- New files added 2-10-2017
PLAtypus (a good Aussie name!) was test sailed today 9.8.2017 in 5 - 12 km/hr variable breeze with #1 rig (80% fractional rig, main luff 850 mm, 200 mm foot on both sails) against a competitive RG65 and a DF65. Didn't lose out noticeably against the RG (apart from the stronger gusts) and equal or better than the DF. Well balanced and easily sailed in these conditions. Updates to follow, including a video. As sailed and in pic, this yacht currently has a laminex fin modified from another small yacht. The boat was left in the sun and this caused some hollows to form near the stern of the hull (PLA is a thermoplastic material). Cover the hull if leaving in the sun!!! Print using a light colour so less heat is absorbed; could trial other materials such as PLA Plus which can be heat treated in an oven (80 deg. C for 45 mins) to improve heat resistance and mechanical properties.
KEEP VISITING THIS SITE AS I AM CONTINUALLY ADDING AND UPGRADING FILES.
Uploaded pic of my nearly finished yacht 4/8 2017; added Delta bulb sections and Gooseneck/main boom files.
IMPORTANT: If you have downloaded the original files, note that the HULL, FIN, FIN CASE and MAST TUBE files have been replaced with ones to suit the latest hull design, and a DELTA BULB included which will float the hull to the designed all up weight (though with a larger surface area than a conventional bulb).
Apologies to those who have commenced printing with the original hull files which produced a hull which would not float to my designed weight of around 850g ready to sail.
If you have downloaded the hull files and have not commenced printing you can increase the volume slightly by scaling transversely say 110% and vertically 115% (hull around 104 mm wide). These figures will float the yacht at correct LWL for overall weight of around 850g.
I have now posted new hull files which will float the yacht to its designed waterline at an overall weight of around 850g. If you wish to carry more lead weight, scale the hull further in the Y (transverse) axis - scaling the Y axis by a further factor of around 117% will produce a hull of 120 mm width.
The fin/bulb weighed 510 g (only 60% ballast ratio) but a higher ballast ratio is desirable and could be achieved by using lighter booms and battery pack.
Note: The pic above does not show the recessed transom which I have redesigned for ease of fitting the rudder. Due to a number of requests for a hull design, I have posted my design for comment and printing. I have printed it, test floated and sailed it. Cut it into sections to suit your printer height, and print each section VERTICALLY (very important as it allows for no supports). You may need to design more ring frames for joining purposes depending on your printer (unless your printer can print 500 + mm high, then you can print in one piece). I printed in two sections, the stern at 270 mm long, and the bow 225 mm long allowing for a 5 mm bumper, and I have included the files for them as well as the joining ring frame I used. An extrusion width of 0.48 produces a 63g hull, 0.65 produces a 98g hull (as for my prototype). I printed the rear section on its transom, with 2 bottom layers, 0 top layers, 1 perimeter, using vase mode. The bow was printed on its large end with 0 bottom layers, 0 top layers, 1 perimeter, vase mode. Could also print with 0% infill not using vase mode. The bow section includes a dovetail to take slides for jib swivel and jib sheet. No raft or supports are needed. The fin box slot and deck opening are located for you, as are positions for conventional and swing rigs and the rudder tube (CAD and 3D printing gives perfect alignment !!). I have now included other fixtures such as fin box, jib slides, rudder, fin, hollow bulbs ( fill with lead shot/resin mix), curved boom, boom ends, boom band, rudder top spigot and bow plug. I have not included servo platforms, or battery or receiver boxes which you will have to determine sizes for. This should give those interested something to start printing.
Some more info can be found on Wollongong Model Yacht Club website (WMYC - see Brian's Stuff). Enjoy.
Designed to print in vase mode (hollow) without any supports. You can scale it horizontally/vertically to suit the overall weight you want to float (I use Slic3R to do this). This is an ongoing project so there will be minor changes from time to time. Printed using PLA with no heated bed, just a glue stick.
205 deg worked for me.
How to print the components:
JOINER - 2 bottom layers - 0 top layers - 1 perimeter - vase mode - 0% infill. This is the joining ring frame to suit the two hull sections I have posted. Cut out most of the printed flat and don't forget a small hole near edge at bottom to allow any water to drain to the back of the boat. Glue into rear half first.
BOW PLUG - 2 bottom layers - 0 top layers - 1 perimeter - vase mode. Glue in place.
