Bulkheads and such . .

So, I recently purchased an un-used, used Old Town Egret kayak. Although it was a steal, it didn’t come with a forward bulkhead / hatch. (looking for a quick way to sink a boat, fill the front 2/3 of a 14’6"er with water!!)

Anyway, I Ebayed some cheap minicell, made up a bulkhead and pressed it into place. I also installed a 6" screw in deck hatch up front to get to my newly acquired ‘dry space’

Ive read a bit on this, and might already have the answer, but info is free, and opinions are aplenty . . .

I silly-coned the cockpit side of the bulkhead upon installing it - I didn’t know better - and alas it doesn’t stick to the polylink-3 hull (linear poly)

So what I need now is something that will . . . a good sealant for the bow side of the bulkhead that I haven’t contaminated with the silicone.

Can anyone tell me what the manufacturers use on poly hulls? I’ve read that Lexel will work, but whatever the factory used on the rear bulkhead seems to be the stuff, and I’d like to replicate it. Also, does the factory sand/flame the poly prior to sealant application??

Any help from someone in the know would be great. It’s too cold here to apply sealant for now, so I have a bit of time . . thanks

Tube Of Lexel Sealing Adhesive

The most important step when using adhesive in poly boats is to use a flame of some kind. Maunfactures use a propane torch. By grazing the plastic with a flame you are causing the pours to open up and accept the adhesive into the plastic rather than sitting on a smooth surface. The flame should be moved quickly across the surface, you are not trying to melt anything, just heat up and modify the structure of the plastic.

Oh yeah, lexel is definitely what I recommend too.

I Would Avoid Flame
and not risk a costly mistake. Use rough grit sandpaper and clean off the area with alcohol.


Yeah,… no flame on polylink-3 (nm)

bulkhead and such
try useing sikaflex it will stick to anything its what we use to fit our bulkheads in boats it will work.

A flame treatment of the surface can improve the bond strength on polyethylene, but it has nothing to do with “opening up the pores.”

It increases the surface energy of the plastic, which gets into molecular physics that I don’t understand.

Anyway, Lexel is known to work well.

over simplified
yes, you are polarizing the poly, but I though opening up the pores was an easy way to explain it. The plastic changed molecularly and if you want the bulkhead to have a chance, whether you are comfortable or not, using a flame is the way to go. Check out the video of Venture Kayaks building an Easky on their website. You will see just before the bulkhead is place, a kid using a propane torch flaming the inside of the boat. It’s at the 4 minute mark in Part 1.

Thanks all . . .
The information was very helpful!!

I pulled the silly-coned bulkhead out and made a up new one (the first was horribly contaminated with silicone) using 2 sheets of 1" minicell, reinforced with a 1/4 thick piece of PVC sheet sandwiched between them, all contact cemented then clamped together between two plywood sheets for an hour …

Headed out to the local Ace hardware and picked up two tubes of Lexel. When I got back I thoroughly cleaned the silicone out of the hull, scrubbed it multiple times with 99% isopropyl alcohol, then scuffed with 120 grit dragon skin. Flamed it all the way around, then stuck the new bulkhead in.

I applied the Lexel to both sides of the new bulkhead (wow, it sticks to everything!!!) and tooled smooth.

We’ll see in a day or two how it turned out (takes two days to firm up, 2 weeks to cure) I’ll post an update in a few . .