Ablative seems to wear off too quickly - I mean, it IS running gear, so that makes sense. You could try the expensive treatments that require exacting prep or they fail - or they fail anyway (see Kappykaplan's post above), but I've had luck with the zinc paint. You can buy it in its "marine" form from Pettit (Pettit Prop Coat in spray or liquid paint $35-$109), or you can get virtually the same thing from home Depot (Rust Oleum Cold Galvanizing spray paint - $8). Its not magic - nothing on running gear is - but in the brackish water of the Chesapeake it seems to do a decent job, and other than a few lucky barnacles my running gear comes out looking like my ablative bottom paint when pressure washed at the end of the season. Unfortunately I wasn't there when I was hauled out so I don't have any photos, but it didn't look anything like kappykaplan's prop from Lusby - not far from me in Deale. Can't tell you why - maybe use? i dunno.
At any rate, the Rust Oleum Cold Galvanizing on my prop shaft and prop seem to work pretty well - especially for $8. I give it at least two coats after a good sand to rough everything up, and then some acetone to clean it. If you're in true salt water (we're technically in brackish) I can imagine you'd need regular bottom cleanings, so may not be of any help. Couldn't tell where you are from your post.
Good luck.
1. It doesn't appear that your shaft strut got any bottom paint love when the bottom was painted last - the hull pressure washed clean, but the shaft strut has hard growth all over it. Easy enough to fix when you repaint.
2. I've tried two methods to discourage growth on the running gear - bottom paint and zinc paint. Ablative seems to wear off too quickly - I mean, it IS running gear, so that makes sense. You could try the expensive treatments that require exacting prep or they fail - or they fail anyway (see Kappykaplan's post above), but I've had luck with the zinc paint. You can buy it in its "marine" form from Pettit (Pettit Prop Coat in spray or liquid paint $35-$109), or you can get virtually the same thing from home Depot (Rust Oleum Cold Galvanizing spray paint - $8). Its not magic - nothing on running gear is - but in the brackish water of the Chesapeake it seems to do a decent job, and other than a few lucky barnacles my running gear comes out looking like my ablative bottom paint when pressure washed at the end of the season. Unfortunately I wasn't there when I was hauled out so I don't have any photos, but it didn't look anything like kappykaplan's prop from Lusby - not far from me in Deale. Can't tell you why - maybe use? i dunno.
At any rate, the Rust Oleum Cold Galvanizing on my prop shaft and prop seem to work pretty well - especially for $8. I give it at least two coats after a good sand to rough everything up, and then some acetone to clean it. If you're in true salt water (we're technically in brackish) I can imagine you'd need regular bottom cleanings, so may not be of any help. Couldn't tell where you are from your post.
Good luck.
In 2020, the creek the boat is slipped on got warm sooner than usual. My boat was not the only one affected.
I have never used this product as a bottom paint but I have painted more than one trailer with it. It is good stuff. I have a trailer in my yard that I painted with this about 9 years ago and it is still rust free.
Next time I haul my boat, I may try a squirt or two on all my metal parts.
I use Rustoleum Cold Galvanizing on my prop and shaft as well - I'm in salt water and get no barnacles at all.