Move blocking for bottom painting

b_arrington

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Feb 21, 2007
3,469
Setauket, NY
Boat Info
Back Cove 37
AB Ventus 9VL
Engines
Cummins QSC 8.3 600
I'm going to have my bottom stripped (blasted) and then apply an epoxy barrier coat before new antifouling. The blasting service doesn't touch the blocking, so I'll have patches where I will have to move the blocking and sand of the last bits and paint the bottom.

My question is this - what's a recommended procedure to move the blocking so I can sand / paint? The blocking used by the boat yard is cinderblocks with wood cushions, pipe boat stands are not used. My configuration is 2 at the stern edges, 1 mid keel, and 3 in a transverse line forward (port, starboard, and center).

Here are pics of the blocking. Thanks for any advice.
IMG_5981.JPG IMG_5985.JPG IMG_5984 (1).JPG
 
Are you allowed to move the blocking yourself?

Question... why barrier coat? That's an unneeded expense for your gelcoat. For years before your hull, the composition of the gelcoat that SR uses has been pretty much impervious to blisters.
 
My boat yard is very flexible. The only work customers can't do is apply antifouling paint. Except for that, customers can do anything they want - engine work, canvas, sanding, fiberglass work, winterizing, covering the boat, whatever. Any vendor brought in just needs a certificate of insurance.

I planned to apply the barrier coat as an form of insurance to prevent any issues. I don't have any blistering issues that I know of, but I'm sure there is no barrier coat on there now. I figured that since I was going to the effort (and expense) of having the bottom blasted this would be the time to add a barrier coat. Not that I relish the thought of painting the bottom....

Is the SR gelcoat really that resistant to blistering that it's not worth the barrier coat? I'll admit I don't see this issue come up here much at all.

Anyway, I'll still need to move the blocking to remove the patches left over after the blasting is done so any advice on the blocking appreciated.
 
I'm sure for a small fee, the yard would be willing to move the blocking for you. Heck all the yards around here insist that they be the only ones to do so.
 
Certainly, it's your choice if you want to add the barrier coat - and of course it's not a "bad" idea - but with the track record of Sea Ray's gelcoat, I really think you're wasting money. Like you said, you don't notice any know and it's 12 years old...

So... the boat isn't so big that you couldn't use some jacks to lift it and move the blocking. But it looks like you're not on hardtop so you really should be using soem 3/4" plywood under the jack.

But, I agree with Bob that it really might be easiest/safest (and not all that expensive) to have the marina move it for you. Or... don't even worry about those spots - get 'em next time.

If you decide to do it yourself, see if your marina has a set of Yardarms that you could rent. Those would make it SUPER easy.
 
No steel stands?

Usually they are angled to prevent tipping and I wouldn’t have it any other way.

Wood blocking along the keel is the norm with 6 stands along the chines.

I bought my own stands a few years ago. A bit of a pain in the ass to haul and store, but at least I know their condition is consistent year to year.

Some of the loaners I see are pretty rough.
 
Like Laze Daze said the gelcoat will certainly be fine. However on my 260DA I had a lot of problems with the bottom paint flaking off. I had the boat bottom scrapped and sanded and had a two coats of Interprotect 2000e. Never had a problem with my bottom paint again.

My 340SDA had it's hull blasted and had four coats (probably excessive) of Interprotect applied followed by Micron Extra. The paint wore evenly and had no issues at all. It was a grey primer followed by a black paint. After last seasons power wash I could easily see it was time to repaint.

Based on my experiences - If I were to spend all the money to have the bottom blasted and painted I would spend the extra on the Interprotect Primer.

-Kevin
 
A 270 Amberjack can be lifted with a Marina Bull or similar forklift with ease. Why not just lift and blast? Or lift and move the blocks enough to get the spots you miss.
 
Looks to be a lot of weight on that single front block. Is there any support ahead of it? I would pay them to move it and maybe add a bit more in the front. Unless reinforced, cinder blocks give no warning before they fail.
 
Nothing to do with bottom coating. Rule of thumb is one keel block per 10 feet of boat. There is a lot of weight at the two contact points on your keel.
 
I am surprised they use cinder blocks. I would never allow my boat to be on them. Our marina uses only heavy wood blocking.
Every boat in my yard is on cinder blocks with a wood topper. Except for some of the larger sail boats that have their own cradle.
 
No steel stands?

Usually they are angled to prevent tipping and I wouldn’t have it any other way.

Wood blocking along the keel is the norm with 6 stands along the chines.

