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jonny.amy

Gone, but not forgotten
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About jonny.amy

  • Birthday 07/18/1992

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  • Gender
    Male
  • Location
    Southampton, UK
  • Interests
    Interests include: Sailing, Kayaking, Rowing, Naval History, Playing Electric & Bass Guitars, Playing in a Band, and building scale models

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  1. I can't help it! I've always fancied building one of these... I just can't get the boss to get on board!
  2. Keith, I think the tension of the outhaul / lack of outhaul in the aforementioned pictures could be based on three aspects: 1 - In Photo 3 - lack of tension is because of the use of cruising sails (a lot of these yachts will own multiple suits of sails, at least 1 set for cruising and deliveries, and possibly 2 or more sets for racing in various wind conditions), these would be a synthetic canvas material for longevity and robustness (last thing you want to do is rip the canvas sails with charter guests aboard), and would probably be cut to give ample shape to the sail for a short handed delivery crew or charter crew to get the best boat speed. 2 - In Photo 5 - the outhaul is tied off to the cleat (top left corner of picture) and coiled away (also top left). This is probably due to the (again) the use of cruising sails? Tell me, are these pictures taken from a promotional charter website/video/photo gallery? I've done fair bit of charter work as crew, and the mantra for most boats is "keep it simple" - 90% of Charter guests are not interested in the sailing aspect of the charter (mostly the looking good one a good looking yacht thing), and the yacht will be sailed with a small crew (usually a Skipper, Bosun and 2 Mates), so sailing her needs to kept simple. 3 - In Photo 1 - Just because the sail is full, it doesn't mean you have to have an outhaul running all the time. Photo 1 shows two short lashings at the boom end-cap, which suggests to me that the crew have removed the outhaul in place of the lashing. The natural stretch in the rope lashing would allow for some ease of pressure, whilst retaining a constant pressure and curveture on the foot and luff of the sail. Again, I assume that these are candid cruising shots, so she isn't fully powered by up in all of her racing fit out (read any Supersail World magazine and that will highlight the fact that all of the yachts have a cruising and racing set up for their rigs). I'm sure Photo 2 also covers this use of lashings. I hope any of that helps, and I would suggest that the outhaul is a roving line that only comes out in full force when racing or on very long distance sailing. I would also speak with Fairlie Yachts on the Hamble River to see if the current rig is as per designed, or has been optimised for the current owners requirements. Its is also noteworthy that Fairlie did the restoration of Altair in 2004/2005... https://www.fairlieyachts.com/ Cheers, Jon
  3. Keith, The line that runs under the boom and terminates at the winch is almost certainly the outhaul. This is the most logical place for the outhaul to be, and most of yachts I've sailed on have had the outhauls running through or along the boom to a clam cleat or jammer, and then on to a winch at the base of the mast. The outhaul terminating on a captive winch on the mast allows for crew to make small or large adjustments to the tension in the sail when required whilst keeping the pressure in the sail (which in turn keeps the yacht on course), and keeps weight in the center or slightly off-center (to windward) when adjusting the sail tension. The picture shows a crew member adjusting the outhaul, and a crew member on the winch to grind the winch. As far as I'm aware Altair is one of only a few classic yachts that still use the classic canvas sail material and not the modern equivalent that has a lot less stretch in it when under pressure. The crew will be adjusting the outhaul to match the wind speed and pressure (in this case its a light breeze) so they can gain the correct shape in the sail. To help with sail shape, on modern racing yachts, a tweaker block is set up with the main sheet. I'd hazard a guess at the two lines in question attached to the underside of the boom are tweaker lines for fine tuning of the main. It would allow for additional twist in the sail when heading to windward and would eek a few additional fractions of a knot on that tack. In this example, by bringing the leeward (in this case, port) tweaker line done by a few inches you could add significant twist to the sail and increase their boat speed. Likewise, in the event of a large gust or squall hitting the yacht whilst hard pressed to windward (likelihood is that the yacht is trying to fetch to the windward mark in one tack), by easing the tweaker line on leeward side would dump about 40% of the power from the sail, meaning you avoid being hard pressed and potentially rounding up. The tweaker lines are mostly used whilst sailing upwind or reaching, but can be used to achieve finite adjustment of the sail whilst sailing downwind. Just my two cents, but it seems logical that it would be a tweaker. Cheers Jon
