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Author Topic: Nottingham J class build  (Read 1885 times)

SailorGreg

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Nottingham J class build
« on: August 31, 2017, 05:45:25 PM »

My first love has always been sail, model and full scale, and for some time I have been lusting after one of Alan Horne's J class hulls.  Finally I have bitten the bullet and am now the proud possessor of the hull and the laser cut parts to complete it.  This is the full hull Nottingham version rather than the original Canterbury one.  (If you are confused by this, you can do no better than to visit Alan's website here.)

Alan provides the hull and the ready moulded lead ballast to fit, as well as the wood parts to build the internal structure and deck (as well as a stand).  Everything else you provide yourself, so I guess you need to understand a little about how a model sailing boat works.  Although I have a Victoria and a Dragon Force 65, my knowledge of larger models is a bit sketchy on some of the details, so I will be learning as I go along!  O0

The pictures below show the hull as collected from Alan.  It is a lovely moulding, smooth and unblemished, and I dread the first scratch!  I am following the instructions provided by Alan (read them on his website) pretty closely, although I will point out if I diverge from them (and why).  The first step is to float the hull with the ballast loosely in place and confirm that it is level in the water.  The pictures confirm that it is spot on, which is a credit to the builder.  I had to fill the bath pretty full to get the keel off the bottom!

Next step is to fit the rudder, which requires drilling holes in that pristine hull.   :o   See how I got on in the next exciting episode!

Greg

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Re: Nottingham J class build
« Reply #1 on: September 02, 2017, 01:50:26 PM »

 Fitting the rudder requires making holes, ideally in the correct place.  I followed the instructions to situate the hole in the hull, taping a 10mm drill down the back of the keel and marking where the tip touched the hull (pic 1).  A deep breath and a hole is drilled, then gradually enlarged to take the rudder tube. The tube itself needs a fairly acute angled cut to match the hull, and I used a tapered dowel to hold it firm while the cut was made (pic 2).  The hole was then teased out until the tube was a good fit – and yes, I did chip the gel coat (pic 3).   >:-o   Something to fix towards the end.


The heel fitting which holds the rudder at the bottom of the keel was reasonably straightforward to fit, and I did take note of the instruction to countersink the fixing screw to make sure the ballast seated properly at the bottom of the keel moulding.  I did need to improvise an extended allen key to do this screw up, as space down there is pretty tight. Then check that everything fits and the rudder moves easily (pic 4).


At this point I stole an idea from some American J class builds, and put a small ply dam just in front of the rudder tube (pic 5).  This is to allow a pool of epoxy to surround the tube, which almost guarantees a waterproof join and provides good solid support for the tube (pic 6).  I taped up the bottom of the hull to stop the epoxy dribbling through, although a little did squeeze by and I found I had a small plug of epoxy in the tube when it was set.  Easily fixed with a drill or two.


I was now finished with the rudder and moving to work on the inside of the hull, so I took some steps to make sure I didn’t damage that lovely hull finish.  First, I put a coat of wax over the outside, then ran some masking tape along the top of the hull (pic 7). I then taped some plastic sheeting over the hull to keep out all those drops of glue, sharp tools and sticky fingers that would mar the shininess (pic 8).  Time will tell if it works!


Next will be fixing the ballast and building the internal structure.  Everything seems to be going OK at the moment.  :-)) I wonder when it will go wrong!  ;) Fingers crossed!


Greg

 

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Re: Nottingham J class build
« Reply #2 on: September 08, 2017, 06:03:10 PM »

 The next step is to fix the ballast in place.  The instructions spend some time emphasising the need to remove the odd bump and lump in the layup to allow the lead to sit as low as possible in the hull, so I spent some time with the Dremel flexi-drive grinding out spots where the lead appeared to catch (leaving a useful grey mark on the hull).  (An essential tip – don’t drop the lead into the hull without a piece of string on the bolts to lift it out.  %% )  After a while I felt I had just about exhausted this process, although the lead wasn’t appreciably lower in the hull than it had been when I started.  I suspect the inside of the hull was a pretty fair moulding to start with.  :-))


At this point I followed Alan Thorne’s advice to remove a section of the ballast to improve the sit of the boat in the water.  I suspect this would be frowned upon by those who race, but I have kept the removed part against the day it needs to be replaced.  Then it was out with the epoxy and a gentle pour to fill the gaps around the lead.  I had to stop when the epoxy reached the level of the cut out section or it would simply have filled that space.  (Pic 1) When the first pour had cured, I sealed the gaps between the cutout section and the hull with blu-tack and poured a little more around the rest of the ballast to seal up to the top of the lead.  I did want to make sure that any water that might find its way into the hull could not hide away between the lead and the hull moulding.


