Hull Repair Needed - Bulging soft spot under bottom paint

[ondarvr]

Re: Hull Repair Needed - Bulging soft spot under bottom paint

Mat comes in 3/4, 1, 1.5, 2 and 3oz weights, no 9oz product is available.

Actual cloth is close to worthless in doing repairs and 4oz is very light, 10oz is much better if you need to use cloth. Any Wal-Mart has fiberglass if you only need small amounts. Any weight mat and any weight roving will work, you can get caught up in the exact style (roving or something like 1708) but either will work.

All of it can be put on at one time, but doing it upside down can be difficult, so you may need to do it in stages.

 

[rfdfirecaptain]

Re: Hull Repair Needed - Bulging soft spot under bottom paint

Mat comes in 3/4, 1, 1.5, 2 and 3oz weights, no 9oz product is available.

If I have to believe you or the manufacturer... well.. I'll take your word for it. I think you can tell by now that I'm detail oriented, so I didn't just make that information up. I called the manufacturer, Bondo at 1-800-421-2663 while I was standing in the store. I punched the technical support button. I gave them the product # for the mat, which is "No. 488". The package says 8 square feet, but there is no weight given.

I questioned the technical support guy becasue I didn't think his numbers were accurate, but he said "No this is some of the heaviest matting you can buy". With that I left without purchasing anything. I went to 2 other stores... guess what... they sell ONLY the exact same product! And with THAT, I made my purchase at the third store and came home.

 

[ondarvr]

Re: Hull Repair Needed - Bulging soft spot under bottom paint

Bondo isn't the manufacturer, they just buy it and put it small packages. It may be they use the same measurement that is used for roving and other woven and stitched products, which is by the yard, meaning its 1oz mat. Mat is measured by the square foot.

 

[Lone Duck]

Re: Hull Repair Needed - Bulging soft spot under bottom paint

A good reference is the West System "Fiberglass Boat Repair and Maintenance",

http://westsystem.com/ss/assets/HowTo-Publications/Fiberglass-Boat-Repair-and-Maintenance.pdf

and a companion booklet "Gelcoat Blisters Diagnosis Repair and Prevention" articles on the West System website:

http://209.20.76.247/ss/assets/howto-pub2/Gelcoat%20Blisters%20Diagnosis%20Repair%20and%20Prevention.pdf

They go into a lot of detail on fixing these kind of problems. You don't have to use epoxy, you can use polyester resin and the appropriate glass products with the same techniques taught in these booklets. I prefer epoxy because it's stronger, but in a good repair polyester is plenty adequate.

Be careful ! If your hull is made of epoxy and cloth , the poly will not stick to it well. If you don't know what the hull is made from, use epoxy, it will stick to poly. poly will not stick well to epoxy.

 

[ondarvr]

Re: Hull Repair Needed - Bulging soft spot under bottom paint

The chances of having a boat built from epoxy are about a million to one and on an older boat even less than that. Its not even a concern on this hull.

 

[rfdfirecaptain]

Re: Hull Repair Needed - Bulging soft spot under bottom paint

GREAT NEWS... the crack does not extend deep into the laminate very deep. See the photos below. The crack was all the way through the gel coat and at it's worst 1/8" into the laminate, but not quite that deep the entire way. I see no evidence of "white glass" based my knowledge of that type of problem. The laminate is very solid.

This poses more questions for me. I was prepared to grind deeper into the laminate to get to "solid" glass. Now that I have proof that this crack wasn't as bad as suspected I'm wondering if I need to keep going with the same plan.

The plan was to use polyester resin and several "layers" of choped mat with a final layer of cloth.

Should I still do that?
Should I only put on 1 layer of glass?
Or, should I just recoat this whole area with gel coat and repaint with bottom paint?

I don't want spend a week over doing it. What's the logical repair now that we can see the extent of this crack?

 

[Yacht Dr.]

Re: Hull Repair Needed - Bulging soft spot under bottom paint

Hello Cap..

Using just mat should be fine ( 2 layers unless its deeper in areas ) . I would nix the cloth alltogether.

Better grind job this time .. though on the trans you might consider evening up your grind parameter. No jig jags thing .. flow your grindouts like on the bottom . Its a whole lot easier to lam.

Looking good

YD.

 

[rfdfirecaptain]

Re: Hull Repair Needed - Bulging soft spot under bottom paint

YD... great to hear from you.

I went ahead with the mat layers. There are a total 5 layers on the corner of the stern/hull. That area (Laminate) got knocked down just a little more than I wanted with the aggressive ginding wheel (50 grit). In other areas there are just 2 layers of mat. All 5 layers are feathered out nicely and I'll let them cure overnight.

Tomorrow I plan to grind and smooth out my work with a less aggressive pad and then start applying the ONLY gel coat I could find within 50 miles.... it's West Marine's "Laminating Gel Coat". It's not as thick as I had hoped since I am working upsidedown. It's not as thin as paint, but it's not like syrup either. So, I plan to just keep putting on plenty of coats all day until I get a nice build up.

