Time for a new scratch built boat.
A couple of years ago I built 'Scullduggery' a scratch built rowing boat manned by Bionic Bill and Ben.
Scullduggery is always well received when Bill and Ben are out rowing on the lake, so I've decided to have a go at building something similar, this time a kayak.
After a bit of research, I came across a book by Nick Schade which describes in great detail how to build a full sized wooden strip kayak. There are several instructional videos by Nick on YouTube. There is also a company in Cumbria (https://www.fyneboatkits.co.uk/ ) who offer kits to build full sized kayaks based on the designs in the book. The photo of the full sized kayak is from their website.
The book includes tables of offsets for three different kayak designs. Using these offsets it is possible to draw up a set of plans. Entering all the figures from these offset tables into a spreadsheet makes it relatively easy to change the scale of the plans, but what scale to use?
The scale for Scullduggery was determined by the scale of the readily available Action man figures used for the crew i.e. 1/6th scale. Why not use the same scale for the kayak?
One concern is the load carrying capacity of the model kayak as well as it's stability on the water. The full sized kayak has a maximum loaded all up weight specification of 160kgs. This equates to only 740g for a 1/6th scale model. Not very much for the complete model including the paddler and radio gear, servos, battery, etc. Using a larger scale of 1/5th for the model improves the all up weight target to 1.28kg which may be more achievable.
At 1/5th scale, the completed model will be 39" (986mm) long with a beam of 4.8" (120mm). Using a 1/6th scale figure as the paddler should not look out of place.
As I did with the rowing boat, before starting construction of the hull, I want to be confident that I can build a mechanism that will drive the kayak, provide realistic looking paddle movement, fit inside the hull, and not weigh too much. So that is the next step.
11 days ago
Having taken a few months off from building, its time to start a new build before the weather improves and the grass needs cutting.
I currently have two yachts, a Wee Nip and Ellen, a Gaff rigged Pilot Cutter. I sail the Wee Nip most weeks, and the Pilot Cutter occasionally when the weather is suitable (it needs a 'good blow'). I decided to build something between the two in terms of size. A bit of on-line research came up with the Racing Sparrow. A design by New Zealander Bryn Heveldt. I bought a second hand copy of his book, which includes a full size plan. There is also a website where copies of the plan can be downloaded for free.
The cost of the book was less than the cost of getting the free on-line plans printed at a print shop. I have downloaded the free plan so that I can print parts of the plan on A4 sheets to use as templates. I soon found that there are differences between the plan included in the book, and the on-line plan both in terms of the hull shape, and the overall scale of the plan.
I chose this design because it is a size I hope will be easy to transport, it is plank on frame construction using balsa which I haven't tackled before, and it looks good!
The book includes step by step instructions for the complete build, including details of the materials and tools required. Good for a complete novice to boat building, although there are some strange anomalies when it comes to metric and imperial dimensions. For example 1/8th of an inch is converted to 4mm while 1/16th is converted to 1mm!
First task is to start accumulating bits and pieces, and to order the balsa.
1 year ago
34 inch Crash Tender refit
I posted a some pictures of my Crash Tender a few months ago and it was suggested that I should do a blog. So here we go.
This is my first blog, and my first boat. I am not going to provide a blow by blow account of the refit, as this would largely turn into a repeat of the excellent blogs by Rob (Robbob) and Mike (mturpin013). These two blogs have been a great inspiration and source of guidance for me over the past couple of months.
I built the boat in the early 1970s, but haven't had it on the water for nearly 45 years. Until recently, it had been collecting dust in my garage for all that time. The first task, having given it a good was to remove most of the dust, was to remove the ED Racer diesel engine, fuel tank, exhaust, etc and to fill in the exhaust hole in the transom. The diesel had always been a challenge to start, and to keep running. That, together with the unreliable, home built 27MHz radio gear is the reason the boat had been in dry dock for 45 years. A new brushless motor, water cooled ESC and 3S LiPo battery were installed in place of the diesel.
The propeller also needed replacing as the old one was too large. This identified the first problem. Times have changed since the 1970s and props now have metric threads, whereas my 1970s propshaft had a 4BA thread at both ends. A new 4mm silver steel shaft was fitted threaded M4 at each end. The new shaft diameter necessitated also replacing the plastic bushes in the shaft outer. Plastic bushes were probably not a good idea in any case. New phosphor bronze bushes were turned and fitted and it was then time to get it back on the water.
The first trial was very encouraging. The modern radio worked well, the boat was easy to start, quiet, and performed better than it ever had with the old gear. When I originally built it, I did not fit chine strakes. I cannot remember now why. It may be I didn't realise they should be fitted, or perhaps I felt they would spoil the smooth lines of the hull! Even without them it did manage to plane a little. Being fired up with enthusiasm after this first trial, I decided it was time to get back into the workshop, fit the missing strakes and start the refit proper.
4 years ago