Great explanation of the process for producing the shapes needed for the stem and the molds. The main lines, water, buttock, station and diagonal, are really the easy part to get on the board. It is the details of bevels and relative plank thickness that seem to throw me for a loop so this was a very nice lesson. Just glad it is on video so I can watch it several more times until it sticks. Thank you Mark and thank Mark who demonstrated the loaf of bread concept of lines. Take care and have a great week ahead.
@@Nomadboatbuilding Where do you get your tools? I saw the video of you making the model, and you had tiny planer. Where do you get your planers, saws, etc.?
I have watched Ian Smith's vids on lofting and this one. It is a very confusing system. I understand its usefulness for ensuring the full size drawings are fair before the first mould is cut and that it is possible to get the transom shape; but I wonder why the planks are not just fixed over what is an already accurate set of lines. I am sure there are good reasons and I may eventually get them if I study enough, it seems a bit too much to take in at the moment.
I can totally understand your confusion. The main reason we don't just lay planks over the moulds is because most plans have been designed and drawn to the outside of the planking. From a designer's perspective it just makes the most sense. It lends itself to working out aesthetic details and calculations. Sometimes you get designed drawn to the inside of the planking and personally, I have a hard time lofting those out. Suddenly the relationships at the stem and transom become harder to visualize. There are plenty of builders method workarounds though. Historically builders would make a half model, pick of a few points to draw some moulds full size and use battens to juggle it all into place after the moulds were made. I imagine they rarely worried about plank reductions. Lofting isn't an absolute requirement to boatbuilding but it can be a valuable tool when specific results are desired. Until you try it, yes, it is confusing. But with experience the fog will eventually lift. I still refer to Howard Chapelle or my old boat-school notes every once in a while.
@@Nomadboatbuilding Pretty much what I expected about keeping the lines by reducing the moulds. I have full size acetates for the Ilur I am building, so the lofting is already taken care of. I feel sure that the more I do, the more I will understand and also know the right questions to ask. Thank you for taking the time to reply.
The bevels between one station and the next would change depending on the elevation, wouldn't they? How many points do you take along the station to determine the planking offset? I really enjoyed your explanation. Very clear. Thank you.
The bevels between on station and the next change relative to any reference you use. That's just the nature of these shapes.The only time they might stay almost the same is in a shape like a cargo ship which is little more than a shoe box. There is no fixed number of points i use along a station. It has more to do with the consistency of shape. If two stations have lines that obviously run very parallel to each other, the bevels are probably going to stay roughly the same so fewer points are required. The main thing is that you pick off enough points to control the fairing batten that you will use to redraw your reduced station lines.
Somehow mixing dimensions from inches and millimetre invites mistakes. I really don't understand why you want to do that. One other point: Seems to me a waterline isn't fixed at all. You can't rely on a waterline that might not be true. Volume is a given depending on suppositions of a weight after a boat is built. All you can do is guesstimate what it might be.
You are quite correct about mixing measuring systems but my brain works in imperial and the plans are in metric. I use metric when referring to the plans and imperial when building from my head. It’s easier for me to visualize imperial which is why I am often converting but I agree it isn’t without its pitfalls. Waterlines are always estimated and in larger craft are often ballasted to meet the estimated waterline after construction. Best you can do is to try to build as designed if you hope to meet that waterline mark.
Fernando Fert yup. Sorry. That stuff just doesn’t show up well on camera. Drives me crazy. That’s why I haven’t done a full nuts and bolts lofting video.
Haha. I’ll have to check that out. I'm convinced you pretty much have to do it with 1/4” wide sharpie to make it show on camera. I'll just have to commit to producing a totally useless lofting in order to make a show of it.
Edward Barker I wish I could magically do that for you but I’m afraid that ship has sailed for this video. Sorry about that. I’m afraid this project has to march ahead and the camera work comes second. Not everything works out for the best video wise. Hopefully I’ll get to a point where I can do a spec build that is for the benefit of the camera. I do use coloured pencils when I start working out patterns and such but they don’t erase well so I don’t use them for the initial lofting.
Apologies for that. Lofting is very difficult to film without using heavy sharpies to make the line show up but that makes the drawing useless to build from. Obscure, perhaps but it was just intended just to give you a taste of the process. The beginning of my Bouchie Dory series walks you through the basic lofting process in simple step by step terms and the lines are properly visible. Maybe have a look at that if the subject interests you.