  4. Gaetan, First of all, I'd like to say that this is an amazing project, and the scale you've chosen is very admirable! I'd love to have the space to build a 74, let alone a 74 at 1:24!! I've been watching this build log with awe and a slight bout of the "green eyed monster"! I build and paint in the lounge/diner of my 1 bedroom flat, so I'm used to working with the tv on in the background. I find I can focus better with the background noise because I'm consciously blocking out the noise (this has been described by the Admiral as "Boat Brain"). I find music is too distracting as I tend to hum or sing along and then break focus. Anyway, well done with this AMAZING build, and I can not wait to see the 74 progress further. Cheers Jonny
  5. Hi Chris, My experience with airbrushing is limited (I am relatively new to the whole airbrushing thing), but the area of paint applied will be directly dependant on whether or not you thin the paint. I'd suggest reading around and finding out the best thinning ratios for the paint that you are using and then buy an extra pot of the paint to test your thinning ratios. I've been thinning Gloss White with 2 drops of White to 8 drops of thinner. This makes a very wet paint that is applied, but dries very quickly and then can be re-coated fairly soon afterwards. If you buy a cheap plastic model (best to work on something similar to your final project) you can see how the mix ratios then react with rounded surfaces such as the tumblehome of a hull. Cheers, Jonny
  6. Clare, I started HMS Wolf back in March and have been working on it as a sideline project. I didn't start a build log because I've been fairly busy developing a comprehensive 3D CAD model of my Grandfathers yacht to 3D print and present to him on his 80th Birthday. I've managed to get the hull of Wolf to a reasonable level of completion, but as it's my first paper kit, I've probably made avoidable mistakes on the kit. I'm considering bashing the kit even further by 3D printing a number of item such as the 3 lb guns and 1/2 lb swivel guns. As for Victory, I recieved the paper kit for my Birthday in July, and was surprised to find that not a piece of card was supplied with the kit to build up the "skeleton" so all I've managed to do on Victory is cut out the main spine and roughly cut out bulkheads 1 to 5 & 16 having glued them to 1mm thick Artist Mount. I have another 19 bulkheads to cut out, and then the intermediate/lateral support and deck pieces. So there is a lot of ground work to do before starting a build log in full force. Once I have the yacht off the desk I'll start a build log for Wolf and Victory. Cheers Jonny
  7. Clare, I'll tag along too!! I'm building HMS Wolf and HMS Victory (both paper rather than card) at the moment - must say I'm quite infatuated with these kits! They're very fun and quick to build! I'm thinking of buying Mercury too, but will have to wait a while I think. Cheers Jonny
  8. I think I would also like to see a POF model of e.g. a British or French 6th Rate in a reasonable scale (1/64 or 1/48) available to buy in 3 "Modules": Bow, Midships and Stern. I'd suggest each section be similar in size and each module could be bought for sub $200, so that the work could be phased and planned to suit building a model of reasonable size. That way one could build a 28 gun Frigate without the masses of space required (for example a dedicated room/garage/hobby shop) and tools to build a a full POF model. This would also allow each model to be sold by the manufacturer individually or as a bundle with a slight reduction in price, for example $200 each or $550 for "Modules A, B, & C". Just a thought....
  9. I'd like to suggest a more obscure type of vessel - this is a Merchant Brig circa 1795 bought in to the Royal Navy to test Centerboards / Drop Keels on larger vessels. This design was developed and investigated by John Schank. http://collections.rmg.co.uk/collections/objects/66542.html The National Maritime Museum says: "Schank entered the navy at a young age, and was known for his skill in ship construction and mechanical design. While he was a lieutenant in 1776 he was in charge of assembling ships to battle the American Revolutionaries on Lake Champlain. He constructed HMS 'Inflexible', which he also commanded as part of a fleet that defeated General Benedict Arnold's fleet in October 1776. He was made a captain in 1783, and bought his design for ships with sliding keels before the Admiralty, which was incorporated by the Admiralty into ships. In 1821 Schank attained the rank of admiral of the blue". Scale: 1/64th to 1/32nd Size: Max. 800mm Period: 1750-1900's. Nationality: Don't care Building method: POB or POF: POF preferred if laser cut (consider POF method used for Longboat and Pinnace as 'easier' introduction to POF building??). Materials: Basswood / Lime - not Walnut (unless it has a very fine/even grain) Cost: sub $500 inc. shipping to mainland UK/Europe.