I bought my own stands a few years ago. A bit of a pain in the ass to haul and store, but at least I know their condition is consistent year to year.

Some of the loaners I see are pretty rough.

My yard doesn't use steel stands for power boats. On the bow they use piece of wood across 3 sets of blocks, and have adjustable angled stabilizers that are attached to the wood.
 
Looks to be a lot of weight on that single front block. Is there any support ahead of it? I would pay them to move it and maybe add a bit more in the front. Unless reinforced, cinder blocks give no warning before they fail.

I think its an optical illusion of the angle of the photo. It's pretty far forward. Also the weight is spread out across the sets of blocks on either side.
 
Nothing to do with bottom coating. Rule of thumb is one keel block per 10 feet of boat. There is a lot of weight at the two contact points on your keel.

I didn't know that rule of thumb, but I'm pretty sure my boat is blocked to that standard. It's supported at 3 points, bow, middle, and stern. The photos don't show it well, but the the stern support is quite wide on either side, about 24"x12" per side.
 
While I'm quite happy with the boat yard I use and have zero desire to move, I think folks' suggestions to use the yard's lift, fork lift, or marina bull are dramatically overestimating the yard's capabilities.

The yard is small - less than 1 acre - and scrappy. They have no marina bull, and one small fork lift that would primarily be used as an engine hoist - not nearly large enough to lift a boat. To pull boats from the water they use a custom trailer that's moved around with a surplus aircraft tug (cool little toy).

The yard is run by 2 guys, including the owner that sold his primary business and bought the yard from the former owner to be sure he had a place to put his own boat (and make sure the yard was open for others). He does much of the work himself, but also travels extensively. He doesn't make much of any money on the operation but that's fine with him. The owner delivers what he promises and when he promises it and at a very reasonable cost. There simply are not many marinas around me, and certainly not ones as reliable or as liberal in their policies. I live in fear of the day he sells the yard, and there are definitely fewer boats on the water around here.

So that said, I'll talk to the guys at the yard about reblocking the boat when I need it.
 
Like Laze Daze said the gelcoat will certainly be fine. However on my 260DA I had a lot of problems with the bottom paint flaking off. I had the boat bottom scrapped and sanded and had a two coats of Interprotect 2000e. Never had a problem with my bottom paint again.

My 340SDA had it's hull blasted and had four coats (probably excessive) of Interprotect applied followed by Micron Extra. The paint wore evenly and had no issues at all. It was a grey primer followed by a black paint. After last seasons power wash I could easily see it was time to repaint.

Based on my experiences - If I were to spend all the money to have the bottom blasted and painted I would spend the extra on the Interprotect Primer.

-Kevin

Thanks, that's really good to know. I have similar problems with the ablative paint flaking off. There are large sections of flaking paint and the surface is now very rough. It wears unevenly too. Getting the bottom blasted is step 1 to more even paint. I think my yard uses Pettit Hydrocoat. It seems to work well for our local conditions (hard growth + slime).
 
When paint flakes off right to the gelcoat it is due to inadequate prep in that area. It's like any painting job whether marine, auto or around the house - the prep job is the key. If the gel wasn't properly etched (whether chemically or physically) then the bottom paint won't stick very well. You also may have a combination of hard and ablative paint, adding to the "chunky" look. Also looks like whoever has been painting it hasn't been too worried about making it nice - appears pretty sloppy. It's good you're "starting fresh".
 
When paint flakes off right to the gelcoat it is due to inadequate prep in that area. It's like any painting job whether marine, auto or around the house - the prep job is the key. If the gel wasn't properly etched (whether chemically or physically) then the bottom paint won't stick very well. You also may have a combination of hard and ablative paint, adding to the "chunky" look. Also looks like whoever has been painting it hasn't been too worried about making it nice - appears pretty sloppy. It's good you're "starting fresh".

I'm 100% sure my paint is all ablative. I'm the original owner and had it at the same yard the whole time.

Frankly I don't think they do much prep work before painting. The hull gets power washed at haul out and that's about it. I'll go in an knock off any remaining hard growth. Next layer of antifouling goes on in the spring without anything else. Since I can't apply my own antifouling there isn't much I can do. I'm pretty excited about starting fresh, as I think the "chunky" condition is affecting my speed.
 
After having a "chucky" bottom coat on my 260DA I was thrilled to have it scrapped and sanded - still not as good as a full blast. My 340SDA was blasted by the PO (who I knew) and it made the bottom look so nice.

One thing to keep in mind is that after the bottom is blasted; give the hull a good inspection for any possible gelcoat repairs before repainting.

-Kevin
 

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