: Well, multiple reasons for this choice
: 1. Aluminum corrodes.
: 2. Graphite flexes to fit the curve.
: 3. Strength to weight ratio.
: 4. Aluminum is bulkier. I can use a much smaller diameter graphite tube.
: 5. Graphite will not kink or dent under stress like aluminum will. (of course
: it has its limits and will break, but not as easily as aluminum will bend
: or dent.)

: "Let me know if you disagree".

Hi Malcolm,

I disagree.

I think it's great that you want to try graphite tubes for your folder.

Since I have no experience with graphite stringers, I'm not qualified to
discuss their use. However, I believe you are operating under some
misconceptions regarding aluminum tubing, so I feel it's appropriate to
comment on your points above.

1. "Corrosion" -

Not a problem if you wax and rinse them off regurally. Just clean them up
every time you break-down the kayak. I paddle mostly fresh water, so once or
twice a year is enough for me. I've spent several days at a time paddling salt
water while on vacation, and a good rinsing after ruturning home is enough.
With a non-folder, aluminum could be a problem to maintain, but since a folder
dis-assembles, you will always have ready access to the tubes for maintenance

2. "Graphite Flexes to fit the curve". -

So does aluminum. The only mechanical bending on my kayaks is the keel to
stem / stern transitions. The rocker, sheer curve, gunwale, and chine bends
are all natural flexing of the tubes. They go straight when removed. Symetrik
has 3.5" rocker, with even greater sheer curve. My Aleuts have even greater
rocker, up to 5 inches.

3. "Strength to weight Ratio" - My frames have never failed, and they are up
to 17.5 feet long and weight as little 20 lbs with cross sections, footbrace,
and coaming, minus the skin.

4. "Aluminum is bulkier" -

I don't think that a 3/4" tube constituted bulk.

5. " Graphite will not kink or dent under stress like aluminum" -

I've built about 10 aluminum framed kayaks, both folding and non-folding, and
can't find a single kink or dent in any of them. I've never heard of
commercial Feathercraft kinking or denting with use, and they've been around
for a long time. If, in the event you damage a tube section, replacement
is simple since you can get to the damaged part so easily. Since you built the
boat in the first place, repair is a snap.

Light weight and shipping damage -

My 17.5 ft. folders average about 32 lbs. How much lighter should they be ?
Many are shipped in a plastidc golf travel case that is about 50 inches long.
I see no way that the tubes can be damaged in this case, any more than the golf
golf clubs it was designed to hold. Even with a softbag, I've never experienced
any damage. My two Cannondale bikes are aluminum, and they certainly have been
durable.

One of aluminum's "strength's" is how easy it is to cut, drill, and rivet.
Plus, the tube ends can be easily shaped to permit a smooth tranistion at
the stems. Something to consider when choosing building materials.

Good luck with the graphite tubing. I look forward to hearing about your
experiences, both good and bad.

"Experience is knowledge. Everything else is just information".

Best Regards,

Tom