Once the lead was firmly in place, it was time for the internal wooden parts.  The strips provided for the inwhales which support the deck around the hull edge were shorter than the hull so two needed joining together, which I did with a scarph joint.  I find this easiest with these small sections if the two pieces are tacked together with a couple of drops of superglue, the scarph is marked and cut on both pieces at the same time, then the pieces are popped apart, one is reversed and the two glued together.  I hope the pictures (2-5) show this well enough.


The bow and stern fillers came next. These need some sanding to fit, but I was a little too keen in some areas so the parts tended to slip down below the level of the hull.   :o   I fixed a piece of scrap to both parts with double sided tape to hold them level with the hull for gluing (pics 6, 7), then fitted the inwhales (pic 8 ).  These were glued in with epoxy thickened with colloidal silica, and the help of a stiff batten around the outside of the hull – the hull is still very flexible around the top and lots of point clamps runs the risk of inducing a ripple in the hull (pic 9).  Now I could dry fit the rest of the beams (pic 10).  Starting to look the business!


Happy modelling!

Greg

 

SailorGreg

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Re: Nottingham J class build
« Reply #3 on: September 08, 2017, 06:12:18 PM »

 A couple of small points.  First, I drilled a shallow 1mm hole bang on the centreline right up in the bow (not too deep – you don’t want to pop out of the hull!  {:-{ ), pushed a small panel pin into the hole and looped a piece of thin twine over it (pic 1).  With a weight hanging over the stern from the twine, this acted as my centre reference for all the subsequent fitting, but could be easily moved aside for trying the fit of parts.  I also found that the mast deck (the part with the D cutouts in the last picture above) needed some support between the beams so added some scrap to stop it falling into the bottom of the boat (pic 2).  The instructions suggest this should be glued and screwed to the beams, but I have dispensed with the screws.  I have considerable faith in modern glues and am happy that gluing alone will be more than strong enough to hold everything together.  I hope!


Greg

 

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Re: Nottingham J class build
« Reply #4 on: September 08, 2017, 09:20:11 PM »


Looking good Greg!   O0
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SailorGreg

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Re: Nottingham J class build
« Reply #5 on: September 08, 2017, 10:26:15 PM »

Thanks Martin - although the photos make it look like I do my gluing with both eyes closed!   :embarrassed:

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Re: Nottingham J class build
« Reply #6 on: September 12, 2017, 04:54:20 PM »

 Having got most of the structure dry fitted, I then started the gluing.  For this I mostly used Gorilla glue, which seems to glue almost anything to almost anything else pretty effectively.  You do need to clamp pieces in position as the glue foams and expands, and might push a piece out of place if not held firmly.  Pic 1 is the mast deck glued in.  The instructions suggest cutting the hole for the mast tube before fitting, but I felt I was more likely to get the hole exactly central if I cut it in situ.  Pic 2 is this in progress, using a burr in a Dremel flexi drive to open the hole out, and pic 3 is the finished hole.


Pic 4 is the mast tube and the marked out lower support, which sits down in the hull and locates and braces the mast tube.  I made a mess of cutting this hole and had to add a piece to cut a new hole as you can see from the dry fitting of the tube, pic 5.  The mast tube normally comes with the kit, but Alan Horne was out of stock and pointed me to PJ Sails for this part (and I also ordered most of the hardware I think I will need from here, not to mention a suit of sails). I commend Peter Wiles for great service – I spoke to him before I placed my order and mentioned I really needed the tube now, so he took my address and posted it to me before even receiving my formal order, let alone any payment. Thanks Peter!


I didn’t complete the installation of the structure at this point as I still had to make and fit the sail winch assembly, so that was the next step.  I did some experimenting and found my sail winch (a Hi Tec HS-785HB) makes 4 full turns on the full throw of the transmitter stick.  That amounted to about 50cm of travel, which was rather more than I believed I needed. As my transmitter (Planet T5) has no end point adjustment, I initially thought I would need some sort of physical stop on the transmitter.  However, I reckon I am going to need about 25cm travel so the simple thing to do is use a 2:1 on the winch line.  This would have several effects –
1.       I get the correct range of movement – good
2.       The strain on the winch is halved – good
3.       The time to sheet in or out is doubled – bad
So two good things and one bad.  As I am not going to race the boat (at least not seriously), the sheeting speed isn’t critical, and I hope for more of a stately progress around the lake as opposed to a frantic flurry at a mark.  So I went with the 2:1, with an elastic to keep the tension on the winch line.