Any suggestions?

 

[Yacht Dr.]

Re: Hull Repair Needed - Bulging soft spot under bottom paint

Its bottom paint right ? ... so why why gel ?

Return the gel and put 2 coats of epoxy over it scuff..then bottom paint it.

Or you could Just paint like some do.. ( if its a good lay up ).

BTW.. for your prefairing.. you might want to sand the parimeter flush first..then work inward. Sand the outside of the repair smooth then get a flat stick and lay it across to see where the Highs are..

Fiberglass laminating and grinding is EZ... Putting it back in shape Is a Whole different experience .. dont go fast and keep whatever you sand with flat heheh..

Cheers

YD.

 

[rfdfirecaptain]

Re: Hull Repair Needed - Bulging soft spot under bottom paint

YD...

Can you give me some options on the epoxy? Name some epoxy brands and locations where I might be able to purchase it. Is there a substitute that works just fine, but doesn?t have the ?marine grade? title, thus making it an unsuspecting substitute?

FYI.. I searched for epoxy at boating supply stores when I broke down and bought this gel. I can't find "marine" epoxy anywhere. West Marine, the only place that even sells it, said it was on back order. The worst part is they have several different kinds and they didn't have any of them in stock or their warehouse. That's why I went with the gel.

 

[rfdfirecaptain]

Re: Hull Repair Needed - Bulging soft spot under bottom paint

Well, with no marine epoxy anywhere to be found I went ahead with the gel coat. This was my last day off until Friday. Here?s what I accomplished today:

1. Sanded smooth the polyester resin layers I put on yesterday.

2. Prepared area for epoxy putty: brushed, air pressure then wiped several times with acetone

3. Used Loc-tite epoxy putty on the gouge and other 3 low spots on the left side of the first photo

4. Ground the epoxy putty down smooth with the existing gel.

5. Prepared entire area for gel coat: brushed, air pressure then wiped several times with acetone

6. Mixed 2 oz. of gel and applied with a 1.5 in wide foam disposable brush

7. Repeated step #6 three more times with about 20 minutes between coats.

8. The last and 4th gel coat? I put it on heavy, then immediately covered all of the gel with wax paper and rolled smooth

Friday I will remove the wax paper and tape, then sand and feather out the cured gel coat. I will also try to get the bottom paint on and post photos. So far this has been a pain, but truthfully, the first time is the worst. I wouldn?t hesitate to do this again, now that I?ve done it once.

So, if I did it wrong this would be the time to tell me that I should have been more patient and waited for your response. If so, I guess I?ll just have to suffer the consequences?. The fish are biting!

 

[Yacht Dr.]

Re: Hull Repair Needed - Bulging soft spot under bottom paint

YD...

Can you give me some options on the epoxy? Name some epoxy brands and locations where I might be able to purchase it. Is there a substitute that works just fine, but doesn?t have the ?marine grade? title, thus making it an unsuspecting substitute?

Hi cap..

One thing here.. I did say in some other post that Iboats isnt one person.. and certainly NOT me lol. There ARE MANY here among us that can help you. Sometimes even better then me ( Im no epoxy expert ).

Now then.. Your fine with your repair with the gel..fair it out and Bottom paint that thing and go catch some jumpin fish

You cant be wrong on the finish coats that cant be easily fixed. In fact the gel could end up being a Primer coat for more fairing which I personally do from time to time.

Na your good as long as the glasswork was done right

YD.

 

[rfdfirecaptain]

Re: Hull Repair Needed - Bulging soft spot under bottom paint

YD...

You're right. There's a plethora of information available from lots of folks. But, in my case only you and ondarvr have stuck with me the whole way through this and the previous project.

Of course I owe a great big thanks to everyone, but I don?t think I could have made it without you two guys.

 

[Yacht Dr.]

Re: Hull Repair Needed - Bulging soft spot under bottom paint

Sweet ... you hear that onda... I think we should get some royalties on this thing ( I like labatts blue ) .

Seriously.. we jumped in..and that was that. Im sure alot of members didnt chime in because the thing was handled ( I do that myself..seeing that someone allready has a direction thats in the best interest of the poster ).

Na.. you could have done it with other members here m8.. we just happend on ya .

Again..there are Good experienced members here. Not just Ondarvr and myself and I respect them ( at least they had the right mind to stay out of such volitile threads as " cough thanks guy for fixing that last debockle thread " thing ).



Peace ..

YD.

 

[rfdfirecaptain]

Re: Hull Repair Needed - Bulging soft spot under bottom paint

FINAL UPDATE:

Well, it's done! At least almost done.... going to add 1 more coat of bottom paint Sunday afternoon. The pics below show the sanded gel that has now been painted back with fresh bottom paint. The paint is still a little wet in spots, but soon the bottom with be wet with salt water! Horrray!!!!

Thanks for all your help gang! With your advice and this tiny bit of experience, I wouldn't hesitate to tackle something like this again.