Outside flange joint repair.

Good day to all.

In my attempt to separate the deck from the hull on an old bertram caribbean I cut a few spots higher and lower than the seam. Can this be fixed by re-glassing these spots without compromising the strength or is it advisable to cut the whole flange of and glass a box joint from the deck over the hull.

I have not worked with fibre glass before and am not sure of the capabilities.

I was given this boat by a friend who had it in the yard for at least a couple of years. Transom needs replacing as well as the floor and the ceiling. This forum is a great source for a rookie and I'm sure I can get some good tips here.

Many thanks and I hope I can get some pics up soon.

Re: Outside flange joint repair.

No more cutting for you. I would repair the bad spots rather than cut more.

Re: Outside flange joint repair.

Pictures would sure help, but if its fiberglass, it can be fixed. Post up some pics. I love old berts.

You can get rid of the seam where it laps over but it is a lot of work and a lot of material. This thread has a boat that was done that way and it looks awesome. I think its around page 10, but I don't think they cut the flange completely away. http://www.bdoutdoors.com/forums/check-out-my-boat/

Re: Outside flange joint repair.

tpenfield said:

No more cutting for you. I would repair the bad spots rather than cut more.

Click to expand...

I only just started. Still have to cut out the whole interior and floor. Oh yeah and the transom that looks like the hardest part.

Re: Outside flange joint repair.

@chriscraft254

Would love to put some pics up but the message on top here says that that they can't be viewed at this moment. See if I can put in a flickr link of some sort. Need to set it up first.

Re: Outside flange joint repair.

Here's some pics for now via flickr.

http://www.flickr.com/photos/robvanbeek/

Re: Outside flange joint repair.

I just did a small section on mine that i damaged taking it off. I just clamped a mold to the undamaged section of the flange, then I built up the new section until flush with the top of the hull using 2 layers of 1808 the first butted against the outside of the hull and fitting inside the missing section but not going over to the inside of the hull, and just stretching over the old section a tiny bit. The second layer is basically the same but a little longer so it over laps the old flange a little more and with the fibers just stretching onto the top of the hull. To finish it off I used 2 layers of 1 oz csm, each with a little more overlap than the last and this time wrapped aroung to the inside of the hull. This is where I went wrong, I didn't round off the inside top of the hull so I had a square corner and ended up with air bubbles that I have to fix tomorrow but it's really strong and looks good. Make it over sized and then sand it back flush, and don't forget to feather the edges of the flange.

Take a look at the pics in the last post in my rebuild thread, it's the before and after shots.

http://forums.iboats.com/showthread.php?t=507121&p=3633187&viewfull=1#post3633187

Now don't anyone go deleting this thread, I gotta copy all that over to my thread soon

PS
Thank god for the restore auto saved content on this forum, my computer crashed just after i added the smiley, while my mouse was hovering over the post reply button.

Re: Outside flange joint repair.

That's a formica type board, it's like thin wood with a shinny white coating on one side. On the edge that's against the hull it's glued to the skinny end of a 1x2 but you may need to find something a bit more flexible I think. It's also waxed and coated with pvc so I can get it off when it's set. I coated the the 1x2 as well just to be sure that any exess resin wouldn't glue it to the hull

Re: Outside flange joint repair.

Thank you all for the great tips.

@three08

Great pictures on your thread. Your damage is minimal compared to mine. I'm not sure if just layering will supply sufficient bonding strength for my mishap. I have a couple of sections of at least a foot long. The flange on the deck however is still ok all-round. However, as I mentioned before, I am not familiar with the capabilities of glass fiber. I have read one of the west system publications on boat repair and in order to get a good bond preparation is crucial.

Perhaps in order to achieve a strong bond with the hull I'd use your tip of the formica on a piece of 1x2 with the pvc somehow attach it to the hull and work from the prepared inside of the hull folding it over the formica. I might use a bit more material this way but it should stand the test of time in my opinion.

I would love to see more opinions on this though. I'm learning everyday.

I see a belt sander in your pic. Does this work well on your deck and hull or do you use an orbital sander as well. Just asking since I haven't started the sanding process yet.

Re: Outside flange joint repair.

Rob van Beek said:

Thank you all for the great tips.

@three08

Great pictures on your thread. Your damage is minimal compared to mine. I'm not sure if just layering will supply sufficient bonding strength for my mishap. I have a couple of sections of at least a foot long. The flange on the deck however is still ok all-round. However, as I mentioned before, I am not familiar with the capabilities of glass fiber. I have read one of the west system publications on boat repair and in order to get a good bond preparation is crucial.

Perhaps in order to achieve a strong bond with the hull I'd use your tip of the formica on a piece of 1x2 with the pvc somehow attach it to the hull and work from the prepared inside of the hull folding it over the formica. I might use a bit more material this way but it should stand the test of time in my opinion.

I would love to see more opinions on this though. I'm learning everyday.

I see a belt sander in your pic. Does this work well on your deck and hull or do you use an orbital sander as well. Just asking since I haven't started the sanding process yet.

Click to expand...

I'm no expert but judging by the strength of mine you wont have a problem, the only way I can see that would make it any stronger is to sand the top edge of the hull down a little so it's flush with the bottom of the flange, doing it this way each layer will wrap over the side instead of just the last 2 making it a little stronger. Also sand down the inside of the hull by about the thickness of the flange so you can sand it flush when your finished without losing strength. As you said preparation is crucial, the other thing that helps is to do all the layers at once for the best possible bond, but there is a limit to how much you can lay up at once, the most I've done is 2 layers 1808 and 2 of 1 oz csm without any problems but I think if I needed much more I would of waited for it to get tacky before continuing. btw are you using polyester or epoxy resin?

The belt sander is great but you have to be really careful not to take to much off,. I used it mainly for getting the glue off the transom and sanding repairs down flush. Never use it on gellcoat unless you want ALL the gellcoat gone. I use an orbital sander on anything with gellcoat and anywhere I'm worried about taking off too much glass.

Re: Outside flange joint repair.

@three08

Not sure what I will use. Polyester or epoxy. I haven't stocked up on it yet. I have to find out what was used on the boat when they build it. I guess it's polyester judging by the smell when cutting it. I have read that epoxy resin is superior to polyester and from memory it had something to do with shrinkage. The supply store probably can help me out a lot with this. The west system guide for boat repair I bought is a great help for me in determining what to use. The woven mats are expensive here though. $8,60 a metre. Haven't priced the csm yet.

For now I'm still in the process of demolishing the interior, floor and transom. I have only very limited time at the moment so I guess that will be finished in the next week or 4. Then I start rebuilding a little at the time. I have really underestimated the amount of work on this boat and to top it all of I noticed some hull damage. The sun was shining on the inside and I noticed light coming thru the hull on one side in two spots. A very cheap paint job seemed apparently sufficient for the previous owner to fix this.

Re: Outside flange joint repair.