The suggested sheeting system uses a slider on a rod or track.  Alan Horne recommended Silent Gliss curtain track, but I looked at the price (over £20 for a 1 metre length) and decided I would use what I had to hand.  This turned out to be some 8mm carbon tube and a sheet of PTFE.  I made up a PTFE slider using the brass screws provided for the wooden parts, and although I might have done a neater job, it slid very nicely along the carbon tube (pic 6).  I then lashed together a trial setup to make sure I hadn’t made a complete faux pas somewhere (pic 7), and everything seemed to work fine.  The elastic in the picture is a little fierce, but was all I had to hand.  I will substitute something a little gentler in the final setup.  A close up of the jury rigged slider is in pic 8.  This whole assembly is removable from the hull, so if it turns out to be less than effective, I can modify or replace it fairly easily.  :-))


Once I had convinced myself I could make this all work, I was ready to install the fixed part of the sheeting system in the hull and complete gluing in the wood structure. However, before that I acted on a suggestion from Alan Horne, namely to fit something to the ballast to provide a lifting point that didn’t rely on the deck and hatch structure.  I had some stainless M4 studding, so that seemed to fit the bill.  I drilled a hole in the aluminium strap that holds the trim weight in place and fitted the studding, pic 9, in what I judged to be the balance point of the hull.  Then the remainder of the wooden parts were glued in, assisted by various clamps and elastic bands, pic 10.  In this picture you can also see the base for the sheeting system in place, along with the removable section which carries the winch and moving parts.  You can also just see on the right clamps keeping the hull beam within tolerances as the glue dries.  The top of the hull is still quite flexible and can easily be pushed out of shape, something to watch when gluing these pieces in.


Coming along nicely! A few more details internally then on goes the deck.  :}


Greg

 

SailorGreg

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Re: Nottingham J class build
« Reply #7 on: September 16, 2017, 05:52:19 PM »

 Well, the “few more details” I mentioned last time seem to have taken a little while  %) .  Firstly, I found that the two longitudinal pieces that form the edges of the main hatch were curved.  Not sure why, the sheet of ply they came from seemed flat enough, but there it is.  They were both curved the same way, so the hole for the hatch was offset by up to 2-3mm (pic 1).  At first, I thought I would just put a couple of small beams in at the midpoint to push/pull the pieces into line.  But the hull isn’t completely rigid, and when I tried it the hull edge moved as much as the curved piece. Hmmmm!



After some head scratching, I took a piece of 1.5mm ply and cut it to fit as shown in pic 2.  The straight edge of the ply keeps the port piece straight and is braced where there is a lot more rigidity in the hull.  The half beam that will form the front of the hatch opening then pushes the starboard piece straight as well, so problem solved!  I did wonder if I needed a piece on the other side just to balance the boat, but decided the weight of this was not going to make a lot of difference.


Around about now I tried lifting the hull with the piece of studding I had installed and noticed that the aluminium strap the studding is bolted through flexed slightly.  I worried that this movement would be transferred to the deck when I lift the finished boat, so I decided to put a self-tapping screw through the strap and into the ballast next to the studding.  In principle this is straightforward – drill a hole, put in screw.  But I needed to drill a hole down in the bottom of the hull between the various pieces of wood I had just installed. I couldn’t get any power tool down there so had to resort to a hand drill (pic 3).  Anyone who has tried drilling lead will know that it is a real pig  >:-o . It took me forever to drill the hole, but I persevered – pic 4 shows the screw in place.  And there was no discernible movement of the strap when I lifted the hull.  Hooray!  :}  I also added a small piece of ply to stop the studding waving about too much (pic 5), although I am not sure how necessary that will be in the end.


In the build manual, Alan Horne places great emphasis on making sure the inwhales and other structural pieces are at or just below the level of the hull edge to allow the deck to sit flat and true.  I was not as careful about this as I should have been, and when I checked with a straight edge across the hull, there was a bit of a problem in a few places, especially around the mast deck area.  Here the straight edge was 1-2mm above the hull edge.  <:( The inwhales are fairly soft wood, so will sand down to the correct level easily enough, but the ply pieces are made of sterner stuff.  I resorted to my random orbit sander with some 120 grit paper.  To make sure I didn’t take the hull edges off as well, I started by running a permanent marker along the edge of the GRP shell.  As soon as this began to disappear, I stopped sanding in that area.  A long, dusty period later I was back where I should have been all along.  Pic 6 shows this process with a little of the black marker still visible in the bottom of the picture.  I finished the sanding off with a rather more gentle progression along the hull with a piece of wood with some finer grade paper glued to it, pic 7.  If you are building one of these lovely models, PAY ATTENTION TO THE INSTRUCTIONS!  I will in future.  O0


I then tried the deck on the hull (pic8).  I am very happy to report that the laser cut holes for the hatches lined up exactly with the beams, and everything looked like it fitted pretty well around the hull.  But still a couple of things to do before gluing it down.  Next time.


Happy modelling!