  10. Hello Chaps, It's been a while without a post on the Westerly Discus... Home life and work have been incredibly busy over the last month or so, and with the nicer weather and lighter evenings, it's been very hard to sit down at the laptop and work on the Discus after work when I could be out enjoying the nice weather with the dog. Problems with 3D Modelling Pt. 3: DelftShip: So I left off discussing the problems I was having AutoCAD to produce a comprehensive 3D model of the yacht, specifically modelling the bow and stern with accuracy, so whilst talking with my boss about the problems I had encountered, he suggested using DelftShip, a free 3D design package used to design Ships Hulls (my boss spent 20+ years in the Ship Building Industry as a Draftsman) and with gave me a brief run down of how it worked (admittedly he hasn't used the program in a number of years). So following the sound advice that had been imparted on me by him, I went home and downloaded the free version of DelftShip. The first piece of advice I was given by my boss was to import the lines drawing (provided by Barry van Geffen) in to DelfShip as a .dxf file, but in the free version, this is not possible, so I had to try to create a copy of the hull based on the basic hull shape generator built in to the program. This would have been a suitable method of producing the hull shape if I had a Table of Offsets to work from, but unfortunately, I did not think I would have this issue whilst I was in contact with Barry from Laurent Giles, meaning I had to try to recreate an accurate Table of Offsets from the drawing provided. Upon further investigation in to the functions of DelftShip, I found that I could input a Table of Offsets in to DelftShip and produce a hull shape from that. Unfortunately, I found that this did not work on my version of DelftShip. This drew an end to my investigation in to the feasibility of 3D modelling the hull in DelftShip. Autodesk Inventor: After this, I decided I would search the internet for the best method of 3D modelling a yacht. I found an number of Autodesk users describing 3D modelling of yachts and ships in AutoCAD Inventor. Reading further in to yacht design with Autodesk Inventor, I found that it could be done, and the design could be manipulated to produce a 3D printing file. Taking in to account that Inventor is completely different kettle of fish to AutoCAD, I decided I would take this slowly and start building a cube, and adding chamfers, fillets, fittings and penetrations to the faces. After a bit of time, I thought I had cracked it, and I decided I would try to model the yacht in Inventor. Once again, I severely underestimated the complexity of the hull shape and soon came to the realisation that I did not have the skills required to model such a complex hull form in Inventor. Bentley MicroStation: Feeling rather down-trodden with this realisation, I decided I would try one last 2D/3D design package that would allow me to utilise a Civil Engineering design package to create the hull form. In MicroStation there is a Topographical Modelling module that can be used to produce a 3D model of hillsides/slopes/mountains using topographical "slices". Treating the hull like an upturned hill or slope, I prompted the command to loft between the waterlines of the hull. I found this worked, but the lofted panels between each waterline were very triangular and primitive. Laser Cutting: At this point I wasn't confident I could 3D print this model, so I investigated Laser Cutting the design based on the waterlines. I manipulated the CAD drawing to include a 10mm offset on each waterline and found a number of local companies capable of Laser Cutting the model out of 5mm thick MDF. At this point I sent the laser cutting files out for inquiry and soon had a number of responses from the companies. Upon receiving the initial quotes (average price in excess of £250) from the Laser Cutting companies, it was decided that Laser Cutting the waterlines was too expensive and the required work outweighed the cost of laser cutting. This left the project dead in the water for a week or two until it was suggested by my Father to try using Google SketchUp. I have not used SketchUp in the past and have always been dubious of the quality of the 3D modelling capabilities of the software. Willing to try anything at this point, I decided I would give it a go, and downloaded Google SkecthUp 2016. I can safely say now that I was wrong to have the misconceptions about validity and modelling capabilities of SketchUp. This is very good 3D modelling package and with a fairly small learning curve, it allows the user to build high quality 3D models with a great deal of accuracy. That's it for now folks. I'll post more this evening with some photo's of the 3D model. Cheers, Jonny
  11. Hi everyone, Things have been fairly busy outside of the shipyard, so not a great deal has been done. Hopefully I'll be able to get on with the model shortly. Cheers, Jonny
