P3, a great model that sails well and stays dry
Print Your Own Radio Controlled Yacht
Following on from the successful balsa Racing Sparrow there is now also the option to 3D print a Racing Sparrow.
Questions? email info@racingsparrow.co.nz
Key design features:
- Hull printed in 4 parts (max size 207mm each)
- Printed rig fittings
- Twist hatch for waterproofing
- Bulb shell in 2 parts, filled with lead shot
- Keel in 2 parts, with carbon reinforcement slots
- Rudder printed as one piece
- Uses standard servos for 2-channel RC
- Minimal build time required
Comprehensive Instruction Manual
The 3D designs has an instruction manual which has sail plan, materials list, electrics list and more. This 3D construction method is a very fast way to make a good model yacht and this manual makes it easy.
3D Printed Hatch and Fittings
The main hatch is a twist on hatch that keeps the water out. No tape failure keeps the sailing relaxed. All rig fittings are printed parts including a tidy gooseneck assembly which is all attached to a carbon tube mast 6mm. The booms are 5mm carbon tube.
Clean Stern Design
Designed to print easily without any extra build steps the stern design integrates a water catch tray, a rudder post, a sheet return block and also a backstay attachment slot. This design makes the rear end of this boat tidy, functional and sleek.
No tape is needed to seal the boat when sailing. We've tested it in stormy conditions as well as calm and the boats are always dry inside at the end. You will be surprised how many features are packed into one 1 STL file.
Simple Clean & Cheap Electrics Layout
The electrics used are some of cheapest servos and RC gear you can buy. No special drum winch required as the Racing Sparrow uses a standard servo with a long arm to pull the sails in and out. This keeps the costs way down. This is a key consideration of all Racing Sparrow designs.
What is the 3D Racing Sparrow all about?
What will I need to finish the 3D printed build?
To finish you need:
Sail Servo Futaba 3003
Rudder Servo Corona 929MG
Receiver Radiomaster R86
On/off switch
Futaba Battery Holder & 4AA
Futaba - Sail Servo Arm
Tiller Arm 3mm hole
Carbon 6mm Mast x 950mm
Carbon 5mm Booms x 500mm
Carbon Rod 3mm, Rudder & Keel
Carbon Bar 6mmx4mmx1m, Keel
Mylar Sail Material 0.5x1m
Sail Repair Tape
Fishing Braid line & Lure Parts
Coated Fishing Wire & Crimps Pack.
800g Lead Shot - Gun Shop
Super Glue
Araldite Epoxy
Resin - Runny for Lead Bulb
Transmitter - Radiomaster Pocket (Authors Favourite)
What 3D printer settings are needed?
Print Settings
- Nozzle: Standard 0.4mm
- Wall Line Count: 2
- Top Layers: 4
- Bottom Layers: 4
- Infill: 100%
- Print Speed: 180mm/s
- Bed Adhesion: Wide brims inside and outside used for hull sections, no glue or sprays required
- Material: eSun PLA+
- Most parts: 220°C nozzle, 65°C plate
- Thinner/smaller parts: 230°C nozzle, 60°C plate
- Enclosure Temperature: ~30°C for best bed adhesion
- Retraction Distance: 0.8mm (reduces stringing)
What Filament is used to print this boat?
One roll of PLA+ will be enough to print the hull bulb, fins and rig fittings.
Is the hull light weight?
Yes the hull weighs around 450g. The combined keel & bulb is 900 - 950g.
How is the keel bulb weighted?
The bulb is a printed shell which you fill with lead shot from a gunshop. It's a very simple and creative way to create a lead bulb. Could not be easier. In New Zealand lead shot can be purchased from this online store.
How are the sails made?
The sails are both one piece mylar film. No sewing or double sided tape needed. You can use many materials such as grow shop mylar reflective film, architectural drafting film or ripstop nylon. What ever you choose simple flat sails work well. No need to build special complex sails. The one piece sails naturally create a nice aerofoil shape with the help of some battens on the trailing edges. Simple!
Do I need to waterproof the hull?
No. I've done many sails now with a Racing Sparrow 3D and I have done no sealing of the printed parts. I simply super glued them together and go sailing.
I sail in sea water and have had no issues. The finish of the hull being printed is not perfect but the boat still sails really fast and a nice finish really is not needed to have a fast boat. Just build quick and get sailing!
Are there any licence restrictions when I buy the STL files?
You can print up to 5 boats with 1 printer when you purchase the STL files. If you want to print and sell boats please get in contact with me to arrange terms.
At Racing Sparrow we are not too concerned with paying a fee per boat print. We would rather the STLs allow people to build multiple boats and get more people sailing and having fun.
The main thing is that no one is making money from the STL files by selling boats, parts or reselling files. If you're not sure please email me first.
All STL files and instructions are copyright 2024 Bryn Heveldt.
Is this the same as the balsa wood Racing Sparrow
Yes the same lines were used. The 3D version is 760mm in length and true to the original Racing Sparrow which sails really well and looks great!
Printed Parts
The majority of the boat is printed including all rig components. This is printed from a spool of eSun PLA+ cold white. The bulb is filled with lead shot, it's a 2 piece component.
You can mix and match colours for different parts of the boat if you like. A white keel and rudder looks great imo, then maybe red hull and bulb with a white hatch cover.
You can even get PLA that is a gradient of colours or even metallics. Get creative!
You could fair the surface and then sand down and spray to get a pro finish or leave natural printed texture for a fast track build. A shiney smoother surface should in theory sail faster. But it would add weight to the hull possibly cancelling out any gains made. It would look awesome and professional.
I have not sealed the PLA+ with resin, it is straight off the printer. Hull joins with CA Superglue, keel araldyte epoxied into the slot. I sail in salt water and find brass rod or plastic is best for the rudder servo control rod. Anything else will corrode quickly. Stainless steel split pins also if sailing in the sea are a good idea.