Greg
 

SailorGreg

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Re: Nottingham J class build
« Reply #8 on: September 25, 2017, 01:31:13 PM »

 A few more “little details” – like installing the mast tube.  This is an oval tube that allows the mast to rake fore and aft while still providing robust support to the rig.  The tube needs a little work before fixing, not least the shaping of the bottom to fit the hull and plugging to make sure any dribbles that get into the tube don’t carry on into the hull.  Pic 1 shows the odd shape needed at the bottom of the tube and the epoxy putty I used to seal the bottom.  There also needs to be a positive point for the mast to step onto.  I put a 3mm stainless steel pin through the tube which will engage with a slot in the foot of the mast, supporting it and preventing any rotation.  Pic 2 shows the hole for this and the source of the pin – dinghy sailors will recognise the frame of a burgee (wind vane), the staff of which is 3mm stainless.  :-))


Then it’s back to the test tank to make sure the tube is set vertically in the hull.  Fore and aft is not particularly critical, as the adjustable rake can make up for small variations.  But athwartships the tube HAS to be vertical in the hull to ensure the mast stands true to the waterline when viewed from the bow or stern.  I put the spirit level back on the hull to check it was still floating level (it was) and because I didn’t have my mast tube at this point I took a piece of carbon fibre tube, wound on some masking tape to make it a snug fit in the tube then hung a line from the top, offset to one side.  The tube needed a fair bit of work on the bottom shaping to get it spot on, but pic 3 shows that it ended up pretty good.  Once I had everything square, out came the epoxy and the tube was glued in place.  I slid the tube through the mast deck, slid on the intermediate mast support (which isn’t glued in place at this stage), slid the support pin through its hole and tacked it in place with a quick dab of superglue, pic 4. I then put a large dollop of thickened epoxy in the bottom of the hull where the tube would sit and slid the tube down into its final location, checking that it was still vertical. I left the boat sitting in the bath until the epoxy had set, worried that if I tried to lift it out I would jog something out of line.  I also put a dab of epoxy around the ends of the support pin to seal that in place.  Once this was all set, I did a final check - all square!  :-)) :-))   Then the intermediate support was glued to the hull.  The whole structure now feels rock solid with the tube fixed at deck level, at the keel and half way between.



About now my hardware order from PJ Sails turned up so I fitted the backstay fixing.  I dry fitted the deck, which is now located with the mast tube and the lifting studding, so cannot rotate.  I checked the deck overhang and it was pretty even all round the hull, which was good as it showed I still had pretty good symmetry.  I then drilled a hole for the eyebolt near the stern, pic 5, and in an ideal world that would come out smack on the centreline of the underlying piece, pic 6.  OK, not spot on, but I think it’s more important that the fitting sits central to the deck marking, and I am happy with this.  I then drilled and tapped a small piece of aluminium bar to take the M3 eyebolt, and glued this under the stern piece, pic 7.


Once the deck is glued on, there is precious little scope for working on the internal parts of the hull.  I spent a fair while looking for places where I might need some reinforcement to take the rigging and sailing loads.  Because I had sanded the inwhales quite thin, I felt some beefing up was going to be needed where the shroud fixings screw to the deck.  I added two pieces of ply under the mast deck to take these screws.  Pic 8 shows these sitting in place on top because it’s easier to photograph them here than when they are glued underneath! (and yes, the mast tube is still overlong, I intend to cut that down to size just before fitting the deck).


I also checked the fit of the mast rake adjuster, pic 9.  It seemed to me that the screws for this could just miss the edge of the plywood so I added a couple of small pads to make sure there was some meat for these screws, pic 10.


With all the hardware to hand, the next job will be to finalise the sail winch and sheeting arrangement, again before the deck goes on in case there is some more work needed up near the bow.  Can’t be too careful!



Happy modelling!


Greg

 

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Re: Nottingham J class build
« Reply #9 on: October 01, 2017, 10:06:48 PM »

Great build! Thx for all the pics and info.
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SailorGreg

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Re: Nottingham J class build
« Reply #10 on: October 04, 2017, 05:25:31 PM »

Thanks xrad – it’s nice to know someone’s watching!

