Thigh pad - adhesive and lining

I saw a version of this question from 2005, but wanted to ask again to see if things have changed since then.

I have a plastic kayak I bought used and need to glue the thigh pads back in. The pads are foam, but I don’t know what kind and there is some plastic lining on the side of the pads where they attached to the hull.

Q1 - Should I keep the plastic on or take it off?

Q2 - What kind of adhesive should I use to glue the pads to the hull? Weldwood? Goop?

Weldwood contact cement is the standard
But I think the goop would do as well. I start with craft spray adhesive for the first test paddles. then when I think it is OK I spray 3M super 77 spray adhesive and do a few long paddles. Once placement is just right, I use contact cement.

Re: More
Thanks that’s helpful. Interesting start with a basic adhesive and keep scaling up to contact cement. Any advice on whether I should keep the plastic lining on the pads?

Plastic lining
The plastic lining is part of the ‘peel and stick’ adhesive that was originally used to adhere the pads to the kayak plastic. You will probably regret attempting to remove it, as it will probably pull bits of foam with it, if you try.

If you can see the original placement of the pads I would make sure to remove as much sand and grit from the boat and pad, and replace them in their original position using the Weldwood in the red can, following the directions. Done properly you won’t be needing to do that particular task again.

I’ve done this on a couple white water boats I acquired used.

You can take the glue residue off
I agree that the “lining” is probably the glue residue from the peel and stick adhesive. That stuff always works for a while, then lets go.

Although you might be able to get a bond with contact cement without removing it, your chances are better if you do. I have been able to do so by simply sanding it off using a fairly coarse sandpaper.

If you know where you want the pads to go, hold them in place and mark around the margins with a Sharpie. You probably only need one coat of contact cement on the plastic hull, but use at least two, if not three on the foam. Make sure you use the flammable DAP Weldwood contact cement in the red and black can, not the non-flammable stuff in the green and black can. Other adhesives will work as well.