Lifting/Supporting a Catalina 18 for Bottom Painting

Ajay73

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Jun 11, 2011
253
Catalina 1980 C27 Meinke Marina on Lake Erie
Just bought a 2003 Catalina 18 (C18). I will be docking the boat for the season and so need to bottom paint. How have others supported the boat above the bunks and keel bunk to paint those areas? My thoughts are to place sawhorses in front and behind the keel with the aft sawhorse spanning the width between the bunks (therefore spreading the load) and the forward sawhorse supporting essentially a point load. Is the hull strong/stiff enough to be supported as I suggest? My gut feel is that it should be no problem. Thanks for any advice you can give.
 
Nov 26, 2012
1,653
Hunter 34 Berkeley
The weight of the boat should be supported on the keel. In other words the keel should be resting on wood blocks. The stands under the hull just keep it from tipping over.
 
Jul 12, 2011
1,165
Leopard 40 Jupiter, Florida
Is the boat going to be stored on a trailer? If so, are you asking how to paint between the hull and the supporting bunk boards? I've painted boats like this by coming up with a spanning support across the beam of the boat, like heavy-duty saw horses, and 'rocking' the trailer on its jack to separate boat and trailer. First drop the tongue down all the way, and put supports under the stern. When you crank up the trailer tongue, the stern will be supported by your saw horse, and you can get a brush or roller between hull and bunk. There's not much weight for an 18-footer, and a couple of 2x4's six or seven feet long should support it. You really don't need much room to get between them. Obviously, don't rock the boat or get under it while it's balanced thus. Reverse the saw horse for the front.

Here's an image from the interweb that I just grabbed, for ease of discussion:
 
Mar 28, 2015
22
Catalina 18 273 Pine Beach NJ
AJ,this is a subject that I am all to familiar with. I go through this ritual every year with my 2 boats and quite a few others. I have accumulated a large supply of cement blocks,planking,and other blocking. Some of which always seem to migrate to other parts of the yard,but that is another story. I generally start by painting the whole bottom on the trailer. When that is completely dry I then place cement blocks in pairs at each corner of the transom,alternating them as I go up. I will then start jacking up the back of the boat just behind the keel until I get about 2 1/2 or so inches above the bunks. Then add a cross plank and wood blocking till I am firm against the bottom. Then I will let the jack down. I will repeat the same at the bow. I also will jam 2 2x4's midships (with rags at the top to protect the gelcoat) from under the rubrail to the ground,all the while checking after each step that the boat is stable before even attempting anything else. You can then paint under the bunks and keel. When the paint is completely dry you can let the boat down reversing the order in which you went up,bow down first and so on. For my main blocking I use standard cement blocks. I also have 4x4's,2x4's,and 1x4's cut to 16"long and wedges. I use a small roller,about 1 1/2" in diameter and about 6" long for all my bottom painting. And also be sure to use a wide block between the jack and the hull. I discovered early on that my bottom will flex too much for my liking,so I will only jack and block in structurally solid spots such as near the transom,forward near the bow or close to the keel. Sorry for being long winded. Above all,go slowly and be careful. I have been doing this for many years on many different boats without any problems whatsoever,but I am still very cautious. Anyway,this is all much simpler than it sounds. If you have any questions just ask. Good luck and have fun!!! Jeff
 
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Likes: Parsons

Ajay73

.
Jun 11, 2011
253
Catalina 1980 C27 Meinke Marina on Lake Erie
Thanks all for the comments. Parsons, I would transfer the weight off the the bunks as you suggest by first lowering the tongue, fitting the rear supports across the beam, then raising the tongue, fit the front support across the beam, then lower the tongue somewhat. My primary concern is when the boat is supported this way the hull is strong/stiff enough to hold the boat weight without flexing the hull.
 
Jul 12, 2011
1,165
Leopard 40 Jupiter, Florida
As @JA Toms River explained, much better than I, go slowly and examine the hull at each stage. Your hull is actually stronger than you think if the loads are slowly placed. Trailered boats are designed for more point loading. I've seen cracking generally from rapid or repeated stressing, like striking rocks or fatigue. The rags or padding are the point that I forgot - thanks JA!
 
Jul 20, 2018
14
Catalina Capri 18 Everett, WA
Thank you for starting the conversation. Will be doing the same thing with my Capri 18 in the Spring.
However, my plan was to set the 3 jacks under the trailer, two on the back and one on the tongue, lifting the boat about 6". Then place supports under the boat and lower the trailer underneath it.
It seems this would be safer than the "rocking" action of lowering the front, supporting the stern and then raising it up again. At least it would put less strain on the boat.
My first time, and given then number of places I have seen the above process recommended, I am worried I am missing something.
Also, my plan was to support the stern near the transom and the bow as near to the trailer roller as possible. However, I recently read somewhere that most of the weight should be on the keel. Is that correct?
My 18 is a wing keel and I thought the wings of the keel were not necessary structurally strong.
Any and all advice is appreciated.
Cheers,
Nate
 

Ajay73

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Jun 11, 2011
253
Catalina 1980 C27 Meinke Marina on Lake Erie
Nate, your approach seems pretty good to me. Raising the trailer 6 inches would be pretty easy with 3 jacks but I might have to do it in two stages with the bottle jacks I have. I don't think they have a 6 inch range. As far as supporting the keel you could place a couple 2x4's in two locations under the keel, paint what's accessible, then move those blocks and finish painting. I wouldn't think though that if the keel just hung free it would be a problem.
 
Last edited:
Jul 12, 2011
1,165
Leopard 40 Jupiter, Florida
I wouldn't think though that if the keel just hung free it would be a problem.
So when the boat is floating, the keel hangs free from the hull. :)
First of all, relax. Your hull is tougher than you are imagining. It's not an eggshell and can take some bending and moving. Don't shock-load any spots (don't drop it!). Widen the points where it is supported so there is not loading at a particular point. Give it a little padding (rags or foam) to not scratch the underlying gelcoat. Move slowly and listen for stress, as well as looking.
 
Jul 20, 2018
14
Catalina Capri 18 Everett, WA
Ajay73,
Does your 18 sit low in the water on the stern?
Browsing the web, it looks like this might be a trait of Catalinas in general, but then there are so few 18s out there it is hard to tell.
The water line on my stern, with the outboard on, is about 2 inches above where it should be. Also, the bow is about 2 inches out of the water, showing about that much bottom paint.
At first i didn't think about it too much because i was seeing references to Catalinas doing this. However, I recently found a little fresh water in my starboard locker, which I am afraid might be coming from the scupper fitting....which of course now has me paranoid that the back is heavy with water intrusion.
Cheers,
Nate
 

Ajay73

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Jun 11, 2011
253
Catalina 1980 C27 Meinke Marina on Lake Erie
Nate, I can't answer your question as I just bought the boat in late October and won't launch until next spring. Looking at my boat's transom though it doesn't show any waterline grime or dirty gelcoat above the bottom paint. But as I understand from the previous owner it has been out of the water, unused for several years.
 

Ajay73

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Jun 11, 2011
253
Catalina 1980 C27 Meinke Marina on Lake Erie
Nate, sorry for this very late response to your question about the C18 sitting lower in the water at the stern. Yes, mine does sit lower than the factory waterline. Even at the beam of the boat though the actual waterline is above where the factory has it set. Before launching this spring (just launched today) I raised my bottom paint up about two inches and covers a lot of the wide blue stripe near the waterline. Last season I had a lot of growth just above the waterline even at the bow. The factory waterline was just too low.