welding holes in your kayak

Are all kayaks made of the same plastic material? Lets say, I have a hole on my hobie, can I use plastic chunks taken from an ocean kayak or other brands?

Some manufacturers use different plastics. I don't know if they mix and match. I think plastic of the same type should be used, but what do I know? I'm a vacuum cleaner salesman.

If you buy a new kayak more times than not there will be some plastic shavings inside the hull.
Scoop them up and put them in a plastic bag for possible future use.
If you unscrew the pad eyes on your Hobie there will be shavings there as well.
If you ever drill a hole in your kayak save the plastic.
This way you will have the exact same plastic to fix a small hole.

Great tip Tote.

Medium density polyethylene.

If you buy a new kayak more times than not there will be some plastic shavings inside the hull.
Scoop them up and put them in a plastic bag for possible future use.
If you unscrew the pad eyes on your Hobie there will be shavings there as well.
If you ever drill a hole in your kayak save the plastic.
This way you will have the exact same plastic to fix a small hole.

+1
I kept the hole cutout when I drilled for the scotty flushmount in case I would need it someday.

Medium density polyethylene.

Why medium?  I thought kayaks were High Density.

-Allen

Medium density polyethylene.

Why medium?  I thought kayaks were High Density.
-Allen

Most of the time if you need some filler material to weld up a hole you can contact the manufacture and ask for some. Dealers might also have some laying around. And no not all kayaks are made of the same plastic. For instance cross link Poly kayaks can't be welded/repaired but I don't think it's been used in a few years.

Medium density polyethylene.

Why medium?  I thought kayaks were High Density.
-Allen

Well, I should have known that for OK.     That being said,  a lot of other kayaks are high density.  It's best to match the poly type to the specific yak.

-Allen

Wildy is HDPE as well as Hobie I believe.

http://en.wikipedia.org/wiki/Polyethylene

This is what Wilderness says: our “roto” kayaks are molded of Gen2, our proprietary super high density linear polyethylene, engineered to provide resilience, resistance to impact and abrasion, and to provide the stiffness necessary for efficient paddling.

Here is a guide on repairing a kayak: http://www.wildernesssystems.com/content/wildernesssystems.com/assets/page/polyethylene_plastic_repair_guide/Polyethylene_Repair_Guide.pdf

This also talks about different plastics.

   The higher the density the stiffer the hull, but the sacrifice ( trade off ) is it becomes more prone to cracks.     At least as far as the linear PE goes.    Not all the cracking issues are related to density though,  the design (shape) can put stress in areas that eventually break down and start to leak. 
   
     Almost any of the linear PE materials will work as long as they are roto molded grade, not an injection mold type.  ( plastic buckets are injection molded PE or Polypro. )
   
     So, yeah, save those pieces you cut out when making modifications... it helps.     It's often easy to shave off material around the hatches...

   The purpose of this video was to show you guys how easy it is to make repairs yourself.    I've seen repairs with solder irons and torches in the past,,, they were'n't pretty.      If you have enough extra material to fill a hole,, you can really build up  the thickness then sand and shape it to a fairly smooth finish.