Why Bother?
It is hard to explain the feeling one gets when a short time after a design has entered ones head, it is pulling away from you on the wharf. This is what 3d printing has the potential to do for you.
Having fun on the pond with Bill Hagerup’s design, Black Dahlia… fully 3d printed.
This design was emailed to me by Bill from the US as an experimental design. I printed it all up at my home south of Sydney, Australia and within a couple of weeks it was racing around our local club pond.
When was a traditionally built boat done in this time frame from thought to kicking it’s heels with the local fleet?
Experiment, Experiment, Experiment
My background is in the science education area, so the application of the “Scientific Method” to this project came easy and I feel it definitely accelerated the learning curve.
The basic idea of the Scientific Method is to pursue a question or idea one bit at a time keeping all other variables under control as much as possible. With 3d printing it was no problem to adjust one thing at a time and keep the other settings constant.
My ultimate goal was:
“To produce lightweight, smooth, rigid and fast hulls that would be comparable to carbon in strength and mass”
A big ask, yes! Considering a search of the net gave very few hints on how to do it.
The story is a good one. The research has developed beautifully strong hulls down to 0.35mm thickness and easily as good as carbon or glass fibre.
Bill Hagerup RG 65 design: “The Shrink”. I recently finished this beauty, a lightweight flyer. All 3d printed down to the bulb, keel and rudder.
Then there is this sensational new design called “The Nano 500”. More on the introduction to this elsewhere on the site. I am seriously excited about this new class.
I know a large number of RC sailors will take some time to believe this, but the world is changing.
It is the acceptance of something so foreign that is the problem, not the technology. I have been sailing these beauties for nearly 12 months now and moved through many different prototypes in the big experiment. Try doing this with conventional building techniques?
In less than 12 months most of these designs have been thought up, digitally drawn, built and sailed as part of the big experiment. Yes it has been a serious project with a serious agenda all driven by the belief the Radio Controlled Yacht community will be the big winner here.
Following shows a taste of the scope of the testing. No stone was left unturned to get the results that was wanted.
Surface finish. A major desire was to save the aging elbows of our fellow sportsmen from being worn out by constant sanding. An excellent finish is now consistently achieved.
2. Strength with flexibility. These show how truely amazing the 3d printed materials can become.
3. Hull thickness and resilience. This was the tricky one, getting all the variables possible on a 3d printer to line up and produce lightweight and strong hulls. I think we over achieved here with over 300 tests and continuing.
Processes that could be varied and were subject to much scrutiny included: air temperature, nozzle temperature, flow rate of the plastic, speed of the head, layer thickness, bed temperature, material and its colour.
Disasters Are Inevitable.
Yep, and we have had our full share. I would like to show you some of the tear jerking and frustrating things that would pop up out of the blue without warning and without explanation.
Overflow of plastic supply
A computer error producing a repeating ridge
Blocked extrusion nozzle
Ran out of plastic on the roll (silly hey)
Temperature too low
Blocked nozzle again
Misbehaving whilst left alone one afternoon. Should have been a keel box.
Layer adhesion issues, probably temperature related
Probably a low voltage session in the local grid
Long deep lines, showing moving parts when printing. Need to keep things tight.
Another birds nest from a misbehaving printer whilst not watched.
But in spite of the heartache at times, it is all forgotten when your beautiful creation is cruising along at maximum hull speed on a lovely pond on a great day with some mates.
