Bottom Questions

[rwappleton]

We are having our bottom media blasted now. The boat has had no bottom maintenance for the last eight years so to no ones surprise we have a couple hundred blisters. There are also another 60 to 100 that were not repaired properly or not dried correctly so they need attention also. None appear to be in to the fiber glass to speak of mostly cosmetic.

The yard is recommending a barrier coat after the blisters are repaired. I would like to hear pros and cons on that.

Also what rate per hour is fair for blister repair? I am really good with a grinder and filler and I am almost sure I could do it in a week (but I don't want to).

As always we want to hear the good the bad and the ugly!!!!!

Thanks so much,

Russ and The Admiral
43DC#511

PS: The Admiral is sooooo hooked on our new toy she wants to get her Captains licence! Am I gonna look good sippin a cool one on the back deck!!!!! I love it!

 

[TopHattandTails]

Your gonna here advice on this from lots of folks. It's the proverbial dead horse topic... Blisters and Hatt's are like McDonald's and fries. You can't have one without the other. Most folks will tell you - leave them alone, there no big deal and usually purely cosmetic. However, if you're taking the bottom off and starting afresh (and have the cash to pay for the work), I'd have the bottom peeled, dryed out real good (including the required washes to dry the blisters out), repair, then put the barrier coat on, then the tell coat of bottom paint (1 coat), then your 2 coats of bottom paint. Rates in our area (Great Lakes) are $100 a linear foot without the blister repair. I've contemplated having the yard blast my bottom, and then DIY on the barrrier coat and paint, but the timing issues of when the paints flash is a pita and I would save about $350 - not worth it in my eyes.

Go for it - even if for cosmetic reasons!

 

[saltshaker]

Hard to say without seeing it but yes most of the time a blister repair isn't needed. However, If the bottom is blasted and the blisters are opened up, then you have to fix them and seal up the bottom. Complete bottom job runs around $300ft. Rates will vary based on location but that's about what you should expect for a complete job. What ever you do make sure you use a good ablative paint when finished, that way you'll never have paint build up again. Micron 66 would be my choice, but again that can vary based on location. When finished you'll have a more efficient boat. A smooth bottom will make a big difference.

 

[Boatsb]

Hard to say without seeing it but yes most of the time a blister repair isn't needed. However, If the bottom is blasted and the blisters are opened up, then you have to fix them and seal up the bottom. Complete bottom job runs around $300ft. Rates will vary based on location but that's about what you should expect for a complete job. What ever you do make sure you use a good ablative paint when finished, that way you'll never have paint build up again. Micron 66 would be my choice, but again that can vary based on location. When finished you'll have a more efficient boat. A smooth bottom will make a big difference.

If they open them you need to repair them as stated. Also do not rush to meet your schedule as the better you sry them the better the repair. There is always varied costs in different areas. Also sometimes cost is associated with condition. More work cost more. If the bottom is blasted clean you should have the best chance to get an accurate cost estimate.

 

[utspak]

My two cents is, if you are going to the expense of a total bottom job then I would do coppercoat instead of bottom paint. You will get a good ten years out of it before the next bottom paint.

Something else to check out. http://www.coppercoatusa.com/

Stuart

 

[rwappleton]

One more thing.......How wide is the boot stripe suppose to be? the PO had painted over it almost an inch with bottom paint. What I would like to do is go back to factory width and a 1/4" white stripe below and then bottom paint.

 

[TopHattandTails]

Before going back to OEM, take a look and see if the water line has changed on the boat. Like most of us, these old girls get a little heavier with time. You may want to bring the bottom coat up a bit... Just sayin'.

 

[BOATER BOB]

I finished up my bottom job and its a job took 3 months . But i tried to do a good job on fixing all 10 thousand blisters I used system 3 epoxy putty it took a 1.5 gal with three passes on the blisters and three sandings then i put a coat of west over the bottom and as it got tacky i put the first coat of Interlux 2000 so it bonds. Now you have up to 3months to put the other 6 coats of Interlux on then the three coats of bottom paint .Have Fun I did. I used Petit ultimite 60 bottom paint.

