Gelcoat Issue Mac 26M (is it a lemon?)

[Divecoz]

Thanks for the clearifacatin Andrey.
I too have the Pin Head Pops... Hundreds of them on the flat bottom and mostly contained to the middle 1/3 of that portion of the hull. I got them the first year the boat sat in the water ( fresh water ) for the entire season , and they seem........not to have increased in numbers. I have never used a barrried coat as such. I do use 4 coats of WAX... Anti Fouling Boat Wax 2 coats machine buffed with the Final coat or two being Speed Wax , hand buffed.
I seem to have No More issues..But I still have those...and maybe, I am needing to addressed them, before I coat and paint the hull. I will once we move, Repair the bottom (???) and seal with a barrier coat and apply a Newer Type of Speed Paint to the bottom the the boat.. The Boat will sit most of the time on a boat lift..

[Andrey-314]

Franky speaking I do not believe that blisters is just a cosmetic issue even I wish to believe so. Each blister pin is created by microscopic channel coming into laminate unfortunately - this is so called osmosis, nothing else. It cannot be allowed that acid containing in each blister will start to destroy the boat hull under the gelcoat and unfortunately it cause an expensive repair for me. It was decided to remove ALL gelcoat under the water line and apply epoxy barrier (1-1.5mm) over all underwater area followed by antifouling paint. As stated it will guarantee hull from blistering for at least 7-10 years.

[Divecoz]

Andrey , I will get back to you after I make a couple phone calls today.. IMHO Gel Coats .. at least on these boat is more for esthetics than anything..
Its a relatively cheap way to add color to a boat and end up with a mirror smooth finish.. If I am wrong on this thinking... No Doubt I will be corrected
As I said, I will call a couple of pros..maybe I am all wet? But Our Gel Coat is... porous and most everyone is now suggesting barrier coats on most ... if not all new boats.. Some New Boats... Come with it applied at the factory..

[Divecoz]

I'm backkkkkkkkkkkkk
I made ONE Call so far and my EAR ... is tired from listening... Here is what I have been told..so far....
Yes I have worked on Macgregors and they use "a the less expensive" Gel Coat.. ..... He was nice about it anyway..
For the next Half hour we / HE discussed differences in and of Gel Coat's (Must be a slow day ..) Could it ,does it, the less expensive gel coat, protect the fiberglass..or is it just for aesthetics? Yes it does Grrrrrrrr..... and if water is trapped it can cause issues. Less water trapped could mean fewer, less issues..
First wash the entire under side of the boat . Then Clean it! I thought we already washed it? No..No No Now you clean it with Toluene.. Do that twice..
Now get this electric planner made for STOP! DIY in my driveway! OK grab your die grinder.. I dont have one.. Use a darn battery drill then.. With a tiny drill bit open and remove every blister in your case pin head pop.. Clean again with Toluene and let it dry for 24 hours. Next you should sand the whole Bottom STOP IT! DIY In My Driveway! I really think you should sand the bottom.... and then just use Marine Tex like it was Bondo to just fill all those holes wait 24 hours and sand with 300 wet dry and then barrier coat from the boot stripe down.. Thank you.... its been a real #$%^&* joy talking with you again .
I wont even reiterate all the information he blessed me with on how they used to paint the Miami Vice Type Big $$ Go fast boats and several types of paint still being used and ... Proper Curing times.. hahahahaha He says we should by all means address these issues.. Yes it really is a DIY project, that anyone, could do in the driveway or even the yard.. Cost at most a Couple Hundred bucks ..
YT Richard

[iredrider1177]

geeesh!!! something else to fix! dam! starting to get a little frustrated with all these quality issues. had a couple spots on the deck that i had to repair the gelcoat cracked and fell off like an egg shell the gel coat wasnt even attached to the glass, took me 2 days to properly fix those, and i too have the blisters.

[Divecoz]

I just got off the phone again.... this time with my brother Mr. Perfection....Everything he does or builds is PERFECT!
We were talking about Gel Coat..again and he knows the guy I called and laughed ..
Anyway.. Gel Coat... You dont nick or chip Gel Coat by dropping a tennis ball on it....it dont happen and I have chipped mine in numerous places.. Cabin slide and cockpit seat edges.. He has a 30 + ft. Twin 315 HP Diesel Dive Boat.. a Shamrock... $150K + it didn't come with barrier coat either.. BUT.. his boat LIVES on the boat lift! When he's not using it thats where it sits Out of The Water.. Its another cost added and it wouold cost you about..$500 to $1000 to have it done at a Marina.. WOW! Don't get me started on the scam.. but applying barrier coat is cheap ( under $100 3 to 5 coats) and easy.. and doesnt require special tools or ability..No One Is Going To See It if you do have a drip or a run.
here's a link and well worth reading..http://www.westmarine.com/webapp/wcs/st ... rier-Coats
It Might Be A Little Overkill here and there buts we live in a CYA world..

geeesh!!! something else to fix! dam! starting to get a little frustrated with all these quality issues. had a couple spots on the deck that i had to repair the gelcoat cracked and fell off like an egg shell the gel coat wasnt even attached to the glass, took me 2 days to properly fix those, and i too have the blisters.

[trip01]

Just noticed the Gelcoat Blisters in the anchor well. Had a piece of carpet in there to protect the gelcoat from the anchor. Reckon that with the rain we had, fresh water sat in there on the wet carpet.

Have taken out the carpet, also had some carpet under the fuel tanks which has now been taken out as water lies on one side under fuel tank.

Hard to see photo, however here it is...


