Day 3

Today has seen real progress, we have put the Apron through the thicknesser, laminated the Stem and the Stern knee and scarphed the keel.

Day 2

Laminated the Apron and keel sections.  Planed up and fixed the transom planks ready for the transom to be cut out tomorrow.

We are currently on schedule on Day 2.

Stem Assignment

So...

Stem Assignment: what is it?

The purpose was to construct a stem for a 10' dinghy using laminated ash.  The first stage was to produce a lofting from a table of off-sets and then design construct and use a laminating rig.  There are two ways you can undertake this task, the easy way, and the 'Why not make it as difficult as possible.' way; you guessed.

It was all going so well and I was right on the curve, in fact ahead of it... Pride before a fall.  At 3 in the afternoon I realised, or rather it was pointed out that my buttocks didn't line up with my half breadth waterlines, this is not a good thing.  It was definitely a *$**@^ moment, however, having realised that the lofting I had so lovingly constructed was gash I had to redo it and that was the first late night.

Lofting with revolved sections

So I then constructed the Laminating Jig which actually went really well, now at this point it is important to note that I had gone for the 'Two part' construction method to allow for easy construction of the rabbet (the rabbet is the rebate into which the planks fit.)

Jig set-up

OK so far so good and we are back on track and moving forward rapidly.  Next comes the gluing up and clamping the laminate onto the jig, this is a 3 man job and not for the faint hearted, once again this involves glue... need I say more, however, we did get it glued up and onto the mould with the parting strip in place.  Had I mentioned the parting strip. Ah!  This is a laminate that is covered with parcel tape to ensure that when the clamps are undone the laminate is in two pieces that fit exactly together, an inner and an outer stem.

So... what could possibly go wrong, you can turn the laminate stack over by accident with the result that the Inner stem ends up on the outside, which is not good, in fact it is catastrophic, hence the following series of photographs which show me gluing the whole thing back together and having to use the traditional method of chiselling out the rabbet, long painful and definitely not part of my skill set.

So thats it glued back together...

It then only remains to cut it out using a chisel, which let me assure you is a long and painful process.  The process is still ongoing and should be completed in the next few days, building the Jessica Rose allowing.

JESSICA ROSE - Daily update

Well the build has started!  I will therefore post a short 'Daily Report' on progress.

Monday 26th June 2011.

Constructed keelway and secured in place. Cut 56x2000mmx60mmx4mm Oak laminates. Constructed laminating jig for the Stem and Apron.

Purchased a Router, Angle Grinder, and Random Orbital Sander, Veritas measuring gauge, Long steel tape, second hand number 4 Plane, and a high quality steel rule.

SO... Where was I ?

OK, This picture of a Carvel section should have appeared at the bottom of the page but has arrived here
I do not have a clue how to move it:  So please hold this image in your mind and insert it at the appropriate point in the text.

Ah yes, the joys of Geralds and scarphs, spilling and fids...

This is a man spilling (Pronounced spyling)

As I previously mentioned we have also done some cold moulding, a process originating during the Second World War when it was called 'hot moulding' and was used primarily for producing the fuselage of the Mosquito.  It was called hot moulding because the glues used needed to be baked at high temperature.  It's now called cold moulding because, yes you guessed, modern glues don't need to be heated in order to cure.

Now I am utterly confused, I cannot appear to get below the picture of Cold moulding so hold this image in your mind because I am about to throw in some pictures of carvel and clinker...  This is where you need to insert the picture of the Carvel Section that appeared at the top of the page; confused so am I. 

 Next time I will try and get the photographs in the right place.   Ok I am in danger of becoming a huddled, burbling heap it at this point so I shall give up while I am ahead.  I promise I will deal with clinker, just when you thought you had escaped! and I will recount to you the tale of the Laminated Stem or, as I know it How to make things really difficulty for yourself.  Adios Amigos.

Cold moulding in progress

Planking - of various kinds...

OK...

Plastic is behind me for the moment and once again I am breathing styrene free air;  we have spent the last week involved in learning the intricacies of various types of planking, namely, cold moulding, carvel, and clinker.

Man contemplating 'Gerald'. Which is not the name of the boat!