 

[Boatsb]

I finished up my bottom job and its a job took 3 months . But i tried to do a good job on fixing all 10 thousand blisters I used system 3 epoxy putty it took a 1.5 gal with three passes on the blisters and three sandings then i put a coat of west over the bottom and as it got tacky i put the first coat of Interlux 2000 so it bonds. Now you have up to 3months to put the other 6 coats of Interlux on then the three coats of bottom paint .Have Fun I did. I used Petit ultimite 60 bottom paint.

Recheck your declared schedule. Its best to recoat the interprotect when its still tacky but up yo 2talk weeks or so depending on weather. Epoxy blushes out chemicals thatneed to be removed before declaring plus you will need to sand to get soon toothed for the new stuff to adhere to.

It should be only a weeknod two from the time you start the coating until finished. The drying is the long time most often.

 

[rwappleton]

They are finished with the blasting and I do not have a time line to be done. Our estimated schedule for splash is mid March. (we doin lots of other stuff) I do want it done right I just do not want to find out too late I paid too much!

Now let me throw a curve in. Anyone Know a good supplier for exhaust hose? 8" and yes I am checking with Sam's on Monday! I buy everything I can from them.

 

[Glory]

It's a big job, I did my bottom about 6 years ago. repaired the blisters and 2 coats of epoxy two colors of bottom paint.

Pros, save a fist ful of money.

Cons, like most jobs on the boat over budget on time.

JM

 

[jim rosenthal]

DON'T peel the bottom. Blast it clean, let it dry THOROUGHLY- this takes weeks if not months- and then fill the blisters with VC Watertite or some similar fairing compound, and recoat the bottom with InterProtect or equivalent barrier coat. While it is tacky, roll on your bottom paint.

Blue Note's bottom was done thirteen or more years ago with this system and has held up very well. When (several years ago) she was at Slane Marine for her Cummins engines to be installed, they had the bottom cleaned up with soda or dry ice blasting, I forget which, and it was all holding up beautifully. They rolled on two or three more coats of IP and repainted her. She is still doing fine.

Very few boat bottoms need peeling. It raises the costs considerably and makes the project take a great deal longer than it needs to, depriving you of the use of your boat for even longer. It also can compromise the bottom structurally depending on who does it and how experienced and careful they are with your boat. Don't peel it. Save some money and just blast it, dry it, fair it and recoat it. That will serve you just fine, and your boat will love you for it.

 

[saltshaker]

What does the bottom look like now that she's been blasted? If you have a lot of open blisters, the longer you can dry them out the better. Talk to the yard and see what they recommend since they are the ones doing the job. You could drape the hull and put dehumidifiers under the boat to help the process. This is much more effective if indoors and/or on pavement or concrete. It's crucial that you get it dry and properly sealed up. Blisters on a Hatt typically aren't an issue if left alone. Once opened up they have to be properly repaired or you will end up with a problem.

 

[luckydave215]

I went through this same thing, soda blasting to remove a million coats of paint opened up a bunch of (otherwise tiny non-issue) blisters.
We ground them out, filled, barrier coated and painted. All the water in those blisters was confined to the blister itself, spot grinding ~1/16" deeper took care of them.
That was three or four years ago, at last haul not a single blister was found.
DON'T PEEL THE HULL, you'll regret it.

 

[bobk]

I wonder why all the advice to not peel a bottom.

I bought a brand new Albin in 1986 and applied Interprotect before putting the boat into service (yes the mold release was removed). I had many blisters after the first season as did many other Interprotect users. The advice at the time was to let them 'ripen' a few years and they eventually found their way through the veil layer. I had the bottom peeled just enough to remove all the veil layer, dried it out doors in MD over a winter and I faired and built the barrier back using Vinyl Ester resin. I sold that boat in 2006 when I bought the 48MY. No blisters. VE is harder to use than epoxy, but it sure is a better barrier and worth the effort. Sorry, I digress.