RUDDER - print vertically on top end - use raft - 0 bottom layers - 0 top layers - 2 or 3 perimeters - 0 infill - suits 3 mm carbon rod for shaft.
FIN - print vertically on top end - on raft - 0 bottom layers - 0 top layers - 2 perimeters - 0 infill. Glue a tapered CF flat 8 or 10 x 3 mm down inside for stiffness (you might not be able to print this depending on your printer height).
FIN CASE - on large end (which is the top surface) - 2 bottom layers - 0 top layers - 2 perimeters - 0 infill. Fit down through deck cutout, trim to size, glue in place aligning with rudder tube.
JIB SWIVEL SLIDE - print on smaller flat surface - 2 bottom layers - 2 top layers - 2 perimeters - 100% infill - fit dacron cord through csk hole, tie knot and a loop at the top end. Position in dovetail slide using tape.
JIB SHEET SLIDE - print on larger flat surface - as above (no cord).
BOOM - Print vertically on end - use raft - 0 bottom layers - 0 top layers - 2 or 3 perimeters - use infill say 30% - cut length to suit
BOOM END - on largest end vertically - print solid (100%)
BOOM BAND - print on largest flat surface - solid - use for jib swivel, main and jib sheeting, sail clew attachment.
RUDDER TOP SPIGOT - provides a bit more support for top of rudder post - glue in place.
BULB ( torpedo shape) - not to scale, you will need to experiment to get required size - cut in 2 to suit your printer - print vertically on cut ends - 0 bottom layers - 0 top layers - 2 perimeters - 0% infill - fill with dry lead shot to achieve weight required, then mix shot with resin to fix in place in bulb. Bulb can be scaled if you don't like my length/diameter ratio.
BULB DELTA shape - gives approx. correct weight when filled with lead shot; depends on weight of your electronics, servos, rig etc - cut in two to suit your printer - print vertically on cut ends - 0 bottom layers - 0 top layers - 2 perimeters - 0% infill - lead shot as above. Again, you can scale the bulb to alter its weight.
I have now included the .stl files I used for the front and rear delta bulb sections. Form a hole in each piece at the join bulkhead and fill each with small lead shot before gluing together
MAST TUBE - print vertically - 3 bottom layers - 0 top layers - 2 perimeters - 0% infill - fit and glue into hull at printed points just in front of fin box. Drill 1.5 dia locating hole on bottom of hull to help accurately locate as bottom of tube has a locating hole. Tube is tapered to allow some mast rake. Suits 5 mm dia. CF mast.
GOOSENECK/MAIN BOOM - print on top surface of boom, may need support for the counterbored hole to take bearing, use either plain or flanged 5 ID x 8 OD x 3 bearings or change to suit - 2 bottom layers - 2 top layers - 2 perimeters - 10-20% infill - suits Boom band and 5 OD mast.
There are alignment marks (top and bottom of hull) for mast positions and rudder tube, and cutouts located for fin box and flat deck opening. Cut out the openings.
Fit and glue fin case with fin in place and align with rudder post. Glue joiner into rear half of hull. Fit and glue CF mast tube(or tubes if using swing rig - I use 5mm masts) - check vertical alignment with fin. Note: there are alignment marks in hull for both conventional and swing rigs, on top and bottom of hull. If using a swing rig, you will need to determine requirements for bearings etc. Glue front half of hull onto rear half. Design, fit and glue servo platforms, battery and receiver boxes. Fit a fastening screw (2 mm) into top of fin.. Using the alignment marks, fit and align rudder tube and post, and glue.
Make and fit all the other bits and pieces, make up rigs, and float with weights on deck to determine lead ballast needed to float to bow/stern level and note position of weights. Fill bulb with lead shot, block end of bulb, tape bulb to bottom of fin and float it. Adjust bulb fore/aft to get boat to float at bottom of bow and transom.
I designed the hull using FreeShip (Free!!!), and modified the deck with OpenScad (Free!!!) and Slic3R (also Free!!!). However, I printed it using Simplify3D (alas AU $250). All of the internal components, fin, rudder, booms etc were designed using OpenScad and printed on my Atom 2.0 delta or on my FF Dreamer.
Lesson Plan and Activity
A hull design for the NANO 500 RC class yacht.
Printing filament - I used PLA
Epoxy glue to add the internal components