Fitting Out a Norwegian Pram Dinghy as a Pocket Cruiser

So another week has passed and we have spent out time fitting out a variety of different dinghies, basically putting in Deck Beams, Bulkheads, and Decking in 'miniature'.

Sadly, I do not have a full set of the photographs, but have included a few to give a sense of what we achieved, as it happens we were pleased with the outcome generally speaking and certainly from a personal point of view I learned a great deal.

Probably the principle thing I learned was that you cannot build a boat by committee, well actually that isn't strictly true, you can!  However, it is somewhat slower than otherwise would be the case and with 6 individuals each pursuing their own ideas effective project management becomes an interesting exercise in damage control.

On the upside I have mastered (I use the word 'mastered' loosely) the half-dovetail beam joint; this is a joint that actually defies logic and while many drawings exist of its structure if you cut it the way it is drawn, it won't fit!  It should, it just doesn't.  It is when the beam should slide smoothly into its rebates across the beam of the boat that this realisation dawns; at this point you are told that you need to bevel off one face on one end of the deck beam... this of course then means that the joint has some large gaps...because you shouldn't have removed material from the female end of the joint before cutting the bevel that you didn't realise you needed to cut.  Got that!  The thing is you only make the mistake once.

I also had great fun spiling, scribing, and learned about the use of joggle sticks and dummy sticks, the fitting of carlins and half beams, bulkheads, and how to saw the end of the desk with a jigsaw because you didn't check the clearance before engaging the jigsaw, fortunately not my mistake...  oh the joys of power tools.

As the boats have to be used by subsequent classes and they have to be able to remove what we have put in relatively easily, we were introduced to the hot glue gun, the boatbuilding equivalent of the tack weld. Unfortunately,  we stuck a far amount in place using PU, it seemed a good idea at the time but with the wisdom of hindsight was probably a pretty anti-social gesture.  We removed the last term's efforts by the application of Olaf's size 10 steel capped work boats; I think our successors will probably need a kango hammer.

Deck beams, carlins and half beams

Coach House framing going on

Christian's addition to the cockpit... Stage 1

Decking scribed and fitted

Stage 2

Decking complete

Coamings and parsnips in place with coach roof trunking

Finished but for the coachroof...

So the end of an eventful and fun filled week, this weeks tool of choice - the hot glue gun

Next week we are working with GRP and resins building our first exam piece in the form of a model boat...

Stitch and Glue - how to build a pram dinghy

Well it has been a very busy week constructing a 'stitch and glue' pram dinghy.  Most people will be familiar with the original Mirror Dinghy, which was a stitch and glue kit built in the pre-epoxy days, but still an enormous success.

So these days we use epoxy resin and a variety of fillers, epoxy has a number of endearing features; firstly, it is prone, if left to its own devices, to burst into flames, so the secret is to mix it and apply it as fast as possible; secondly, it will stick most things with the exception of polyurethane based plastics, principle among the things it will stick are clothing to skin, and you to just about anything; and, thirdly, it sets rock hard, is impossible to sand unless you employ some heavy duty sanding equipment, it also blunts chisels and planes for a past time.

Apart from that it has revolutionised boat building...

This weeks challenge has been to master the concept of the rolling bevel, more particularly successfully creating a rolling bevel; I have not, I have however added yet another technique for making good foul-ups.  I am truly becoming the local expert on putting things right... it might be argued that they shouldn't of gone wrong to start with but where would the fun be in that.

So next week is GRP, stem assignments, and working with composites.

Flat pack boat

Several yards of garden wire and a bike spoke later

Stitched up - adding the chine

Something like a boat... at least in shape

Cramping your style 

Adding various bits

 

Moulds and Templates

Well at the end of what has been a frenetic week we now have a full set of moulds and templates for the boat!

There is also now a rig designed and we know where we are going to put the centreplate box... an important factor when considering stability.  She will now have a bowsprit and a Gaff Rig and will look very traditional albeit a considerable amount of maths has gone into designing the rig and calculating the stability curve and such things as the Centre of Effort, Centre of Lateral Resistance, and the waterline.

This past week we have also been learning about the joys of epoxy and the particularly the West System, it was a very interesting lecture from the Technical manager of West Systems which once you got past the repeated plugs for West Systems and the range of 'genuine' West System epoxy, hardener, filler, mixers, scrappers, YAWN... was very informative; it was however an unashamed 2 hour long sales pitch.

I have come across a wide range of passionate people in my time, passionate about political movements, sports, the environment, even stamps, but this was the first person I have ever come across who was capable of being passionate about glue.

The past week has also seen the introduction of Maths into the equation (pardon the pun) and dusting of the long forgotten trig. and all those formulae associated with the calculation of area and volume has led to a recurrence of the nightmares I used to suffer from at school.

Need to go and Stitch and Glue...

More later

Lofting is almost complete

Certain degree of confusion... this might be a duplicated post.

There is a reason, it is called mental exhaustion! we have almost completed the process of lofting and most of us, if not all, have certainly found it a challenge; I must confess to being perverse and admit to having greatly enjoyed the process, there is something amazingly satisfying in watching the boat unfold on the Lofting table.  However there are those who have found the experience less fulfilling, it is painful to watch grown men cry and while nobody has actually thrown themselves of the mezzanine floor it has come close.

Tomorrow we will be wrestling with Simpson's Law; this is a series of equations that allow you to calculate the waterline on any given boat by using a combination of its weight, internal volume and surface area, I think...  given experience to date, it will probably also involve casting chicken bones, chanting various unspeakable incantations, and the sacrifice of sanity and reason.

I have now prepared the first shopping list to construct the stem, apron, keel, hog, stern knee, deadwoods, and transom.  This is the backbone of the boat which has to be put in place with the moulds to allow planking to start, its a lot of Oak!  Sadly it will almost certainly be French Oak, Nelson must be spinning in his grave.

I think you have probably seen enough photographs of Lofting so I will wait until something more interesting occurs....