Inner hull layup

[timelyne]

I posted earlier about my 22' Bayliner hull. I took a good look at it and decided to take the entire inner layup out. I have pulled the power plant and have finished stripping all of the old Balsa out. It wasn't as bad to do as I had thought it may be as it was pretty much rotten. My questions are what is the best materials to replace it with? Both in resin and wood or ? Plywood might work as the hull slopes towards the V of the boat but is quite flat as it slopes down. Also should I treat the wood, if that is what I should use, with a preservative before I coat it with resin?<br />Any help is appreciated.<br /><br /> Tim

 

[Bondo]

Re: Inner hull layup

Core-mat is what you need.... Plywood will be to stiff.. This Isn't a common rebuild... Most boats with this kind of damage are Junked... You're dealing with the Actual Hull, Not some sort of stringers or whatever...<br />Whatever you use, you Must build it to the same Specs as the rest of the hull in that area... You Don't want a Stiff, or Soft spot...Flex between your repair,+ the original sections could be Catastrophic....

 

[Kenbo]

Re: Inner hull layup

You really have got yourself a project. If you want to keep the structure as designed, why not replace the balsa and redo the lay-up. "Baltek ContourKore" is probably very similar to what you removed. Check out www.defender.com , they carry it. When doing this, you will want to plan everything carefully before you start and make sure you are all set up before mixing resin. Make sure the inside hull surface is thoroughly sanded, clean and dry. You will want to put down a layer of chopped strand mat(well saturated with resin), liberally coat the down side of the balsa core with resin, and press firmly in place. Stop and let everything cure. I would recommend that you work in manageable sections and don't get ahead of yourself, Catalized resin waits for no man! After the core layer cures, you will want to go and fair in the edges of the balsa and fill in any voids so that you have a smooth fair surface to do your inner layup on. Fiberglass hates corners! I would liberally apply a coat of resin (use a little extra catalyst) to the surface of the balsa and let it cure to seal the pores in the balsa before beginning the inner layup. That end grain balsa is like a sponge. Sand the surface and begin your inner layup. Start with a layer of chopped strand mat for adhesion and alternate with woven roving. I always finish with mat because I like the surface texture better and the roving fibers aren't exposed and subject to wear. You will want, at a minimum, the following items: Air bubble rollers (curved and flat), respirator with good filters (the fumes really get to you, especially inside the hull), and rubber latex gloves (dishwashing gloves from the supermarket work well). Sorry to be so long winded, just trying to help. Good Luck!!

 

[jomac]

Re: Inner hull layup

TR Kenbo is right if your bay was built in south GA Baltek was the brand of material they used core mat was used only on the sides of the hull to prevent the woven from printing though the gel coat

 

[BillP]

Re: Inner hull layup

Always hot coat end grain balsa with laminating resin before glassing...otherwise it will suck the resin out of the cloth and leave a dry (weak)layup. With close examination you will see millions of pinhead size air bubbles when this happens. I've seen this many times with open cell foam too (such as used in Bruce Roberts sailboat plans).