[HELP REPAIR] - Hobie Kayak hole can it be fixed?

If that is the rear, then the rudder system is gone and probably toast as well.  Also, that's a 2005 or so year Outback from the look of it.  Prone to other issues as well, other than the gaping hole.   

It's only 9 or 10 feet long its small for me being 6ft and 250lbs :/

Found this http://www.urethanesupply.com/kcwelder.php

Looks legit

I tried welding a battery. Looked great for few days till i saw acid on the wood the bat was sitting on. Good luck. Wear a pfd.

     Good advice Abdiver gave.        I had one slip half out of my trailer once, it sustained the same damage.   Took several hours , but  it's good as new,, maybe a little  thicker now than before.         I raced it at the PIF that day...
   I use a hot air welder

We just had a demo on a hot air welder, nitrogen cooled. Urethane Supply Systems. Expensive but a way cool welder.

I have another sugestion,maybe easier than welding. Many kayaks have removeable wear plates in the bow and stern. Make one out of a solid chunk of poly or ABS,shape as desired,cut the boat for a tight fit and silicone the crap out of it and screw in place. You may end up with an upgrade that can be replaced.

      Silicone will never work ...    peels right off PE material.    try goop. 

  But then again,,,    It's a worn out plastic boat  Discard the thing.  It's  DOA

Here you go.

 

  If it's not free, I wouldn't bother!  Seems like way too much work.

Anyone got an old beater kayak they'd like to donate to the cause?  I'd like to put a bunch of holes in it and repair them in various ways to compare and contrast.  Let's settle it!!!

-Allen

VIDEO-Kayak Keel Repair - Wilderness Systems Ride 135

IMO- Heat gun welding is more of a surface weld and not necessarily a full penetration weld like you get with a typically plastic welder. The heat gun heats the two materials and they may stick to one another but the plastic is not blended together creating a single material.It may work in the beginning but over time will most likely crack and pull apart at the seam from what I have experenced with other peoples repairs. Small pin holes its fine but cracks or larger repairs =no bueno. Remember if done correctly a weld should be stronger than the surrounding area.....in plastic or in metal. Also a plastic welder turns out a much nicer and far superior finished product. This based on repairing all types of applications like bumbers, motorcycle plastics, kayaks, ETC.

The wood dowel recommendation in the video is not necessary for support even in the keel if the two materials are blended. The material you are replacing should be of equal thickness + of the existing. If additional thickness is desired for future wear then more material can be added but it will be as strong if not stronger when finished.

As an example here is a keel and scupper repair I completed a couple years ago on a kayak.

Nothing will stick to MDPE but other polyethelyene

Nothing will stick to MDPE but other polyethelyene

+1

It's only 9 or 10 feet long its small for me being 6ft and 250lbs :/

Sounds like a sport... @ 250lbs you are already exceeding it's capacity as per the manufacturer.  That makes it a total no go IMO... repaired or not.

Hobie Mirage Sport:

    Crew: 1
    Length: 9' 7" / 2.92 m
    Width: 29.5" / .75 m
    Capacity: 225 lbs / 102 kg
    Fitted Hull Weight: 53 lbs / 24.04 kg
    Fully Rigged Weight: 66.3 lbs / 30.07 kg
    Hull Construction: Rotomolded Polyethylene

My hobbie was bought used, and it has a fair amount of wear in that area as well. I have JB welded it on the outside and then gooped the snot out of it on the inside.   Haven't had a problem sice.  I am not sure if a fiberglass bond body repair kit would adhere to the plastic in question.  Spray foam insulation would not hurt either, once it is all completed.  I have seen far worse on fiberglass boats that kept on ticking.