Modifying kayak seat with heat gun?

-- Last Updated: Apr-26-11 2:51 PM EST --

Hi guys,

A bit new to kayaking and new here as well...

Have a question:

First a bit of background...
Was just given a used Current Designs Extreme kayak.. It's a bit rough and I'm going to basically restore it. The top side needs some serious rubbing compound and maybe a bit of wet sanding, and the bottom needs some gel coat repair.

The kayak itself is a bit of a more advanced model than I'm really ready for, but given it was a gift and the fact that I'm on a serious budget, I'm will to make some adjustments, repairs and grow into it.

Now for the question..
The cockpit in this particular unit is 15.5" wide. I have a 38-40" waist and the seat is a bit tight in my upper thigh/lower hip area. I can stand to lose a bit of weight and I'm sure that would help, but I was wondering if I were careful, how successful you experts think I might be by gently heating (what appears to be ABS) the sides of the seat with a heat gun and pushing them out a bit to give myself another half an inch or so on each side...

Thoughts?

I've seen lots of stuff out there on seat replacement and carving seats out of foam.. This particular model has the seat riveted to a down extension coming off the coaming and has a fiberglass support that comes up from the bottom to meet at this riveted section.. I'm assuming this is common on Current Designs models. Has anyone out there had luck replacing CD kayak seats?

Much appreciation for any wisdom provided!

jbmia

CD parts
CD offers a wide seat pan - it was included on the Pachena (I have one) and on the other big boy boats (Solstice Titan, etc.). You could give them a call and see if they’ll sell you one to retrofit, but it probably won’t be cheap. It may need a larger coaming to work properly, but they would be able to tell you. It’s a comfortable seat, BTW.



I don’t know about heating ABS and reforming it. Someone here at p-net cut holes out of the risers on either side of a narrow seat to get a little room for his bony hips. It sounds like it worked OK - maybe that’s an option.

Make sure the seat is ABS
I don’t think I have ever seen one.



My seat that I ripped out of the CD Caribou had the same risers. I did not do a material test but think it was fiberglass. That would not have been pretty to melt



Just a saw and sandpaper to get it out.



And new shaped foam.



Yes I know that ski boots are molded with heat but are you really going to sit on a hot seat with imperfect temperature control?

Thanks for the replies guys…
I took a closer look at the seat and popped a few pics… based on the comment above, I had to double check as I more just kind of assumed and didn’t really feel under or behind the seat for a fiberglass texture…



At any rate, it does appears to be some type of plastic… I’m assuming ABS… note the pics of the top side of the seat…note the thin material… on feeling under the seat, it doesn’t have that glass texture… just feels like plastic…



What I was thinking of doing, was getting some sort of protective material and putting it between the seat and the fiberglass body of the interior of the kayak and gently heat it up in the affected area… I was then thinking of maybe duct taping a pot holder or something on each side of my legs (in advance of course) and then jumping in while the plastic was heated up… then maybe hanging out and reading the funny papers for a while… :wink:



Here’s a link to the pics:

https://picasaweb.google.com/102825745327166232873/RecentlyUpdated#



jbmia

CD seat
your kayak has fiberglass seat posts that go from the top deck at the cockpit rim to the hull to do what you are thinking, to get the extra room you need to cut the post out shorten them then epoxy and glass them back in about 1/2" to 3/4" on each side then bolt or pop rivet the seat back in.

There you go…
Sounds a bit more involved, but also sounds like the real solution. I’ve sprayed gel coat, but I’ve never laid fiberglass before. I’m not in a rush, so I’ll have to think that one through a bit and do some research…



Off the cuff though, I guess the first thing I was thinking was how I would I reattach the new glass to the old top and bottom… Will it create a strong bond by touch alone once cured or should there be some mechanical attachment?



Seems like I might need some sort of jig or template I could lay it on and then remove once it cures…



Any tips there?



Thanks for all the input guys…

It does…
It does look like some sort of thermoformed plastic.



So yes, it would be possible to re-form it by heating.



I would not go for your potholder idea.



The problem with using a heat gun is that the transition from hot enough to form to way to hot and droopy can happen very fast.



Heat slowly. Test often. Have a bunch of cold wet towels ready.

CD seat
The problem with trying to make the seat wider at the thigh bone is you can only heat the forward edge of the seat you legs will still hurt, because the seat post will not let it go wide enough.

If you cut the seat post loose you’ll have to fiberglass it back in after you cut it loose at the top and bottom with epoxy and cloth, I clamp a spacer at the top that gives me a edge to place the seat post at the top and hold it at 90 deg. to the deck and place some thicken epoxy at the top and bottom, when that drys I epoxy in cloth on both ends. When that curs I bolt or pop rivet the seat back in and force it wider, if that isn’t wide enough I install a wide base seat from CD.

Problems with the heating
I second Mintjulip’s comment on the transition between getting the plastic moldable and turning it into soup. The entire area has to be heated uniformly and slowly, and if it is anything like the royalex I tried to work with, there isn’t much room for error. Moldable and dripping states are only about ten or twenty degrees apart.



This problem is compounded because don’t you need to do both sides of the seat at the same time? And isn’t the part you want to heat and mold the part that supports the seat you are going to sit on with your pot holder lined thighs? If it is soft enough to bend, won’t it stretch to the bottom of the hull?



If you try it, post back with your results. You might teach me something. But, I think you will be better off with mechanical rearrangements, such as tearing the whole thing out and dropping in a shaped, foam seat.



Wasn’t there somebody that used that expandable, spray-in, construction, insulation foam, while sitting in the boat, to make a seat? I hear that stuff gets hot as it cures, and I can testify that it expands. You might try a search to find info on that approach to custom fitting the boat to your body shape.



Good luck with the project.

~~Chip

You sound like you’ve done this…
… a few times. I’m trying to visualize what this would look like… By any chance would you have a pic or two of the results? I think that would help me understand a bit better…



Couple additional questions…


  • Do you cut, up toward the coaming, above the screw that holds the strap to the back of the pillar? Or, do you cut below that screw and leave more of the pillar intact.



    -How far up from the base of the kayak do you cut the pillar coming up off the bottom?


  • I’m assuming that the 90 degree angle is placed behind whats left of the pillar. In practice, does that create any discomfort with what effectively results in a hard 90 degree angle facing into the seat? (Unless I’m understanding this wrong…) With that in mind, I suppose a smoother transition could be fabricated on the seat side…



    Thanks for your insight!



    jbmia

Thanks for all the input so far…
Much appreciation for the wisdom…



jbmia


My experience with CD
is that they have zero customer service

minicell
Just cut out the whole seat, posts and all and put in a minicell seat carved to fit your body. Easy and comfortable. Lots of us have done this on a variety of boats.

and the winner is $$$$$$$$$$

– Last Updated: Apr-27-11 7:06 PM EST –

Best Answer. Just take the seat out and replace with minicell.

It would not hurt to try heating and pushing and molding the plastic. I doubt it will work well, and it looks like the supports actually are what are hitting your hips and upper thighs.

It might be easier to give up burgers, fries, and sodas for a couple of months. When your butt won't fit in a kayak - it's time to think about what that means.

foam seat - $45

– Last Updated: Apr-27-11 7:05 PM EST –

Actually, only $40.

http://shop.skinboats.com/product.sc?categoryId=2&productId=2

By the way, I think I might be the guy who cut out windows in the side of the seat to accommodate my wide hips, but it wasn't that much of an improvement. Shortly after that, I cut out the whole thing, and put in a foam seat.