J-class Lionheart, in 1:24 scale - a new frame set ready to cut

rshousha

rshousha

Joined
Dec 22, 2023
Messages
81
Points
88

Location
Montreal, Canada
As some of you many know, I am a designer of frame sets for large-scale R/C models. One of the classes I design is the large 1:16 scale AMYA J-class. These measure between 97 inches and 107 inches. and the class allows a 10-foot mast. These are quite big and require a dedicated work area as well as special transport to get the boats to and from a sailing area.

Over the years, I have been asked numerous times to design a smaller version of these great yachts. The problem was to create a size that could be built in a typical workshop, but that would also continue to have enough space inside in order the fit servos for steering and sail trim. This is an issue with these models, as the overhangs on the real boats are huge and scaling that down means there is little room at the bow and stern for R/C equipment.

I decided to go with 1:24 scale in order to meet these needs as much as I could. I have also added a few of my own design features to make these boats easier to build and sail.

I have decided to do Lionheart first, as she seems to be the most popular yacht in the class. At 1:24 scale, Lionheart works out to about 71 1/4" LOA.

First order of business is to get a nice 3D shape for the hull. In the "old days" I would use some sort of line drawing to trace out the frames right into a manufacturing software. This method is now quite obsolete. The frames are now traced into a dedicated 3D program that allows us to create a fair hull shape. This shape is then inserted into a manufacturing software in order to create all the internal parts, which are then used to make the laser-cut, or CNC-cut, manufactured parts.

As I feel we have way too much plastic in the world, I do not give away the shape in digital form for 3D printing. A builder needs to build this model out of wood.

This picture shows the beginning of the process. The hull has been created; the keel has been drawn, and a few bulkhead shapes are inserted. All parts will be cut in 1/8" plywood.

PROGRESS-FRAMES-2024-8-6.jpg
 
rshousha said:
As I feel we have way too much plastic in the world, I do not give away the shape in digital form for 3D printing. A builder needs to build this model out of wood.
Click to expand...
I am VERY anxious to follow your project. Will the drawings be useable and available to build a 1:48 static model that would replicate the actual yacht, including things like the shape of the mast and boom, and deck furniture? Something similar to the pic below is what I envision. Does the actual yacht class have aluminum hulls? I like the idea of wood, and there would be a lot of hours on the finish work which I find therapeutic at times.
THANK YOU FOR SHARING YOUR PROJECT!
Allan
1724111782438.png
 
Hi Allan,

Thank you for your enthusiastic response. Sometimes, toiling away behind a computer screen, one wonders if anyone out there is listening.

Sorry, I don't have plans to make 1:48 scale versions of my models. I do agree that would make an interesting size for a static model, but I design pretty well strictly for R/C sailing and a 1:48 scale model simply doesn't sail well. As you can imagine, one cannot scale the wind, so a 1:1 scale wind of 4 knots (very light wind, indeed) would scale to 96 knots on a model built at 1:48 scale. It would have to have an enormous keel to keep it upright, relatively speaking, and so the hull itself would have to be very, very light in order to keep the waterline more or less at the right spot.

Really, the smallest scale I can think of is 1:24 for R/C sailing. Even at that scale, I have had to increase the keel considerably in order to expect the boat to sail in the lightest winds without sitting on her ear.

Now, on the other hand, if you wanted to build this model is 1:24 scale, as I am planning then, yes, I will have the deck structures and some 3D printed parts such as winches and dorade vents included.

The AMYA class allows fiberglass as well as wood. I am not sure one could build in aluminum. This model is a new idea that I have had and I hope to design the frame sets for several of these wonderful boats, but I think I will continue to design them with the intention of having them built of wood.

My specific reason behind designing for wood construction is strictly environmental. We do not take our toys with us, and I would prefer that our toys disappear soon after we are gone. In my several decades of trading in models, I have rarely seen a model be enjoyed to its fullest for more than a generation or two.

Regards,

Rick
 
rshousha said:
The AMYA class allows fiberglass as well as wood. I am not sure one could build in aluminum.
Click to expand...
Back in the 70's I worked for PPG Coatings and Resins division in Torrance, California where I learned how to work with gelcoat, glass, and laminating resin. I built a plug of an Islander 36 hull and another for the deck structure. Next was make the two molds, then make the actual hull and deck structure using the molds and glass them together. Being allowed to take home the materials from our factory that I needed, it worked out very nicely. Wish I still had photos.