Bobk
1981 48MY
Chateau de Mer

 

[rwappleton]

The bottom was blasted with wet glass. As I stated earlier we are in no rush. Mid march was our earliest launch date. She is on concrete in Charleston so humidity should not be a problem until April or may.

There are maybe 200 that have been repaired that are holding up well. Maybe 60 that reblistered. Deepest is maybe 1/4" and 99% just gel coat. Another 200 new ones all very minor.

I have pictures I am going try to download to tonight for further review. I decided against peeling before we started and it seems to me the barrier process HAS to be done precisely.

 

[Vincentc]

About 25 years ago we removed blisters on a 43 Gulfstar. Some of the blisters were the size of half an orange. I used a sharp paring knife to carve out the blisters using a circular motion and got pretty good at it after a few hundred times. There was an impressive amount of water inside that smelled of vinegar.

Drying takes a while.

After the knife I used a large grinder sander. i applied a coat o epoxy the while the epoxy was still green, followed with filled epoxy in the depressions. i used the grinder sander to fair things then two coats of epoxy.

It was a big job, and I had more energy then. Not sure what I would do now, but I wold definitely hire some workers.

I would also tent the bottom and use some dehumidifiers. May be a month to let things dry out.

I recently had good result applying bottom paint to epoxy on the shafts that was not fully cured.

Regards

 

[jim rosenthal]

I can't speak to this problem on other makes of boats. I haven't owned any other fiberglass boats. But the leading authority on refits of older Hatteras yachts, no less, strongly recommended against peeling the bottom, and I followed his advice. And I've not been sorry. I am not familiar with the laminate schedule on Albins, and I would not presume to give advice on what to do with a blistered Albin.

 

[Boatsb]

I can't speak to this problem on other makes of boats. I haven't owned any other fiberglass boats. But the leading authority on refits of older Hatteras yachts, no less, strongly recommended against peeling the bottom, and I followed his advice. And I've not been sorry. I am not familiar with the laminate schedule on Albins, and I would not presume to give advice on what to do with a blistered Albin.

Jim I have seen both peeled and blasted Hatteras repaired beautifully and to be fair each one was done because that was the best method for the damage. Other boats have similar issued and I have repaired blisters on dozens of boats over the years. While I think peeling is extreme it is sometimes necessary to get to a stable base. Baths do not usually need such a radical method but sometimes they are just that badly blistered.


By the way interprotect is jot a bad product when used properly. Too many people do not get enough buildup because of thinning, sanding or other mistakes. Most coats of interprotect dry far thiner that you may expect. 6 coats is usually my minimum as it gets thinned here in Florida to make application easier.

 

[Glory]

I see several questions about drying out the bottom after the prep is complete. This is a troubling issue in the NE, shorter boating season so you don't want to do the job in MAY, and it's cold in most if the off season. To remedy this I tented the bottom , from the boot stripe down, and on weekends while I worked on the other things on my list I let a kerosene heater with a box fan moving the air around under the boat run. Each day i used a moisture meter on a spot marked on the bottom, same spot every time, and it seemed to help. Any space type heater should work fine if you are fighting below freezing temps. in a visit to the boat one night i found an icicle hanging down from on of ground out blisters. I ground the area further and could not find any additional moisture.

When grinding out a blister , I used a dremmel tool ( several dremmel tools on the thousands of blisters, several hundred on the port and thousands on the starboard side) you grind into the blister and the carbide blade has a rooster tail of foul water, once past the moisture the grinding delivers dust, and days later some grinding sites are wet again. After using the above heat I managed to get past this.

My orignal reason for tenting off the hull was to prevent rain from running down the hull into the the many grinding sites, it turned to even more helpful for the drying process. As I indacated in an above post this is a time consuming and messy project, not the kind your criusing or fishing buddies will rush to help with.


JM