Some might think I am getting paranoid about beefing things up before the deck goes on, so here are a few more reasons to confirm that view!  Firstly, the mainsheet lead on the deck will sit between the two hatches and the mainsheet then runs through a bridle which spans the main hatch.  There is no structure between the hatches other than the 1.5mm ply deck, so I filled in the space with a piece of ply to give the fitting something to grip.  Pic 1 shows the lead in place including a piece of carbon tube to lift the exit point above the hatch.  The fitting next to it is an identical one (for the jib sheet) so you can see what there is under the deck.  I also added some pieces where the bridle fixings will go as shown in pic 2.  I then moved forward to the jib sheet lead.  As I was drilling a 5mm hole in the 10mm king plank, I added some material each side of the king plank and put the fitting in place to test the lead to the winch.  I found that even moderate sideways pressure on the sheet caused the king plank to twist.  I guess that when the deck is in place everything will stiffen up, but I was taking no chances so added some braces to the hull, pic 3.  My final job before adding the deck was to fit a block to lead the mainsheet forward to its turning block on the sheet winch structure, pic 4.  Having added all these bits and pieces, I thought it worthwhile to make a note of where they all were as I might not remember when the deck was on and hiding them from view! So I measured and noted down where the added pieces were, pic 5.


One refinement suggested by Alan Horne is to stain the margin planks and king plank on the deck.  I did this with a dilute mix of burnt sienna watercolour paint, and the result can be seen in pic 6.  Finding no more excuses to delay, the deck was then glued in place.  I prepared a large number of masking tape strips to hold it down (pic 7), and also in that picture is the roller I used to spread epoxy resin over the underside of the deck.  I also brushed epoxy onto the mating surfaces of the hull structure, then thickened the remaining epoxy with colloidal silica and ran a bead of that along the edge of the hull and round the hatches. On went the deck, on went the tape and clamps, and it was too late to change my mind, pic 8.  Time to go away and let things set.


Some while later, off came all the tape and the clamps and the deck looked fine, albeit with some epoxy ooze around the edge.  This wasn’t too much of a problem as the masking tape placed along the hull top prevented this from sticking directly to the hull.  After I had sanded the deck overhang very nearly flush with the hull, some gentle encouragement lifted these pieces away without too much drama. 



With the deck in place, I cut the mast tube down to size.  The instructions suggest leaving this a few mm proud of the deck, which sounds a good idea to stop every stray trickle of water ending up at the bottom of the mast tube.  I cut the tube off with a cut-off disc in the Dremel but made sure the tube was blocked up and the deck protected from the metal dust (pic 9).  I wasn’t too keen on the bare aluminium showing, so I made a wood collar to sit over it, pic 10.


Now a small diversion – during my fairly long period of yearning for one of these models, I have read several accounts of other builds (such as this) where the builder has planked the deck.  I had always hankered after this for my model, but initially thought that might be a step too far.  However, having got to this stage I find that, while the supplied deck is fine and will no doubt look splendid on the finished model, I know I will not be satisfied unless I put a proper planked deck on the hull.  The deck I have just fixed will be an excellent sub-deck to take the planks, so no effort has been wasted (apart perhaps from the staining, but that was very little time).  The wood for the deck is on order, so the next thrilling instalment should be some deck planking – watch this space!


Happy modelling.


Greg

 

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Re: Nottingham J class build
« Reply #11 on: October 04, 2017, 08:55:13 PM »

Hi Sailorgreg, How wide are you going to have the deck planks?  If you are going for an actual J class yacht, will you get in the extensive deck detail they had with many winches etc?
I have built and sailed the Amati larger Endeavour, comes out a little smaller at 1 metre long, planks were 2 mm wide at this scale, I think 76 planks wide at one point.  On the Endeavour the quadrilateral jib really shows it off when sailing.
It all looks very nice, it is good to have a record of the build.
kind regards Roy

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SailorGreg

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Re: Nottingham J class build
« Reply #12 on: October 05, 2017, 02:30:52 PM »

Hi Roy, I am not going for the full scale job.  No winches or deck houses, just some "representative" hatches over the holes in the deck.  The wood for the deck arrived today (well, yesterday actually but I had to collect from the Post Office today!  >:-o ).  It is 5mm wide, 1mm thick lime from Cornwall Model Boats - super service and good quality stuff.  Not sure yet if I am going for black caulking or leave that out and just have a plain deck.  I think I'll knock up a trial section with caulking and see a) how easy it is to get it neat and b) whether it looks the part.  I do plan to have the planking follow the curve of the hull rather than straight fore and aft.  The strips are flexible enough that they should take up the curve fairly easily.

Watch this space!

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Re: Nottingham J class build
« Reply #13 on: October 05, 2017, 04:55:57 PM »

Hi Greg, I think at that scale the cauliking hardly shows up.  I found that using white glue the glue softens the wood and it follows curves quite easily.  Have you seen the Nauticalia video sailing in the thirties?  It starts with the construction of the J class Endeavour and as you have realised all private yachts had planking following the curve of the hull, you will also see that the planking was reduced in width gradually as you reach the ends of the yacht so all the deck planks were tapered.
 I would not bother, if I see your model I won't say a thing and keep the secret safe.