Regarding scale, on a few occasions I have taken plans drawn to one scale and had them increased or reduced at architectural design shops for a nominal fee so if you make them available at any scale I would be thrilled. My only concern is can I work from 3D drawings to hand make things such as the winches, et al. I am all for 3D printed parts for some things, so this could expand my horizons. I look forward to your progress and thank you for sharing your work with us.

Allan
 
AllanKP69 said:
if you make them available at any scale I would be thrilled
Click to expand...
Hi Allan,
I absolutely love making nice drawings. In fact, it's what got me interested in learning CAD in the first place. However, I am quite far behind in the design of parts and frame sets. Let me see how things go as I move through this project. If I can squeeze some time out to make some decent drawings, I will do that.

Regards,

Rick
 
I've added a few more parts to the model. Now, the bulkheads are all done and opened up. Note there are extra bulkheads at the mast.

Next we need to add the T-rail to simplify construction.

PROGRESS-FRAMES-2024-8-8.jpg
 
Onwards.

I have now completed the frame set for the Lionheart, in 1:24 scale. I will continue, at a later date, with 3D-printed winches, dorade vents, and a few cleats. I will also design a display cradle. But, for now, a builder can start the construction.

The pictures show:
- an exploded view of how the assembly should go together on the build board
- the little mast track support surface
- a couple of extra surfaces at the stern to aid the builder to get a nice shape back there
- the waterline stretchers

Now, it's time go find some builders!

EXPLODED-VIEW-2024-8-16.jpg

MAST-TRACK.jpg

STERNPIECIES.jpg

WATERLINE-STRETCHER.jpg
 
Hi Allan,

Since small-scale kits are no longer supposed to be on my "to-do" list, how about if we changed this up a bit and did a cross-section of a J-class boat in 1:16 scale? I could do the central section easily enough and I could include a cradle and part of the deck structures which I have already designed. I also already have the winches and air scoops done for Rainbow, for example. I also have some really nice deck houses done for Lionheart.

What do you think?

Regards,

Rick
 
I too admire the work you're doing. I haven't read about this approach since the 60's seeing it in periodicals on ship design. Beautiful!
 
Hi Rick
Anything you think that will allow any of us to build a J Boat model in detail will be welcome. Lines drawings are available as you know, but the devil is in the details as usual so whatever you think would help would be very welcome.
Thank you for very much
Allan
 
Hi Rick,
I fully agree with the fore speakers: You are taking on a difficult subject and doing a superb job!

As an absolute novice to wood models and ship building, in general, I was immediately fascinated by the lines of the J-class yachts so I'm definitely going to tackle one someday. As nice your design looks, 1.8m are simply not fitting my building area nor the display space I'm willing to spare but I will sure be a first row viewer when a build log is going to be published of this beautiful design! Please do keep us posted on the progress!

Do you have a website when we can have a look at your offering?

Warm regards,
Cristian
 
Hello Christian (and others),

While I do agree 1.8 m, or more (some of my designs are around 2.6 m), are large, it is quite difficult to scale the wind! And so, if I want my models to look at all scale while sailing in a typical breeze of 6 knots, say, I need to create a balance between the actual scale of the model, and the shape we would need to keep it upright. Imagine a 1:48 scale Lionheart would be seeing an effectively 288 knot wind across the deck! So, in order to keep such a tiny vessel upright, one would need a completely oversized keel. This works for real R/C sailing models, where the design intent is to sail them in any conditions. In my case, my interest is to design models that are close to scale, and so I try and keep the underwater shape somewhat similar to the original.

There are exceptions, of course. In my Friendship Sloop, my Malabar VI, and my Cat Boat, I have an internal structure that will accept external ballast. However, even in those models, the external ballast is designed to be removable so that the model can be displayed on a cradle that allows it to have a very scale model appearance.

Again on the question of size, I have had a lot of interest in making smaller designs, and that is why I have done a couple of powerboats lately. My Maltese Fishing boat is certainly my finest model so far, but the new Charles Mower design I am working on should just as nice.

If you want to see some build logs, they are available through links on my website, and also on a site dedicated to remote-control modelling.

My website is at www.modellers-workshop.com

Cheers,

Rick
 
Thank you! The hobby business sure is changing. I now have three orders on hand for custom 3D-printed parts. One of them is for a project worth almost $20k. I am slowly changing my business from a retail company to a design-oriented manufacturing business, specializing in large-scale R/C models. There's really no one else out there focusing on large-scale models and I do think it's quite fun to see a model come to life once it's built. So, between making 3D parts, and frames for large-scale models, I think this is going to be a good business.

Also, with the average age of a modeller increasing, and vision becoming an issue, I think it's important to offer models that are easier to see.

Cheers,

Rick
 
You must log in or register to reply here.
Back
Top