Glue minicell to fiberglass/kevlar?

I am making some major changes to my QCC-700.

I took out the Smart Track rudder controls and installed an “Onno Gas Pedal”, WOW, is it cool! Very easy to do with Patrick’s directions over the phone.

I also tore out the seat pan, and was carving and shaping a new seat out of minicell all afternoon.

Here’s my question to everybody:

What can I use,from the local hardware store, to glue minicell to fiberglass/kevlar hull?

I’m thinking contact cement?

Or a two part epoxy?

Or…What about spray foam insulation, the kind that expands and gets hard? I know this stuff expands like crazy, and if used improperly could possibly break or crack my boat.

But I think if I use it sparingly, almost like a glue, running a bead of the stuff around the perimeter of the seat, and then squish the seat into the foam before it sets up, I think it might work? That darn stuff sticks to everything I’ve ever used it on. I’d probably have to trim excess foam later, but no big deal.

I’d like to cover the minicell seat with neoprene. Any suggestions as far as that goes?


Paul Lueders (Agongos)

I like DAP …
weld wood green label been using it about 5 yrs in salt water on plastic and glass it dosen’t have to kill you to be stong and when its time to change it you wont have to chisel it

Plenty of options
Weldwood or other contact cement will work - if you have a nice tight fit between the bottom of the seat and the boat. Contact cement has zero ability to fill gaps.

Lexel would be fine. Probably any latex caulk/sealant would work fine.

3M 5200, PL Ultimate or similar one-part moisture activated urethane adhesive will work.

Epoxy will work, but also has poor gap filling properties unless you thicken it with micro-balloons or cabosil.

If done properly, all of the above will be really difficult to undo. Make sure that you are really and truly happy with the location before you commit to an essentially permanent installation.

In reality, with a good tight fit, you probably don’t need to glue a foam seat in place. A few permanent marker lines to indicate the right spot and a tether to prevent loss will do the trick, allow adjustment for trim and make cleaning easier.

More info…
3M Super 77 is good stuff. The spray can makes it very easy to apply. Works great foam to foam. I would resist gluing your seat to the boat. If you assemble the mini-cell components cleverly, you can wedge your seat in place with your thigh-blocks and seat back. This makes it easy to pull apart and tweak whenever you want. I’ve also seen people use velcro on the kayak floor and the bottom of the seat pad to allow re-positioning. I tried it once, worked great and was pretty solid… but eventually the velcro adhesive let-go in the wet environment (even using industrial strength velcro).

Here’s a picture of my surf boat with full minicell outfitting… very few components are glued together, mostly they are wedged in place.

A good resource for materials and ideas is:

Even if you choose to permanently attach your seat to the boat with some gnarly stuff… I would use velcro for a few test drives so that you can experiment and get the seat position just-right.

Marine Goop. takes awhile to cure
but you better be sure everything is the way you want it once it does.

Barge is said to work well
I forget what I glued my minicell pads in with…

They are getting kind of ragged and getting them out to be replaced is going to be a pain.

They have been in the boat for thirteen years. And the boat gets used at least for three weeks a year on long trips.

I have used spray on adhesives
with okay results. Waterproof contact cements work very good. It makes for a fast and very secure bond. Epoxy is the strongest adhesive I have used but takes over night to cure and the material needs to be held firmly in place while the epoxy sets. On the other hand, the stronger an adhesive bonds, the harder it will be to remove in the future.

Barge Cement
Barge works well, I’ve used it successfully for a number of years in Kevlar and on fiberglass. The important thing to remember is to clean the surface of the boat where you intend to glue the minicell with a solvent first. You can find Barge Cement in most hardware stores.


It’s coming along!
You guys are awsome! So many great ideas! I’m still fine tuning the seat. I had to laminate 4 pieces together. I used Weldwood contact cement. Really bonded good! I’m making the seat much longer than it was, and higher under the thighes. (Sleeping leg thing) I might use heavy duty velcro to fasten seat to the boat. You guys got me thinking about what if: …what if I needed to do a hull repair under the seat? If the seat is glued in place, that would mean trashing the whole thing to make a glass/kevlar repair. I had some velcro in another boat one time, and as somebody said, water does it’s thing and it came loose. The velcro I used had it’s own glue on one side. I think if I used some lexal or some type of silicon caulk that would hold the velcro in place much better.

Say, where’s a good place to get some neoprene if I want to cover this thing when I’m done?

Thanks to everybody that responded, to my post.

agongos-> Paul Lueders Lac du Flambeau, WI.

Double sided carpet tape can help
If you want to experiment before you make things permanent, double sided carpet tape can work well and is easily removed. I’ve used this for some thigh pads in my Hurricane Tracer and have had no problems.

David Cole

Epoxy for filing gaps
It’ll work great for filling gaps if you make “dookie schmutz” out of it: mix with wood flour.

I wouldn’t use epoxy for glueing minicell to glass, though. It’s a pain to remove.

does your QCC have glassed in hip braces? On all the kayaks I’ve made minicell seats for there were hip braces that I’d notch the seat sides for then put in Salamander hip pads to hold it down firmly. has neoprene foam for just that purpose… as a final cover over seats, etc.

very fast means of carving a seat
I use an abrasive wheel for fast carving of seats out of a block of minicell. Used on edge, the round wheel shape approximates the cross section of your thighs and bottom. Makes it very easy and very fast to carve a ‘tractor seat’ into minicell.

Just be careful, it can tear through minicell too quickly if you are not steady.

See the following link for something similar to what I have used…the wheel I found is readily available at Home Depot, is black and slightly less aggressive looking than this:

Thanks Bullseye, I’m gonna pick one up
in the morning. I’ve been using a 1/4" x 4" carborundum blade on my angle grinder and she bits too quick! Your suggestion looks like it might offer some easier control when getting close to the finish piece.

by hand
I’ve done ok making 3/8" deep hash marks with utility knife, followed by hand held 3" hole saw, followed by heavy/medium grit sanding disc hand held. I’m not too good keeping a power disc from grabbing.

The difference is…
…the solvent based products (contact cement, Lexel, etc.) can be removed with lacquer thinner or similar solvents without damaging the hull. Epoxy would have to be scraped/sanded off. I can’t think of a single good reason to use epoxy for installing a kayak seat.

instead of a tether
block it in so it absolutely can’t move. A half cubic foot of minicell has lots of flotation and the last thing you need is a loose seat during rescues.

Why remove the pads?
Unless they’re really damaged or coming loose, you can just take a Surform tool or coarse sandpaper to the surface to smooth it out, then glue on another layer of foam.