Kind Rgds
Dave
26m (lives on trailer)

[ALX357]

Have a lot of discussions with yacht architect last weekend. Actually looks like gelcoat quality is not a real reason of blisters. Water can penetrate to hull fiberglass from inside ballast tank causing osmosis blistering in outside gelcoat. Based on my observation all blisters are located in the ballast tanks/pipes areas. This is the whorst scenario - even re-gelcoating / barrier paining outside the hull will not help to eliminate blistering cause. My question is anybody here having this problem in the past have had re-occurance of blisters after application of barrier paint/other corrective measures? Or the best solution is boat repair and immediate sale? I don't like such development. Please advise any comments, thanking in advance.

THIS IS REALLY DISTURBING ......... if it is an issue that actually happens, the ballast water causing the blistering .....

[Hamin' X]

I could see some migration of water from ballast tank to gelcoat, if the boat were on the trailer with the tank full (really bad idea). However, with the tank full and the boat in the water, the outside pressure will be greater than the inside pressure, so I can't see the ballast water migrating under this circumstance. Not an expert opinion, just a common sense observation.

~Rich

[Catigale]

The pressure of the water on the outside wont act to stop the pressure of water trying to permeate the layup of FG...these are two different animals...that being said, worrying about this is comparable to worrying about an engine falling off a passing A380 ....or maybe I should say of a 747....

[Andrey-314]

We are commencing blistering repair started last year and I would like to share some observations discovered and proved (at least for me) connecting to this discussion.
First of all blistering is an OSMOTIC process, nothing else. Not a "cosmetic issue" as bottom part of blistered gelcoat found wery weak (lost of strength) during cleaning it off.
Process initiated by water penetrating from OUTSIDE, not inside from ballast tanks causing chemical reaction with laminate, you can see microscopic needle holes in laminate in the center of each blister.
I have a layer of epoxy primer (not a barrier paint) applied for next antifouling paint prior first launch but this was useless - I got mass blistering at the end of second sailing season. Barrier paint must be applied prior first time to water to avoid a NIGHTMARE of blistering repair. I mean real repair not just sanding off blisters and covering them by interpaint or other barrier paint which will not stop destructive osmotic process. First of all damaged gelcoat should be completely 100% removed up to clean laminate under the waterline.

This should be arranged very carefully to maintain a lot of things right a way. Next layer should be epoxy resin (if ambient temperature permit) or polyvinyl resin 1-1.5mm thikness (6-7 layers) followed by primer and antifouling in case of epoxy or gelcoat+primer+antifouling in case of polyvinyl resin used as a first layer.

This will guarantee hull from blistering at least 7-10 years. Of course if you will not get hull blisters ABOVE the waterline... Do hope it's a joke. Not sure. For sure I can answer the question causing this post. Yes, it is a lemon.

[DaveB]

Do you mean something like this?

http://s182.photobucket.com/albums/x25/ ... el%20redo/
Dave

We are commencing blistering repair started last year and I would like to share some observations discovered and proved (at least for me) connecting to this discussion.
First of all blistering is an OSMOTIC process, nothing else. Not a "cosmetic issue" as bottom part of blistered gelcoat found wery weak (lost of strength) during cleaning it off.
Process initiated by water penetrating from OUTSIDE, not inside from ballast tanks causing chemical reaction with laminate, you can see microscopic needle holes in laminate in the center of each blister.
I have a layer of epoxy primer (not a barrier paint) applied for next antifouling paint prior first launch but this was useless - I got mass blistering at the end of second sailing season. Barrier paint must be applied prior first time to water to avoid a NIGHTMARE of blistering repair. I mean real repair not just sanding off blisters and covering them by interpaint or other barrier paint which will not stop destructive osmotic process. First of all damaged gelcoat should be completely 100% removed up to clean laminate under the waterline.

This should be arranged very carefully to maintain a lot of things right a way. Next layer should be epoxy resin (if ambient temperature permit) or polyvinyl resin 1-1.5mm thikness (6-7 layers) followed by primer and antifouling in case of epoxy or gelcoat+primer+antifouling in case of polyvinyl resin used as a first layer.

This will guarantee hull from blistering at least 7-10 years. Of course if you will not get hull blisters ABOVE the waterline... Do hope it's a joke. Not sure. For sure I can answer the question causing this post. Yes, it is a lemon.

[Divecoz]

DaveB .. Yes as from your pictures.. when I think of blister issues? THAT is what I envision.. Not the pin pops ( smaller than the head of a straight pin, less than 3/32's of an inch in diameter) I see on mine or other Mac boats .. Yes mine should be repaired.. However IMHO if they are not and the F.G lay up is proper that F.G is not going to degrade as shown.. Our Gel Coat is porous..
Why might we have the pops? Tiny voids ( during fabrication.. so much as a speck of dust ) between the F.G. and the gel coat.. Gel coat is porous and water travels through to the epoxy and is there by trapped between those two layers. One issue or another causes expansion and POP! or pin bump..
With close to, if not more than 10,000 of these boats plying the waters of the world.... I have yet to hear of what I think of as blister issues with any of these boats..

[Catigale]

They definitely can blister, but the only ones bleating about FG failure are the folks getting the bucks for the repairs, imho.

[Andrey-314]

They definitely can blister, but the only ones bleating about FG failure are the folks getting the bucks for the repairs, imho.

Well, if someone have a serious skin rash all over the body the best advice is to visit doctor and eliminate the problem. Another option is to use cosmetics and convince yourself that this is just a cosmetic issue not causing damage to your health. Blistering is an osmotic process, regret it is destructive to gelcoat and laminate by the nature, like it or not.