How should I support this?

Basketcase · #1 08-20-2012, 05:10 PM

Hey guys. First thing on the list for the project 20cc is to repair the repair that was done on the center of the bottom of the hull. Not sure what happened here but I need to bring the repair up to my standards. What I plan to do is to cut the center stringer as level with the hull as possible, grind/sand the repair area and lay a layer of 1708 and a layer of woven roving down the entire lenght of the hull. Then I'll place the center stringer back in and use some 1708 tape to reattach it.

My question is, given the current state of dissasembly, do I have to worry about any distortion when I remove/reattach the center stringer? It's sorta sitting on a trailer right now but I plan to pull it off the trailer and set it on blocks before I do this. Just wondering about placement of blocks etc. I had some distortion on the last boat I did and I've seen that some folks on here have had this problem as well. Will I run into it here? Thanks! Heres a picture of what I'm working with.

strick · #2 08-21-2012, 12:53 AM

I dont think you will have any distortion. That has been done before here on this site. What is wrong with it? hard to tell in the photo. It would be better to glass the entire center keel stringer in place then just tab it in place with 1708.

strick

Basketcase · #3 08-21-2012, 07:55 AM

Thanks strick. I'll go ahead and add more glass to my plan.

There is an old repair that was done that is visible from the outside. Looks like someone took some light cloth and ran about a 3" strip for about an 8' length right down the center. Maybe the boat went on some rocks or something. There is a spot on this repair where it has cracked or delaminated. I know this because after a heavy rain we had (I dont have this covered yet) even though its heavily tilted and the plug is out there was some water seepage coming out of this crack. If water can get out of the boat, water can get in. I also plan to throw a couple layers of glass on the outside after I get the inside all set. Also thinking I may wait until the transom is in so I can tie the center stringer into it in one step.

Also, Strick, on your 20 your stringers were hollow and you filled them with foam. Mine are already filled with foam. Is it just something they did differently from year to year? Thats another reason I want to crack that center stringer is because Im betting the foam is wet.

strick · #4 08-21-2012, 08:48 AM

Quote:

Originally Posted by Basketcase

Also, on your 20 your stringers were hollow and you filled them with foam. Mine are already filled with foam. Is it just something they did differently from year to year? Thats another reason I want to crack that center stringer is because Im betting the foam is wet.

I think your boat is a 1970? Mine is a 1969 Yes mine were hollow but there was foam in the spaces between the stringers . I guess in 1970 they decided to fill them with foam. The center keel stringer is all wood.

strick

Wildman · #5 08-21-2012, 10:31 AM

You will want to take it off the trailer and get it as low to the ground as possible. Make sure you can leave it in this position for the amount of time it will take you to get the structure back into the boat. You will notice once you get it blocked up, and take the stringers out the boat will flex underfoot.

I used a 6x6 landscape tie under the stern area where the transom meets the keel on my boat. The lower you can get it, the easier it will be to get materials/people in and out of the boat. I used short screw jacks and blocks to adjust the boat side to side /corner to corner making constant measurements in an X pattern so the boat didnt turn into a potato chip shape. Without a transom core and a deck fiberglass boats turn into a Jello mold.

Here is what it looked like after I poped the center stringer out, I had plenty of poor repairs and installs in the hull to fix.

I ground it down smooth, dried it out and then stuck my center stringer down with putty, and made nice smooth fillets along the sides. This is actually the raised portion for the tank support, but I used the same paint sticks to support the stringer while the putty setup. You get the idea.

Basketcase · #6 08-21-2012, 07:19 PM

Nice. Thanks for the pics, Wildman.

So do we think the wood is significant? I was thinking that if I am able to salvage the fiberglass of the center stringer, that I'll just reattach it, glass the heck out of it and fill it with foam. Oooooor, I have 4 sheets of "surfboard foam" that I think are about 5' long, 2" thick and 2' wide. Seems like this would make a decent stringer if I needed to shape and cut one out to be wrapped in glass. I was also hoping to use the foam for some lateral stringers in front and behind the fuel tank just for kicks. This foam I have is quite dense and hard but easily shaped and formed. Not sure what it would compare to, but it seems like itd be a great core material for some parts. Probably not strong enough for a transom though??