Hull repair

bostonjake01 · Post by **bostonjake01** » Fri Aug 29, 2008 7:54 am

I am getting ready to start on repairing what looks like a bad attempt at a hull repair and I figured i would get a liitle advice on this before I tackle it
I figured I would get the old glass repair off and then start out fresh any advice
http://s432.photobucket.com/albums/qq47/bostonjake01/
there should be a close up of the hull damage area in the pictures
thanks Rich

jav · Post by **jav** » Fri Aug 29, 2008 8:19 am

Rich,

why do you thing it was a bad repair? Is it delaminating? or does it just look bad?

bostonjake01 · Post by **bostonjake01** » Fri Aug 29, 2008 11:01 am

a little of both, I just posted more pictures what do you think

jav · Post by **jav** » Fri Aug 29, 2008 11:17 am

Still tough to see but it looks like the repairs were done with chopped strand mat. If so, yes, I'd grind them off and start fresh.

Chopped strand Mat (CSM) is usually NOT compatible with epoxy resins which would mean these repairs were likely done with polyester resin. Polyester resin is great in a chemical bond lay-up (when all layers are done in a mold at approximatly the same time) but, in a secondary bond application like this, epoxy would be a much better choice.

Also, I'd use cloth, (not CSM) as the strength to weight ratio is much better. Keep in mind that once you use epoxy, you need to overcoat with other epoxy products since polyester fairing compounds and gelcoat do not work well over epoxy.

wowzer52 · Post by **wowzer52** » Fri Aug 29, 2008 12:51 pm

As I look at the pictures I do not understand how a boat gets that way.

bostonjake01 · Post by **bostonjake01** » Fri Aug 29, 2008 5:25 pm

thanks Jav, I was about to ask which cloth would be better so thanks for answering that ahead. since all of the damage is in the water line I should be able to repair the hull and then just bottom paint right over the fiberglass, right?
wowzer to answer your post I was told by the previous owner that she broke off her mooring which scares me because I intend on mooring her once she is done.

chucka · Post by **chucka** » Fri Aug 29, 2008 8:38 pm

From the photos, it looks to me like there are some places where the patch was applied over old bottom paint, which is very bad for adhesion. I would grind it down to expose original glass. All paint should be stripped off beyond the outer perimeter of the patch to assure solid adhesion. I've had great luck with West systems epoxy for hull repairs on my F-26. Grinding it down to clean, fresh, solid material before applying the patch is key.

I've kept boats on moorings for years without issues. A mooring, if maintained properly, is as reliable if not more reliable than being tied to a dock in bad weather. The boat is free to move in response to wind and seas, but you need to inspect and maintain the tackle from the mooring to the deck hardware, and replace stuff that wears out. Shackles and chain corrode, line abrades, deck hardware can come loose. usually none of these things happen overnight.

jav · Post by **jav** » Sat Aug 30, 2008 9:05 am

bostonjake01 wrote:thanks Jav, I was about to ask which cloth would be better so thanks for answering that ahead. since all of the damage is in the water line I should be able to repair the hull and then just bottom paint right over the fiberglass, right?
wowzer to answer your post I was told by the previous owner that she broke off her mooring which scares me because I intend on mooring her once she is done.

I would use something on the order of 8-10 oz. cloth. Good advice about surface prep above... you need to bring the surface to be repaired all the way back to good, sound, clean fiberglass before starting to build it back up.

As far as bottom painting right over the epoxy repair, you can do that but getting the surface fair (perfectly countoured to match the adjacent hull form) is going to be tough. The normal method is you do the structural repair with resin/cloth and get the shape close. Then you apply a fairing compund over the whole repair and longboard/block sand the final shape. A barrier coat is a good idea over that. Then you bottom paint.

All the while, you need to make sure every product you use is approved for use below the water line. Thats very important because many products are not.

wowzer52 · Post by **wowzer52** » Sat Aug 30, 2008 9:39 am

I love to see old boats come back to life, what a gorgeous boat. kudo's

bostonjake01 · Post by **bostonjake01** » Sat Aug 30, 2008 1:05 pm

thanks for the info I went ahead and repair a small area in the bow area.
I would like to post pictures directly on the forum. I updated the pictures here with the glass work please give me feed back and advice dont worry about hurting my feelings I just want to do a great job.

http://s432.photobucket.com/albums/qq47/bostonjake01/

bostonjake01 · Post by **bostonjake01** » Tue Sep 02, 2008 2:14 pm

come on guys i'm looking for help here I am not sure if this is the way to repair the hull I could really use some advice.

jav · Post by **jav** » Tue Sep 02, 2008 3:42 pm

jake,

you should post the appropriate pictures here so we can tell what you've done. I went to your photo site and had to scan all of them and can't tell whats been updated.

Beyond pictures, you should describe what and how you did the repair.

bostonjake01 · Post by **bostonjake01** » Tue Sep 02, 2008 5:20 pm

this is a small hole that I grinded down

this is it after I used fiberglass cloth with polyester resin both are bondo name brand, I layered about 8 sheets one ontop of the next while still wet and I did it from the out side.

now this is a large hole that was repaired before I got it and it doesn't look right I see some fiberglass peeling, it also look like it mat fiberglass not sure if this is ok or not and want to make sure it's done right, does this work have to be done from the insde or can i do from the outside
any and all advice would be great.

here are more pictures I just took

jav · Post by **jav** » Tue Sep 02, 2008 8:31 pm

OK - Nice job on the pics but we need to work on the repair. Looking at the 1st pic... you didn't grind enough. You have to remove all the gel coat (all the white) and get back to clean, structurally sound fiberglass (the pink color). Any repair done over gelcoat could fail at the gelcoat.

The grinding should taper back from the center of the repair, meaning deepest grinding at the center and gradually less as you work away from the damage. The longer the ground taper, the better the repair. Some guys recommend a minimum of 8 to 1 and I like at least 12:1. This means if your repairing a 1/4" depth, it needs to be tapered at least 2-3" on all sides beyond the repair. If the damage is through, you can put a temporary backing plate behind it (just cover it with plastic so the epoxy doesn't stick.

The prep is the most important part! It needs to be ground correctly, then cleaned correctly (with acetone or other non residue cleaner), then re-layed correctly. There are some reasonable repair books that have good illustrations of this. I highly recommend getting one before you get too deep into the project.

bostonjake01 · Post by **bostonjake01** » Tue Sep 02, 2008 8:55 pm

thanks alot jav, could the repairs be done from outside or inside?
do you know were i can get any books to help me?