Also I don't think that the J class had aerofoil section masts but were circular in section and tapered as they went up, (sails were connected with mast hoops).  They were constructed from shaped lengths of wood and were hollow inside, I expect some were metal anyway.
Contrary to what people think (not you and I of course) all the racing J class were metal hulls and around 130 tons displacement.
The only wood hull was constructed recently using epoxy and strips of wood.  The racing hull had virtually nothing inside her as she was just meant for a few hours racing at a time. 
The refit that many of the surviving boats have had has increased their displacement and Endeavour is a foot lower in the water, fitted with an engine and propellor, something to do with Health  and safety, so there you go!

If I may suggest a point and that is pay good attention to the sails, they must not look baggy, Use a modern terylene or stiffish cloth.  I used drafting film and a feature of the Endeavour was the triangular boom, wide enough for 2 men to walk down side by side.  The wide flat top to the boom was used to adjust the sail to an aerofoil curve, my one has a reduced number of sewn on sail positioning points but no one noticed when the artcle was published.
Another point is do not use a brush to paint the deck.  When it is laid use a razor blade to scrape down the surface (no sand paper) when satisfied use a cloth wrapped around a finger to rub the varnish on in thin layers.  This way the deck looks flat.

Have you considered how the boat will travel and possible erecting of the mast and sails at lakeside?  Especially if it is windy.

kind regards Roy


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Re: Nottingham J class build
« Reply #14 on: October 05, 2017, 05:03:11 PM »

Surely the Nottingham J
is a much different kettle
of fish.
Ned
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roycv

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Re: Nottingham J class build
« Reply #15 on: October 05, 2017, 05:14:22 PM »

Hi netleyned, There is a certain air about a large yacht with some deck detail, it is not a class racing boat which seem to have gone to extremes these days. 
The other end of the scale is a pond yacht, I have one about 3' 6" and this falls more into the toy boat category, couple of hatches and the sail control and polished brass fittings tell their own story.

On the J class there is a lot of deck though and leaving it bare when the deck has been neatly planked is a shame.
Hence my thoughts as above.
best regards Roy
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SailorGreg

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Re: Nottingham J class build
« Reply #16 on: October 06, 2017, 02:15:37 PM »

Yes, there is no doubt that the Js were at the leading edge of technical innovation, just as the America's Cup boats are today.  I stand in admiration of the wonderful scale models produced by some, but mine will be "stand-off" scale at best.  What I really want is an elegant model yacht, not a faithful reproduction of a particular J class.  But I still want a planked deck, scale or not!  As for sails, these are on order from Frank Parsons at Nylet and will, I am sure, exhibit not a vestige of bagginess!  (Astute readers might recall I said that the sails were coming from Peter Wiles, PJ Sails.  Fortunately for him but unfortunately for me, he is really busy and his delivery was well into next year.  Having had sails from Nylet before and been very happy with them, I had no qualms at all about placing my order there.)  As for the mast, that is a tube, not aerofoil (as required by the Canterbury J class rules) and the oval mast tube in the hull is that shape to allow some movement for raking the mast fore and aft.

I certainly have considered transport.  The rig will live separate from the hull until I reach the water's edge, when the boat will be rigged. The whole ensemble will be over two metres keel to mast head so transport fully rigged is out of the question unless I go and buy a large van (which I am not going to do!). 

I am still carefully sanding the deck edge flush with the hull at the moment, trying not to scratch that gleaming gel coat.  There are one or two places where I have failed and some polishing will be required once I have finished with all the building, but no major dramas I'm happy to say.

Happy modelling folks!

Greg

WeymouthJohn

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Re: Nottingham J class build
« Reply #17 on: October 06, 2017, 05:33:43 PM »

This is a really useful thread since although I aspire to a Nottingham J, I'm cutting my teeth on a Moonbeam and there are a lot of good tips here for me ..... so thank you.
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John

Daleb

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Re: Nottingham J class build
« Reply #18 on: October 06, 2017, 07:24:06 PM »

Looks great Greg  :-))
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SailorGreg

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Re: Nottingham J class build
« Reply #19 on: October 16, 2017, 10:57:32 AM »

Thanks Dale.  I hope you will be able to say that when it's finished!  :}

 I finished the careful sanding of the deck edge flush with the hull.  I found it easier to do this if I tilted the hull so I put a couple of clamps on the stand to make the deck edge easier to see (pic 1).  Then I added some coamings around the hatchways.  The material provided with the hull includes some aluminium angle that can be bent or cut to provide the upstand here, but I like cutting up wood so I used some 1.5mm birch ply, pic 2.  Then it was on to the deck planking.  I started with some mahogany to make the bow and stern pieces.  The bow piece was relatively straightforward, pic 3.  The stern piece had a couple of “wings” glued on to prevent too much cross-grain in the finished piece, pic 4.  The stern piece was then shaped to a pleasing curve (well, it pleased me!  :D ), pic 5.  I did one half freehand then made a template from that to get the other side the same(ish).  These parts were then glued on the carefully measured centre line – you can see from the pics that the original deck hadn’t ended up as symmetrical as it should, part of the reason for my decision to go with planking.  I then put a mahogany king plank down the centre of the deck, again making sure it was smack in the middle.  O0


