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#1 6 Mar 2015 11:44 pm

richy.s1
Member
Registered: 4 Dec 2014
Posts: 17

Cranked wooden paddle

I really wanted to make some wooden paddle but I get bad wrists so need a cranked paddle so I set about making my own. Unfortunately I cannot access the photos so I will give some instructions as best I can.

The paddle was going to be a two peice which makes the feather easy to deal with.

Shopping list:

1 sheet of plywood 4mm (no voids if possible but you do not need it all so you can pick and choose which areas you want)

a length of carbon fibre tube 30mm in diameter (the length of this depends on how long you want the paddle I bought 600mm)

Lendal Padlock spigot or similar

Some epoxy and some fibreglass

Some form of thickener like woodflour or silica

A cranked paddle to use as a template

Some old timber to make a blank which is at least 50mm thick.

Next installment I will tell you how I made it.

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#2 11 Mar 2015 1:01 pm

richy.s1
Member
Registered: 4 Dec 2014
Posts: 17

Re: Cranked wooden paddle

The first thing I did was make a blank. I use some cranked lendal nordkapp paddles so I used them as a template. The shaft is basically a straight shaft with a kink in it (It is important that it remains this way so you don't start creating a turning moment) so I just made a template of the underside of the kink and epoxied this to piece of 2" x 4". You need to make sure this is very straight. At this point both the cranks are in the same plane because the paddle is going to be a 2 peice so the feather will be introduced later on.

I cannot remember the exact diameter of the shaft but it was around 30mm so I cut 10 40mm strips from a sheet of standard exterior ply (before buying I tried to check for large voids by holding it up to the sun to see if it let light through. I had to sort through a few before I found a decent one (not sure the timber yard was too keen on this though)

When glued together this would give we a square sgaft of 2.4m x 40mm x 40mm which I would trim down after it was glued. This meant I could compensate for any slippage when I was glueing the strips.

I covered the mould in polythene sheeting so the plywood did not get glued to it then I laminated the plywood strips using cascamite glue. This process required a lot of clamps. Spring clamps were not strong enough for this so I used a number of G - clamps at the big pressure points and some quick clamps else-ewhere. I started at the middle and worked my way out. It took a lot of pressure to bend to the form but I got there in the end.

I left this to cure for a few days ( it was actually about a week but only because I was at work and did not get a chance to do any more work on it). On releasing the clamps there was not any spring back. I offered it up against my original and it was a perfect fit. I also had plenty of material to play with at both ends.

Next job was to start trimming it down to size and start rounding it off. I used a table saw and a jig saw. I initially cut it down either side to 32mm. I then marked the cranks out and cut the thickness down to 32mm. I now have a cuboid shaft. I went through the same process using the table saw and jigsaw but set the blade on a 45 degree angle. I now had an octagon.

I cut out a semicircle from a peive of old wood to use as a template and then started rounding off the shaft using a block plane and a rasp and finished with  sandpaper. This took ages and was quite tricky to keep even around the cranks. The laminations give you a good reference point to keep you on track.

Once this is done you can start thinking about the blades. I think it is best to do the blades when before cutting the shaft because the blades need to point in the right direction in relation to the crank. I will write that up in my next post.

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#3 12 Mar 2015 2:39 pm

richy.s1
Member
Registered: 4 Dec 2014
Posts: 17

Re: Cranked wooden paddle

To make the blades I used some more 3.6mm exterior ply. I made a template from the lendal blades, marked it out on the plywood and cut it out with a jigsaw. I may chop these down at a later date because I probably want a small surface area but I need to think about that some more.

I measure the scoop on the blade and marked this out onto the end of the shaft and cut it out with a jigsaw. I glued the blades onto the shaft with some thickened epoxy. I clamped this with a number of spring clamps. When this had set I ran a fillet down the joint between the shaft and the blade ready for fibre-glassing.

To ensure the blades point the right way lay the shaft on the workbench and clamp it so the cranks point upwards. When the cranks are pointing up the blades should be pointing up as well.

That is the blades complete. The next stage is installing the spigot in the middle of the shaft.

I have been searching for ages for some fibreglass sleeving so I can laminate the shaft. I have not been able to find any until now. I have found some 15mm-40mm fibreglass sleeving which I will use to slightly stiffen the shaft. I don't know whether this will work but at the moment the shaft is far to bendy. I found this on ebay from a french composites company. I spoke to a number of british suppliers and could not find any.

I am going to try and make this paddle using some laminated timber (possible ash and western red cedar) which I hope will be stiffer and will not require glassing but, again I am not sure about thisbut I will find out soon though.

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