We have also learnt how to create a 'gerald' and also an 'Admiralty gerald'.  You are all absolutely riveted I can tell, well I am sorry there is no escape:  A gerald is where the planks taper into the rabbet at the stem of a clinker built boat, a 'gerald' (non-Admiralty) is in fact a rolling bevel that starts about 9 inches back from the hood end, this allows the next plank to fit snuggly into the rabbet. So there you have it.  The truth is it is a nightmare to get right and I look at stems on clinker boats with new found respect (for their creator) and deep suspicion; having completed a couple I now know what might be lurking behind the plank.

Clinker construction also involves a process called spilling, this allows you to create a template of the next strake that you are creating, all strakes (planks) are not created equal and vary along the length of the boat normally tapering at each end.  However, for the boat to look 'fair' the strakes need to have an even run to them, otherwise you end up with a boat that can just look plain ugly.  Yes, this is more about art really and having a good eye for what are fair curves...  must go need to laminate, more on this fascinating topic later!

A few photographs

A Chip of the Old Block

Application with a band saw and planes of various kinds produces a  'Plug" or male mould.

The first of several layers of gelcoat and Glass designed to create a 'female mould'

Et Voila! (or something like that)

Following the laying-up of a hull shape in the mould, and considerable effort in getting it out we have a small model boat.  This one floated and is quite stable!

Preparing the deck mould for a slightly larger model.

The gelcoat laid up on the mould

A selection of preprepared resin batches without the catalyst!

40 minutes frantic activity and the vacuum bag is in place, sealed and running.

The same process produces a hull....

These are photographs of working with Glass fibre....

If God had meant boats to be made of plastic...

 ... He would have created plastic trees!  Not original I am afraid, it came from a teeshirt in Cowes.

The past week was spent working on various forms of 'plastic lay-ups' and 'vacuum bagging', (which, I hasten to add, is not some form of Public School initiation or perversion), culminating in our first assessed assignment, constructing a model of a racing yacht approximately 950mm in length.

Basically, if you start from the premise that everything in building a Fibre Glass hull is toxic and dangerous to the environment and potentially to one personally, you can't go far wrong.  That said it is a useful addition to the Boat Builders range of techniques and in the current environment is essential given the very high proportion of GRP and Epoxy boats that are on the market. (I should stress that once cured it is perfectly safe - well unless you start drilling it or sanding it.)

As a manufacturing process however, while I am sure there must be economies of scale, it appears to be massively wasteful in nitrile gloves, brushes, mixing pots, mixers and cured resin, all of which appears to have a half life of about 10,000 years in land fill:  This is not an environmentally friendly process.

The matrix (the term for the liquid bit of the laminate before it has cured) is made up of polymer resin and an initiator (Methyl Ethyl Ketone Peroxide - YES it is as nasty as it sounds) the resin uncured remains viscous and extremely sticky and is impervious to just about everything, when the initiator is mixed with it it initiates an exothermic reaction during which it hardens... there is a certain imperative to get it where it is meant to go.

Sadly, this isn't always as simple as it appears and you tend to end up with your clothes stuck to your skin and pencils and miscellaneous tools stuck to the bench, floor, or yourself.  In the midst of this you are trying to place and 'wet out' the reinforcement (the Glass fibre) which in turn sticks to the brush, tools, bench, etc, etc.

Add to this the concept of pigmented Gel Coat, noting that the pigments like the Resin don't dry unless they are part of the cured matrix, and you are in a whole world of pain.  The pigment gets everywhere, is sticky, and can only be removed from one's hands by abrading off the top couple of layers of skin.  The Gel Coat is also the shiny bit on the outside, which you can't see until you turn it out ofd the mould, at which point you find that the brush you used had decided to moult.

The other thing to bear in mind is that when working with 5 other people in a space the size of a longitudinal double garage it doesn't really matter how clean or careful you are, somebody else will ensure that there is enough pigment, resin, etc. around so everybody can share that unique sticky experience.

Photographs will follow in the next post once I have completed filling the gaps and polishing up my model boat...

Still hard at it...

I apologise for the delay in posting the latest from the BBA but unfortunately I had forgotten my password! Normal Service will now be resumed...