trying to find a way to stick my under deck bag (velcro attachments) into my poly boat. i’ve used contact cement on adhesive backed 2" hook and loop to permanently bond the velcro into my glass boat.
i’m told this won’t work on the poly boat. any suggestions?
Contact Cement worked for me
I have used plain old contact cement to attach closed cell foam on both my poly kayaks. One has been on for over a year and is still solid. You might want to give it a try, it’s cheap and can be cleaned off with out too much trouble if it does come loose.
guess i’ll try
the contact cement route first. thanks Mike for your obviously very knowledgeable take on the 3 M product. i’ve used 3532 Urethane stuff before and it is incredible but impossible to find and super expensive. well beyond what i am hoping to achieve. some of these glues are so industrial specific (spoke with 3M direct and they said much of the urethane structural adhesives are used in avaition) that they just can’t be found outside of full case loads by special order.
any other ideas floating around out there? no more nails or something?
shoe goo
I have used shoe goo to glue things to my poly kayak. Has held up really well so far.
Try "no more nails"
Or similar.
find some vinyl or rubber backed d-rings
and attach them with contact cement. Clean with alcohol, rough up with 80grit, apply a few coats of contact cement to d-ring backing (approx 1 1/2" diameter) and press together when DRY. It’ll stay on. I’ve got some on the bottom of my plastic Chatham16 right in front of the seat. It’s attached.
Contact cement won’t work long-term
– Last Updated: Sep-01-06 11:26 AM EST –
Neither will anything else if the attachments are under tension (with the possible exception of the 3M Scotch-Weld DP-8005). That's why boat manufacturers use screws or rivets for most attachments on plastic boats.
surface area/load
I wonder. Gluing on velcro seems to be hopeless as there’s always a concentration of load in one part of the glued on velcro that rips it up. On the other hand I’ve had minicell stay in with no problem for years. Methinks the problem is that there’s a low maximum psi that can’t be exceeded.
I’ll see how these glued on d-ring straps hold up. So far it’s solid.
really Lee?
i didn’t think vinyl backed d rings would stick to poly. should i use contact cement or Vinyl tec 2000 type cement. i also have some stuff called Pliobond which i used for the glass boats…
thanks again for all the advice and thoughts.
i learn much here, which is why i keep posting!
I glued on some
pricey rubber backed d-rings used on zodiac boats onto the inside of my plastic Chatham and they’re ATTACHED. Then got some cheap vinyl ones(coated nylon?)with webbing sewn over the ss d-ring that I have yet to use. I could be all wrong but my experience has been that if the glued on thing thing doesn’t get regular tugging like velcro things hold on as long as the plastic is well roughed up before glueing and the area is large. You might fuzz it then pass a flame over it quickly to make the plastic stickier to the glue.
this makes me wonder a qvestion!
yes, a gvestion! 
if we buy some of the plastic kayaks, I wonder if you can put any stickers on them, without worries of breaking down the hull where it’s stuck to?
it’s a concern for bicycle helmets, so immediately my caution is up…but when we get our boats, we’d love to put the names we call each other on the bow’s.
I ask about the stickers because I think an iron on is too far out! 
don’t worry about stickers
The thickness of the PE is far more than the thin shell of a bike helmet. I still have stickers on a ten year old poly hull and there’s been no issues other than it peeling and fading in the UV. I’ve used Devcon Plumbers Goop or Marine Goop with great success on PE boats as long as everything is really clean. REALLY clean since if there is any sand or grit between the two glued items it forms micro air pockets and leaves less adhesion surface. Wow…that sounded really engineer like but I’m as far from being mechanical as you can get! An under deck bag that carries a lot of weight (quart water etc)would best be served IMO with rivets for the attaching pads on a poly boat. I have one on a glass kayak and love it but you need to be sure you’ve got the deck height.
Polyurethane adhesive /caulk
Readily available at HD or Lowes but it takes a week to dry. Used it to mount a transducer in a plastic fishing kayak. Held for 3 years when I sold the boat. May still be holding.
Velcro and Minicel
I agree about Velcro. In fact, the hook side of Velcro is polyethylene or something similar and glue doesn’t stick to it any better than it does to a plastic hull. The loop side is Nylon pile or similar and glue bonds to it well.
As for Minicel, do you have any foam parts that are under tension? Typically, pads are under compression most of the time, so there is no reason for them to come loose. A foam pump holder isn’t under enough load for it to be a problem. What other Minicel parts do you have in your boat(s)?
Polyethylene is very chemical resistant
That’s why poly containers are often used to store solvents. Poly boats can become stained, but there’s no chemical that I know of that will dissolve/soften a poly hull or make it weark or brittle. Heat and abrasion are the biggest enemies of polyethylene, followed by UV exposure.
…Polye…That different from Royalex?
– Last Updated: Sep-02-06 9:32 PM EST –
Hi jbv,
..MikeM & others' experience-->probably much more than me...if the mixture-compounds' mat. are safe for Polyeth?.. procedure sounds fine, otherwise, my tutoring & usage on Royalex(w/both Vinyl-Tec2000 & Weldwood Contact) is to clean off, apply(to both sides)..letting the MEK dry out(20min), re-apply...let dry again, reheat with hair dryer...then join. It's the MEK that eats thru Royalex...Polye..?? Maybe 10:1 mixtures(etc) work without need for timed drying...??
$.01...
Steve
poly vs royalex
poly is polyethylene, royalex is abs sandwiched by vinyl on either side.
the adhesive you are using is made for bonding to vinyl.
i will check into poly specific formulations, thanks for the tips.