What Paddle Would You Build?

[blackeye]

In honour of and respect for Bigreen's "what would you shape" thread, we need the same thing for paddles.  We haven't had a good paddle build thread for a while.

Sometime, when there is time, I'm going to make my second paddle, maybe even attempt a shaft.  My first was E-glass over XPS and cedar and weighs 1013g.  Its very stiff so a bit overbuilt.  

1) Can anyone shed light on roughly how many layers of carbon or glass one has to wrap to make a not-too-delicate shaft?  
2) How does one get the set laminate off the mandrel?  
3) Would a laminate over a foam core for the shaft work?  I figure let it cure in a length of angle iron so it stays true.  

So lets hear it from the pros, the experienced guys, the bodgers (me), and the dreamers (me again).  All are welcome here.  

[Wood_Ogre]

1013 grams =35.73 oz. You need to get it down to the low or mid 20s. Congrats on your 1st paddle ! You only got another 50 or so to go until you get the hang of it. I would love to see a picture !

[Celeste]

wrap the mandrel in polyethylene sheeting, epoxy does not stick to it and it is slippery, you can slide the mandrel out, then pull the poly out.  Use heat shrink tubing to compress the assembly, it will keep the weight down by reducing the amount of epoxy on the shaft.  They make specially treated heat shrink for just this purpose. 

Use the mandrel to hang it vertically to keep it straight

I will say this just in case you don't know it, use braided tubes, don't try to wrap flat cloth.  The tubes come in both unidirectional and bias.  the diameter of the bias is adjusted by shorting or lengthening it axially, shorten it it gets bigger in diameter, pull it longer it gets smaller.  the uni you adjust by twisting it axially, making it smaller by making the fibers a helix.

As for how many layers, that will depend on the materials you use.  Uni has a lot of axial stiffness but has little radial crush strength, so will need at least one layer bias if it is going to survive for long.

[DurhamSUP]

Excellent question. I have been wondering the same. I know I'll never make a better paddle than a QB, Ke Nalu, Kialoa, or Werner, but it is fun to mess around making stuff.

There was some really great info here:
http://www.standupzone.com/forum/index.php?topic=18897.0

I think he mentioned that you need about 26oz of carbon and about a 3rd more for glass on the shaft.


but I am curious of other methods for the back yard hack (me).

I can tell you what not to do.... I wrapped a PVC pipe with plastic and rolled 6 layers of of 6oz glass on it. I guess I used too much plastic. When I tried to pull the pipe out, the plastic got bound up an I could never get the pipe out. I ended up cutting the tube to get it out. Then I wrapped it with more glass. The paddle ended up at 32oz and broke the first time out.

I'm going to try some wax on the pipe next and see what happens.

[supthecreek]

how about this approach....

Find a commercially available shaft you like (I know Ke Nalu sells components)

Then:
make your own custom blades and handles to fit the shaft and use Hot Glue to interchange.
Lots of variety and experimentation with less hassle and expense.

Hey... I like that idea... I may make a blade

[blackeye]

Use heat shrink tubing to compress the assembly...They make specially treated heat shrink for just this purpose. 

Use the mandrel to hang it vertically to keep it straight

I will say this just in case you don't know it, use braided tubes, don't try to wrap flat cloth. 

Didn't know about the heat shrink - instead of vacuuming.  Does one use film and a bleed layer underneath the heat shrink?

The hanging mandrel is a great idea too.

I just heard about these tubes the night before the post.  I hear they are like a big Chinese finger trap. I haven't seen them at the local supplier, but I'll look harder online.  Why not wrap cloth?

DurhamSUP - that thread and others by NLC Hawaii was awesome.  There are some earlier ones that are good too.  Every time I re-read them I pick up something new. 

supthecreek - I just do stuff the most awkward way possible, so buying a shaft is out of the question.  Go for the blade job - I formed mine on a piece of plexi-glass clamped over a wood frame.  The frame was just four pieces of 2x4 clamped to my workmate.  That gave the plexi the curve I wanted in the blade. 

Wood_Ogre - this is my second season with that paddle and it has stood up to the off-the-water abuse pretty well.  In my eagerness to use it I never did the final finishing.  I should sand it down and re-hotcoat it.  Also, the painting is a bit garish so I want to get rid of that before I show it to the zone.  Interestingly, the Silvertip Laminating Resin was incompatible with some of the paint I used and it formed a lattice like pattern in those areas. 

[Bean]

Soller Composites www.sollercomposites.com has a great selection of carbon tube and shrink tube.  They also have a nice tutorial. 