  12. Problems with 3D Modelling Pt. 2: AutoCAD: So I left off with Options 1 & 2 giving very little in a way of usable 3D model, now I will discuss the other limitations I faced in the design process. Option 3 - Laying a mesh over the 3D Wire Frame - This option was a step in to the unknown for me, as I have never modeled meshes for "yacht design" before. I read around on the internet for advice, but there was very little available in regards to meshes in a complex surface form, such as a hull. Each website I looked at eventually suggested lofting complex surfaces in programs such as AutoDesk Inventor, 3DS Max, and Rhino, but ultimately, because this is project on a budget and time schedule I was not prepared to download another free trial and try to learn the software whilst working on the deliverable 3D model. With this I tried to lay the mesh over the 3D wire frame I had built in AutoCAD previously. The wire frame model was imported in to AutoCAD as DXF file (AutoCAD reference file) and the number of mesh parts was calculated. This was achieved by calculating the number of intersection between the waterlines and stations on the model. With 15 Stations and 11 Waterlines, I calculated that 165 Mesh Panels would be required. I ran the AutoCAD mesh command, setting the mesh length to 15 panels, and mesh width to 11 panels. I imported the mesh to the drawing datum point (X,Y,Z - 0,0,0), and started manipulating the mesh to fit on the wire frame. This worked fairly well around the Shear, Knuckle (Chine) and Flatter surfaces around the bow, but as I pulled the mesh elements around the waist of the hull, I found the computer started to struggle to align the flat surfaces to the voluminous hull shape. I will continue the discussion on design limitations with DelftShip, AutoDesk Inventor, and Bentley Microstation, in the pursuit of perfection. Cheers, Jonny
  13. Problems with 3D Modelling: AutoCAD: In my attempt to 3D model the yacht in AutoCAD I have come across a few problems that have left me a bit stuck on the 3D modelling aspect of this project. Firstly, the choice in method of 3D modelling, either extruding the bulkheads a certain depth, lofting other a 3D wire frame, or laying a mesh over the 3D wire frame. Option 1 - Extrusion of Bulkheads - This option is the easiest option. Taking the 2D drawing supplied, I copied the bulkheads over to a new 3D drawing sheet, where I then converted each bulkhead profile in to a Polyline. This the allowed me to use the "EXTRUDE" command to pull the bulkhead out to the depth required (at this scale, 28mm). The issue with this is the extrusion is square along the extruded Y axis, so a step between each bulkhead is then created in the X axis. This poses a problem in accuracy. The transition from bulkhead to bulkhead would require trimming, using the "SLICE" command to keep the transition from bulkhead to bulkhead as close to the design drawings as possible. This proved to be difficult as the high internal volume of the yacht has meant that a knuckle and hard chine following the Shear Line on the topsides (allowing for additional space below) does not allow this drawing command to give a precise cut on each face of the bulkhead. The images below show this problem at the three central bulkheads towards the bow. Extrude Bulkheads.bmp Extrude Bulkheads_2.bmp Sliced Bulkheads.bmp Option 2 - Loft Bulkheads over Wire Frame - This option seemed to be the most logical. The Lofting command breaks a surface down in to a number of workable points on one face. This then applies those workable points on to the new face. The example I've shown below shows a square lofting in to a circle. Lofting_1.bmp In this instance, the face of the square is broken in to 20 workable points which are then copied up to the new face (the circle) and then applied to the new face in the automatically calculated positions. This works in principle from say a square to a circle, but didn't work in practice on the hull. I found the issues with the lofting from bulkhead to bulkhead were that the program automatically optimised the lofted points without user interference. This meant the lofted surfaces were "too square" in shape and did not conform to the voluminous shape of this complex hull form. I then decided I would try to Loft from the water lines, using the 3D mesh, but again, this did not conform to the voluminous shape of this complex hull form. That's it for now, and time is marching on - I'll edit this post later on with my other options. Cheers, Jonny
  14. Hi All, thanks for the likes and comments. Mark - I hope it will make a nice model, I just have to get my head around 3D ship modelling in AutoCAD!!! Walter - I have a hard drive full of photos of the yacht so looking at those isn't an issue. The real issue is the logistics of getting to the yacht as it is in the Channel Islands (about 100 miles off the UK South Coast) which would require a flight there and back (or ferry) and will cost a small fortune, but I've been in contact with an owner of a Discus 33 of the same 'vintage' and have the option to carry out a survey if required. iMack - I am a CAD designer by trade, so this is mostly second nature to me (I plan to get a detailed description of the set backs I have encountered so far on here tonight of tomorrow). I thought my knowledge of 3D AutoCAD and 3D design packages would be beneficial to creating a highly detailed 3D printed model of the yacht. I know the concept of scratch building is to "do it all from scratch", but I wanted to obtain the highest quality from this model. Cheers for now, Jonny
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