The next step caused me some head scratching.  I had bought some 5mm wide mahogany to do the margin planks along the deck edge.  I needed to glue these exactly flush with the edge of the hull but there was nowhere convenient for clamps or pegs and I didn’t think masking tape was going to hold the precise curve needed.  In the end, I made a gauge with a small piece of the mahogany strip and a piece of scrap glued on its edge, pic 6.  I then cut up lots of little ply triangles and used the gauge to spot glue these along the inside edge of where the margin plank will be.  I hope pic 6 shows this clearly, and pic 7 shows the series of little stops in place.  I then ran a bead of CA along the deck edge and starting at the bow I pushed the strip against the stops.  The glue grabbed quite quickly and I just worked my way aft, pushing the strip into position.  Worked like a dream!  :-))   Pic 8 shows the finished job, and most of the little stops just popped off with the help of a sharp chisel.  One or two were firmly glued but were easily shaved away.


I had played around with some black paper as caulking for the deck planks but wasn’t very keen on the finished effect.  Also, when you view a full size boat from a distance that allows the whole hull in the field of view (pretty well how models are viewed all the time), you can’t really distinguish individual planks and the caulking between them. So I decided to plank without any caulking, and pic 9 is the first plank in place.  Again, just a bead of CA along the line of the plank and a steady pushing into place with some masking tape to help hold it there.  So far, so good.  :-))


Happy modelling!
Greg

 

xrad

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Re: Nottingham J class build
« Reply #20 on: October 17, 2017, 01:00:22 PM »

Too late now, but the easiest way to add caulk is by black(or white or whatever) coloring of elemer's glue (w/water based paint) and spreading it between finely spaced planks....then sanding down and coating w/polyurethane. Better done off the hull....
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SailorGreg

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Re: Nottingham J class build
« Reply #21 on: October 23, 2017, 02:52:57 PM »

 Lately I have been sticking planks on the deck.  This is mostly straightforward as the lime strips bend easily to the curve of the deck and the wood cuts nicely where fitting around hatches is needed.  The only hiccup happened when I discovered that a couple of the strips hadn’t been cut properly, and one end was narrower than the nominal 5mm (pic 1).  Unfortunately, I only discovered this after I had stuck one of the wayward planks in place,  >>:-( so I spent a while digging it out and trying not to damage its neighbour too much.  I had bought 50 of these strips and only two were dodgy, so I will just put that down to experience.  But I did do a quick check on every strip before using it from then on.  O0


Another lesson I (re)learnt – keep the hull covered to protect it.  I had removed the plastic covering the hull when I floated it to get the mast tube vertical, and the masking tape around the top of the hull went when I sanded the edge of the ply deck flush with the hull.  I started planking the deck with no protection on the hull and pretty quickly left some glue smears from sticky fingers on the pristine surface.   >:-o There is now a layer of tape over the hull again!


Pic 2 is a shot of the planking progressing.  Mostly this went quite quickly although the cutting to fit took a while, as I got it wrong at least once on many of the fitted pieces.  Some of the gaps needing filling were quite small, pic 3, and there is one small piece that isn’t glued in place – I test fitted it and couldn’t then get it out to add glue.  It will either stay there for ever or fall out at some point, when I will just glue it back!  I am glad I didn’t try and do paper caulking as I think I would have given up in frustration with the smaller pieces (although xrad’s suggestion above might ease that particular problem).


Once the planks were all in place, I scribbled lightly over the whole deck surface so I could see where the low points were when I did the scraping and sanding, pic 4.  I then scraped the deck using Stanley knife blades, pic 5.  Scraping removes material more quickly than sanding, as it takes shavings rather than just making dust.  It also leaves a nice smooth surface.  I did resort to sanding in the confined areas between the hatches where I couldn’t wield the scraper very well.  The finished deck is shown in pic 6.


In parallel with planking the deck, I made a start on the hatch covers.  These are an option from Alan Horne, the hull builder, which I took.  The first thing to do is to build a frame around the hatch coamings, then start adding the laser cut pieces.  Pic 7 shows the main hatch mostly complete and the bare frame formed around the rudder hatch, with the constituent pieces lying to the left.  I felt the ply was a little too bare for my taste so I bought some mahogany veneer and clad the hatches with it.  Pic 8 shows the main hatch partly clad.


