Get these two items:
Fixed Boat Hook 1.6m SKU: 9068N
www.whitworths.com.au/fixed-boat-hook-1-6m
$9.95
Standard Aluminium Paddle SKU: 55343
www.whitworths.com.au/standard-aluminium-palm-grip-paddle-1-2m
$15.95
Hacksaw the hook off the boat hook;
Hacksaw off the last part of the handle of the boat hook exposing access to the end of the aluminium tube;
Hacksaw the end of the blade of the paddle to make a straight, not a curved bottom end;
Drill out the pop rivet holding the handle in the end of the paddle;
Cut packing foam to block the ends of each of the two aluminium tubes;
I think that the foam may be called EVA foam, styrofoam is OK but make sure that the foam you use does not absorb water (like surfboard foam) and that the foam stops water from getting in the tubes
Stuff the foam a little way into the tubes;
(Now this is the hard bit)
Grind/sand/cut whatever, the diameter of the paddle end to go into the smaller diameter tube, at the end where the rubber is;
Secure the paddle end with a stainless self-tapping screw or an aluminium pop rivet;
Work out how long you want the paddle to be (don't cut anything);
Fit the two tubes together and slide the two to make the paddle the length you want;
Make sure you have the blade of the paddle and the direction of the handle in the right place then,
Drill a hole for either a pop rivet or a stainless self-tapping screw.
For good measure tape up the join at the handle and in the two tubes to make this water-tight.
Congratulations, you have a SUP paddle for $25.90
hey thats not too bad!
Also too save more money on a board you could just chop a 44 gallon drum in half long ways, pop rivet them together end to end and have an awesome wave board to go with the new paddle! could even add more half drums if you wanted to do more open ocean racing! 3 or 4 drums should make a 12' BOP board! easy!!! 
come on boys. it might be all some people can afford especially if you have to out fit the whole tribe
hmmm, half forty four gallon drums hey - fast shape
Or just to Mitre 10 and by three pieces of Miranti and some balsa. Use your imagination, some cloth and epoxy resin and you have a good paddle for under $25. Kind of fun to make as well!
just wait till it catches on with the like of Starboard and Naish
Brilliant stuff Makesurf.
Obviously not the paddle of choice for the 'elite' amongst us but what a great way to keep the kids and friends involved at a low cost.
How durable are they?
How is the patent going
Great DIY project Makesurf,
Did a similar thing but just put in a longer length of the orginal size tube between paddle blade and handle for my 3 kids when they started out.
The same 3 paddles are in the shed 4 years down the track and get used by other kids these days.
Pretty indestructable really and dirt cheep.
You can use self amalgamating heat shrink to seal the joints and wall filling spray in foam to fill the tubes so it floats.
Great post.
Phill
Not bad. But your paddle is straight! (no forward pitch)
An even cheaper, extremely cunning and maybe better method is this.
1. -Get the cheapy blade as you describe.
2. (Cunning part)
from a broken windsurfing boom, salvage the "good" boom arm.
(you may get one for free from a windsurfing shop...
...maybe even a carbon one)
* The straight section of the boom arm will be the shaft of the paddle, but hacksaw the boom just after it starts to curve at the front.
(now when you attach your cheapy blade to this point it will have a slight forward pitch like a real sup paddle)
At the rear end of the boom, insert the boom's tail pipe. (single pipe only, of course) and add the palm cap as you described, at the correct angle to line up with the blade.
You now have an adjustable paddle, with a forward pitch on the blade and a rubber grip on the shaft that will stop the rails of your board from getting scratched up.
(ie no need for rail tape!)
QED
Seriously for $20 and a little bit of resin you can make a light paddle that floats, has an acceptable design and works well. The first paddle I made I used a few bits of Miranti from Mitre 10 which is the type they use for door jams etc.
Make a clamping block for the paddle end at 10 degrees bend. use Epoxy resin and some fibreglass scrap from any surfboard factory bin and clamp the rectangles along it's length and over the block to give the paddle end the bend.
Use a planer, wood rasp or whatever depending upon your level of roughness to taper and round the shaft. Rectangles make ovals when round, squares make circles....
Get some surfboard foam or balsa and glue it the end of the bent shaft. Cut it out, shape it so it looks like a paddle. Do the same with the palm grip.
Basic tools, small cost and you get to feel like you've done something. I made this paddle years ago and it's still in the garage as a spare, I've made a few since then as well using more exotic materials...
