I’ve always been in love with scale sailboats, since I was a kid I’ve tried to build some, some of them successfully some others not at all. The time passed quickly and now that I finished college I want to try again. This time with a model not so hard but nice enough and I found these plans of machichaco sailboat which I think are pretty detailed and complete. I would like some help from you before getting started.

First of all, the size of the boat. I would like it to be about one meter in length. Which size do you recommend me for a boat like this one?
As I am an engineer I will start by making a 3d model of the boat. I am solidworks professional so it will be easy for me. I also own a laser cutter which I think will be helpful. I am planning to build the boat with balsa because is very easy to handle and very light also. Once I finish the 3d model this post will serve as a build log. Hope it will be interesting for you.

I am from Mexico but now I live at Prague, right in front of the river and I do not want to miss the opportunity to sail there.

Your picture certainly shows an attractive yacht reminiscent of the IOR designs of the 70’s / 80’s. In terms of an appropriate size for your model I’d of thought 1m a minimum and to ensure good sailing performance would consider something around 1.2 - 1.3m. Reasoning? To maintain true scale dimensions you really need to consider displacement to allow maximum possible ballast without the finished model floating to far below her LWL. Alternatively, keep her to scale above the waterline but consider the use of a deeper fin and possible ballast bulb to maximise righting moments.

Good luck with this project and I look forward to reading / seeing pictures of your progress.



Hi Juan,

looks similar to an Optimist from Graupner
(a nice boat that performs very well with a homemade lightweight rig and a well trimmed set of sails):

1 m+ should be ok.
If you consider to build (semi-)scale beneath the LWL, be prepared to reduce the sail area depending on the wind conditions.
You could use several rigs in different sizes or something like this:
(sorry, wrong language but with pictures)

On a river with currents, try to sail around the weeds and plastic waste (or try a longkeeler :wink: )

Best wishes

Thanks for your comments Row and Wolfgang, your advice is very helpful.

Now considering what you have told me I think I will build the boat at 1.3 meters. Also I will think for a good solution about the sail area reduction and the LWL issue.
As you point out Wolfgang the ship is very similar than the optimist from graupner, is a shame that they no longer sell those kits, it would be a better option. I also like a lot the atlantis from robbe but is discontinued too.

I hope my project to be succesful but theres a lot of things I need to learn first. Could you recommend some book or article or something? something that talks about all the things you need to know about rc sailing.

The place where I pretend to sail:

I found the ‘how to ?’ forum quite usefull:

Perhaps some local support:

Thanks Wolfgang
It seems i have a lot of material to study jeje
the minisail site is pretty interesting, unfortunately I do not speak Czech

BTW: I just realize this sailboat includes a motor, I just see the propeller. It is small, that’s what I haven’t saw it. Do you recommend me to include it? or keep the boat entirely as a sailboat?


Little progress: Render of the 3d design, I will add more as I advance

Juan Carlos

On a River with reasonable currents, yes … :wink:



(without motor and wind :wink: )

Hi wolfgang
Thank you for your help. May be I should find a more suitable place to sail than the river because is something goes wrong it will be hard to recover the boat. I will search for places where czech people sail.

If you want to see another example of ‘True’ scale sailing boats, have a look at the following link:

If it raises any questions you can register with the site and ask builder - I’ve been in touch with him a few times & he’s always been incredibly helpful.


Thank you twister for the info, I was very busy at school so I had not time for models but now that I finish I can work on my sailboat after work :slight_smile:

I am deciding if I will continue to this machichaco model or not but anyway all your help will help me with the sailboat I choose.


Finally I decided to continue this project, right now I am assembling the hull. I will post pictures later. So far is looking good (to my novice eye). I am excited cause i always wanted to build a proper sailboat and it seems like it is time to do it now. I have built two sailboats in the past, one rg 65 and one that I design, actually very simple one. This will be my first scale sailboat.

It’s been a while since my last post but here are some pictures of my progress.

Right now I am not sure if I am on the right path. I laser cut all the parts and glue them together but I might made the keel too thick. Perhaps it is good and just needs some sanding. Not sure.

What do you think? I am afraid I might need to start all over again

The frame measures 1.1 meters in length


Looks good! If your design is modelled on a full size design I’d be inclined to try and keep the thicker keel (assuming the proportions still look ok) for the simple reason that it will allow either the ballast to sit lower or enable you to carry a greater volume of lead etc for improved righting moment.