The hatch kits have bars over the “windows” formed from thin brass rod. There are a fair number of these to cut, so I made a jig from scraps to make sure they were all the same length.  Pic 9 shows the jig and pic 10 is the hatch with the bars in place.


Although the deck is finished, I am pondering how I can finish the deck edge.  At the moment, the edges of the ply and the mahogany margin plank are showing.  I would like to cap them with a gunwhale strip both for neatness and to give a small degree of protection to the hull.  Can’t decide exactly how to do that without risking (even more) glue smears on the hull.  Watch this space!


Keep those sticky fingers under control!


Greg

 

Ken the Polish

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Re: Nottingham J class build
« Reply #22 on: October 26, 2017, 05:35:31 PM »

Hi Greg, I have just joined M B M . I was extremely pleased to see your extensive notes and pictures re your  current build of the J class. I am due to purchase the kit very shortly. Reading your articles has certainly been very informative. Good luck with the rest of the build. Regards Ken .
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SailorGreg

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Re: Nottingham J class build
« Reply #23 on: October 27, 2017, 06:36:09 PM »

Welcome Ken. I hope you enjoy building your J as much as I am. I am certainly no expert but if you have any questions, do ask. And a build log here on Mayhem would be most welcome!


Greg

SailorGreg

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Re: Nottingham J class build
« Reply #24 on: November 02, 2017, 06:18:05 PM »

 Isn’t it funny how some of the little details seem to take up the most time?  I mentioned at the end of the last instalment that I wanted to fit a gunwhale strip but wasn’t sure how to do it.  Well, after much umming, aahing and head scratching, here is what I did.  I will leave out all the agonising, mind-changing and self-doubting so it will appear that I went confidently ahead with my plan!  :D
 
I had a piece of hard maple that had been hanging around for a while so I decided to use that for the gunwhale.  I reckoned the finished piece was going to be 2mm thick and 3mm top to bottom (the same as the thickness of the deck and mahogany margin plank).   I sawed and planed and sanded some 2mm x 3.5mm strips from the piece I had (my thickness sander was invaluable here, but I could probably have bought ready cut strip if I needed to).  I planned to fit the strip bottom edge flush with the boundary between hull and deck than sand off any that stuck above deck level to get a nice even finish there. The trickiest part was going to be the stern area with that nice curve to be reproduced, so I tackled that first.  If that didn’t work, I wasn’t going to bother with the rest!  I made a mould to represent the stern and steamed a piece of the maple strip in the microwave.  Quickly pushed into the mould and clamped up, I had a piece that was pretty well the same shape as the stern.  Well, eventually I did.  %)   Pic 1 shows the successful piece clamped in the mould and one of my several failures.
 
(Steaming in the microwave was something I had read about but never tried.  For my final successful attempt I wrapped the strip in a piece of kitchen towel held with masking tape, soaked it in water and put it in a (unsealed) plastic bag.  On a plate and into the microwave for 2 ½ mins on full power.  Take it out (wear gloves!), quickly into the mould and leave until cold and dry.  It took me a little trial and error, but I am still allowed in the kitchen.  ;) )
 

Once I had the curved piece, I stuck a piece of scrap ply onto the stern with double sided tape to act as a base to locate the strip, with a piece of thin card sandwiched between scrap and deck to allow for the extra 0.5mm thickness of the strip.  The stern was supported on a couple of cork sanding blocks so the weight of the hull kept the piece of scrap firmly in place as I pushed the strip against it. I fitted the strip with CA, starting at one end and working my way around the stern until it was all fixed in place, pic 2.  I rounded off the bottom corner of the strip before fixing.
 
With that successfully out of the way, the long straightish bits were much simpler.  Before gluing, I put some masking tape precisely along the top of the hull to stop the glue from getting on the gel coat, pic 3.  You can also see that, following a rather heart stopping moment   :o , I have tied the hull to the back of the bench to keep it where it should be!

 
The strips (also with bottom corner rounded off) were simply butted up to the squared-off end of the stern strip and glued with waterproof wood glue (Titebond III in this case), held in place mostly just with masking tape strips, pic 4.  You can see that I am taking no chances now with protecting the hull from my sticky fingers.  Pic 5 shows the second piece in place and a trial fit of the mast tube. It's tall!   :}
 
Not much to show for a lot of faffing about, but I am much happier now with the appearance of the boat.  One point I should make – if you plan to race one of these boats seriously (I don’t), I suggest you check with a measurer that these gunwhale strips are acceptable.  Strictly speaking they make the beam of the boat greater than the allowed dimensions.  I seriously doubt they give any performance advantage, but do check.
 
Oh, and the sails arrived yesterday from Nylet.  They look lovely – and very big!   :}
 
Happy modelling


Greg

 
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