Re: Sanding / cutting the battered edges of a carbon paddle

Apart from the paddling aspect, frayed blades are not pleasant for another reason.

Some time ago, I was paddling with my 5 year old blade - which had badly chipped and frayed edges. Coming in through surf I fell off, held onto my paddle, realised I would damage either it or the ski to which it was leashed and let go of it.

The paddle blade pulled across my thumb and left it with a cut that looked as though a rotary saw had gone through it... and I was left in the break in Fish Hoek during sharky season chumming the water like a pro. Never seen myself swim so fast...

I bought a new paddle - but I'd also be interested in replies to Martin's question.

Hey guys ....... this is pulled from our website ........ www.eteamz.com/paddleshop

A good gelcoat touch up article in there too.

Below is the build up way if compelled to do all the steps.........

........If not, rinse w/fresh, dry out, tape and token wet out the frayed tips with some thickend epoxy ...... jam it in all the nooks you can. You are trying to 'save' some of the rotted stuff to keep paddle profile intact as much as poss. Clean up any mess before it hardens ...... let the tips go off. O.k. to use just about anything you feel handy with. Some 150 on a block would be fast and safe for shaping, finish with 320 o.k. .....do it again if you want too.

If I had to build up the perimeter of a THIN LAMINATE blade.....

......and have it come out nice: (A thicker wood blade would be slightly different)

Do one side at a time....

Mask area to be built up 1/4" inch back from edge.

Sand to tape for prep. Do both sides of paddle at this time.

Pull masking tape and retape w/ fresh again at 1/4" line. Also place another layer of tape over this one at 1/8" or half the distance of first one to edge..... do above 1/4" & 1/8" on one side only....

Mask 'backside' of repair to over hang 1/4"+ out away from edge.... creating a dam so to speak.

Important!> Make sure the dam comes STRAIGHT OUT from edge and does not curve towards or away from area being built up. This is one reason to not have tape come out more than 1/4" or so from edge.. no worries on straight runs but doing the curved tips will cause tape to want to curl....Use more (pieces) tape if you want to do more than 1/4" or so.. Really press the tape down around any chips or chunks you are trying to fill in too. If chunk is ragged , sand edges smooth and even bevel it a bit on both sides for more mechanical grip.

A smart thing to do with tape in hand here is to mask w/ paper the rest of paddle now. Shaft too.

Use Uni carbon or glass, forget kevlar, not worth the trouble........ note; to 'make' your own uni, buy some cloth which is more useful for other projects and just pull a few long bundles out of it, viola ! Uni.

Wet out with Epoxy and lay onto sanded-taped-masked-horizontally sitting blade. If you have to, place shaft LIGHTLY in a vice to achieve best compromise of levelness. Do not use too much resin. Experiment on table first to see how much is needed....place wet out long strands ( wet out on table first) into position & poke it into position just along the 1/8" tape line and hanging off the edge.

Gently work out as much resin as poss and still keep strands in place with the 1/8" tape line just showing. (This is the best reason to play with some on the table first.... told you so already.)

Once it is not so juicy , pull 1/8" tape.

Smooth out biasing strands and excess resin towards edge by laying some wrinkle free 4 mil plastic down over strands starting at 1/4" tape line and moving outward. Should have a tiny bit of resin 'backfill' to tape 1/4" tape line but strands stay in place at 1/8".
Let cure before pulling plastic.

Pull all tape including backside and repeat above on other side..... lightly sanding for prep again if excess resin migrated under tape on what was the 'backside' initially.

If done right the only sanding ness on blade is a tiny bit from the thickness of the 1/4" tape line..... a good reason to use the best 3M Pinstripe tape + it will do the curves of the blades in a single piece.
Even this little line will probably be better than the jagged edge like before. Would be cool to add some pigment to resin for a colored edge look.
Sand 'new land' on outside edge of paddle to taste.... should be plenty there to file first followed up with 320/600 wet or dry.

Use in best of health and happiness.


aloha

Most paddles have all carbon blades with a foam core, but solid carbon around the edges. If you chip away too much carbon on the edge, you will reach the foam core (bad). Therefore, I would recommend that you do most of your sanding by hand rather than using power tools.

Some paddles have kevlar reinforcement on the tips. If this is the case, when you sand the edge of the blade, you will not end up with a smooth edge, but rather, bits of kevlar will still be there. This is easy to solve. After you have sanded the tip to as you want it (but ragged kevlar still remains), mix up some epoxy (preferably thin/runny expoxy--not the thick 5 minute epoxy from walmart. I can Recomend Raka 127/305 for this purpose). You will want to apply tape onto your paddle to keep epoxy from getting anywhere other than the edge of the paddle. Apply the epoxy to the edge of the paddle such that the frayed kevlar ends are saturated with epoxy. Once the epoxy has cured, sand the edge again--the formerly frayed ends will now sand cleanly off.

For sanding off the rough parts of the edge of the paddle, you will want very course grit paper (36, 50, 60) to save time. Once you have sanded it close to how you like it, you should use a medium course grit (80, 100, 150) to finish off the sanding--then you can use finer grits (200, 300, 400) to finish it off.

---

The above technique will work for a while, but eventually you will run out of "edge" and hit the foam core. To prevent this, I have heard of people making moulds off the tips of their new paddle. When you start to get jagged edges, you can place your blade in the mould and fill in the area with epoxy, acraglass or even add cloth. Obviously, this is a lot more involved.

The method for building up the edge of a paddle by either a mould or the procedure given by Pog seems great, but for most people just gradually sanding away the edge of your paddle is probably good enough. For someone who paddles daily on a rocky river, a paddle might last only last 1 year with this method, but I suspect that most surfski paddlers would easily get 5-10 years from a paddle without having to build up the tip. Obviously, the size of your paddle will slightly decrease over time.

Regarding the trimming of the edge of a paddle, I managed to easily trim the edges using a small high speed Dremel hand held drill ( 30000rpm ) .

I initially drew the cut line using a wax pencil ( used in marking tiles for cutting). The Dremel has numerous applications, one of which is cutting with small 2.5cm diameter discs ( metal cutting disc) . Following the cut I just used a small barrel sanding bit and smoothed the edges. For taking off a few mm the barrel sanding bit would be all you need. No frays, stringy bits of carbon, just a neat cut. There, now you don't have to fork out copious rands for a new paddle.

Martin