[supthecreek]

A friend of mine made a paddle shaft from left over lengths of stock used to make the outriggers on sport fishing boats.
A little heavy, but free carbon fiber shafts

[Ucycle]

wrapping cloth is pretty hard for 60"tube, i tried to roll a single sheet of cf on to a pvc pipe(2ft) and it was really hard to get it tight and hours of hammering time to get the pvc pipe off(even with a layer of wax paper on it).  
i would first try it with fiberglass and whatever mold material/demolding method you want to use and see how hard to remove the mold.  If you can remove it, you dont lose much $ like CF.  Some people make the mold with a slight taper to one end so it slide of super easy.  Also some use alu mold so when they cure it in a hot box, the alu will expand and compress the fiber and when it cools, it will shrink and unmold by itself.  the alu mold can be cheap if you want a round shaft but any other shape its going be expensive.
The amount of layers of cf/fiberglass and fiber orientation(very important, flex/stiffness) is like a secret recipe, nobody is going to tell you how many layers and fiber orientation.  If you have a good paddle you like and dont mind cutting a small section out, you can measure the thickness and do step sanding to get the fiber orientation and copy it.

Also try to use uni carbon for the majority of the paddle, that where you fine tune the stiffness by orientating the uni carbon in a specific direction to minimize the twist of the blade and make it stiff but yet flexible enough to not hurt your shoulder.  also like what NLS said about the cf sleeves, they are easy to make a cf tube with it but you can't change the fiber orientation. the orientation of the fiber is going to be base on the sleeve size and the mold you are using on and you are stuck with that orientation for that whole paddle.

you can see how complicate and time consuming it is to make a paddle, alot of testing and $ to get it right.   Many of the paddle makers spend couple years to fine tune their paddle before it becomes a production paddle.  That is why i never venture to composite paddle making, its complicate to make a good one off paddle.  

[Bean]

If you want a specific taper, or a one-off, you could also shape the shaft in foam then disolve it after the CF cures.

[blackeye]

If you want a specific taper, or a one-off, you could also shape the shaft in foam then disolve it after the CF cures.

Why not just leave the foam in situ?  I thinking the answer is that it will be too stiff.  Using foam one could get all sorts of fancy shapes. 

All great advice.  Maybe I'll stick with cedar shafts. 

[PonoBill]

If you do a tapered mandrel then as soon as you shift it a little tiny bit, it's loose. But that little bit can be a challenge. You can make a mandrel and saw it vertically into 4 segments, then build up in between the segments with layers of waxed paper. somehow keep it all together, then wind your glass and carbon on. Whack one segment free and they all fall out. Or just buy a Ke Nalu shaft.

You can also make a shaft with one or two wraps of glass--impregnate it on a table and scrape out the epoxy. Let it kick, then slit lengthwise to release the shaft from the mandrel. Now wrap the hollow glass tube with uni, twill, or tow carbon. paint on the epoxy, and wrap tightly with mylar tape--otherwise known as old VCR tapes. pull it tight as you wind and it squeezes out almost as much as an autoclave vacuum job.

The only way to make a great blade is in a heated aluminum mold, but that just my POV. Whittle one out of light wood and glass it. Handles--you can figure that out yourself.

[NLCHAWAII]

Hey Bill , your stuffs almost ready plus something extra , thx for being patient . What Bill and somebody earlier mentioned , a few wraps on the mandrel , let it kick and cure then cut a length wise seem to remove it and then tape and epoxy the seem back together . Let that cure rigid , then continue with your laminants . Unless your a full blown composite shop with near Military contract grade abilities , your never going to get all your shaft laminants done in one step . The structure of my shafts are on the short end four steps and sometimes stretch out to 6-7 steps before graphics and finish . At minimum you need a shaft wall build up of at least 24 oz. = 6 layers of 4 oz glass . 30 oz build up gets heavy , but somewhere in between is a sweet spot depending on your fiber to resin compaction ratio , shaft shape and size , etc . Then with those numbers you can start to play around with mixtures of different fibers such as carbon and glass . YOU WILL NEVER FIGURE ALL THIS OUT IN JUST ONE OR TWO BUILDS . A bathroom full of paddles later and you'll start to get a feel for what works and what doesn't . You'll spend approximately $15,000 less by starting off with a premade Kenalu shaft , but hey , if your up for the financial beating then ..... Gods speed to ya man . I use to make my own tuna lures and was always so proud of the fish I'd catch with my own hand made gear . But then again , those fish would bite a bear hook some days . The point is that going down a path and thru a process can be very gratifying and almost always beats not trying at all . Keep asking , and the community will keep sharing . Aloha - Ax - NLC

[PonoBill]

Ke Nalu shafts are made with on an aluminum mandrel with a shrink-wrap wind. It's a bitch of a process, but you wind up with a light, strong, consistent shaft. Even with a high-tech process sometimes it takes a BFH (Big F#*ing hammer) to get the mandrel out.

Making paddles isn't for sissies.

[NLCHAWAII]

Amen to what Bill said .... I used to have a system to yank the mandrel out at a certain point of resin cure . Common sense and My backyard gorilla style of construction has taught me that I don't like the feeling of the skin on my palms sliding off my hands at 150 F , followed by a month + of healing to do the next try . I can make shafts all day long with a smile by just cutting the darn things off the mandrel and saving my hands . Again , AMEN to what Bill just said ! and beyond all that and the incidental problems .... makin stuff is fun !