Replacing rotted core with Klegecell?

[renbluefish]

hello everyone,

I am replacing the balsa core on my Kalik 44. I will begin removing the teak deck this month. I found an article in Cruising World where some one had replaced their core with Klegecell.
Has any one used this product or have seen it used? I have emailed a possible distributor in the North East and waiting for the pricing of the product.

[Gary M]

That is a common material to replace balsa coring with . Several spots on my boat have had that treatment. It has the advantage of being a closed cell foam so it will not absorb water or rot. It is slightly less dense than balsa so you my notice some give in the larger flat areas.

If you can totally seal off balsa, it is still my first choice but in Klege cell works well.

[mitiempo]

I agree with Gary. End grain balsa is the best core. Any core can delaminate if not done properly and if hardware isn't properly epoxy potted water intrusion will be an issue. End grain balsa has the best compressive strength of any affordable core I know of.

[renbluefish]

thanks for your opinions, still waiting on pricing. I think balsa will be the choice, will post later with my results.

[paulk]

Using a different material can affect the properties of the deck: note Gary reporting "some give" in areas he put in the foam core. If the deck is "giving" it is going to end up cracking there eventually, and water is going to get in again- leading to a repeat of the problem. Using the same material throughout will help avoid this problem.

[docket]

I redid the deck on my Kalik 44 and I used balsa. It has held up for 10 years just fine and I liked the fact that the balsa absorbed the west system epoxy.

[renbluefish]

thanks docket, after more research i will be using balsa core.

[SoulVoyage]

In stages during a period of about 5 years, I replaced nearly ALL of the end-grain balsa on my 1963 Allied Seawind with a closed-cell foam that I originally thought was a derivative of Klegecell, but it turns out it wasn't....it is FAR superior to klegecell. If I remember correctly, isn't klegecell bluish in color...sort of aqua-marine?? This new stuff is light-grey.

The stuff I ended up using is light-grey in color and re-inforced with glass-fibers on top and bottom layers. It seems to have absolutely MASSIVE compressive strength, and yet is extremely light. I was getting it at a substantial discount as "drop-off" pieces from a yard that was re-decking a "money is no object" power-yacht.

The stuff looks like it would work on the space-shuttle....it looks and feels high-tech! I have no idea what it's called (maybe one of the boat-builders amonst us can help, here), and I'm sure its "retail" price is HYPER-expensive.

I used klegecell in other areas of the boat, and this new stuff DOES seem work better!!

Heretofore, end-grain balsa was the core of choice, amongst high-quality builders of note. I think that pendulum is starting to swing, or maybe has already swung towards producs like this grey stuff.

The problem with end-grain balsa, is that it WILL soak up water through capillary-action. If you use balsa, you have to re-bed ABSOLUTELY RELIGIOUSLY (not a bad idea, anyway).

If balsa is kept dry religiously, it is GREAT stuff...to be sure, there were sections of it on my cabin-top that were still PERFECT after 40 plus years (she's a 47 year-old boat, now).

However, the decking fiberglass top & bottom layers on the old Seawinds are so THICK that you really don't even realize you have a problem until someone comes along with a moisture-meter!! During that re-coring project, I probably took away maybe 500 pounds of soaked, mushy balsa. (maybe not 500#, but it was A LOT!).

I have no idea what boat you have, so you may not have the luxury of having such thick top & bottom fiberglass deck layers, so if it were me, I would be fairly wary of putting it right back in. You're taking it out for a reason...it's wet.

Maybe someone here can come up with the name for that light grey fiber-glass reinforced closed-cell foam.

One additional note: I stopped using plywood for between fiberglass layer reinforcements where needed in high-stress areas(like under lifeline stanchion-bases, etc) and began using cheap whitish plastic cutting-boards, instead. Its strong, fairly light, comes in an assortment of thickness, is very cheap, and will never rot!!

Good luck.

[mitiempo]

I think balsa has higher compressive strength than the foams. And water ingress in ANY core is a problem. Proper potting of all fastener holes is important in any cored deck or cabin. And the problem with the plastic in way of the hardware is that some plastics don't bond well with epoxy. A solid glass/epoxy layup is best under stressed hardware. Balsa is less expensive than other core materials as well.