When I visited the European Space Center earlier this year I picked this cool bubblegram of the planets in our solar system. I decided to make a base for it so I could light it up with some LED’s.
I decided to get with RGB LED’s so that I could have the colour change over time. Making a circuit for one of these was easy enough. I used 3 x 220 ohm resistors for each of the three anodes on each LED.
I soldered the resistors to the LED and added cables for the anodes and cathode.
An Uno board was used to test the LED. pins 9-11 (PWM pins) were used to control the colours and brightness. By altering the PWM width for each colour the brightness of each colour and thus colour mixing can be controlled.
Next I set about designing the 3D model of my stand. I created a block the size of the bubblegrams I have and added a rim round the outside to hold it in place. I hollowed out the middle to make room for the electronics and cut a hold in the side for the power plug.
There is no way an Uno board would fit in the stand so I picked up a Nano to use instead.
Before squeezing the electronics into the case I decided to wrap the RGB boards I had made in shrink wrap to prevent them shorting out if press against the other boards. A hole was cut for the LED to poke through.
The electronics were crammed into the stand. They literally just fit!
The LEDS were programmed to cycle through different colours in a loop.
As seen in my last post there were a few issues with my open RC build that needed resolving. The first was the front wheel axle snapping. I have since printed a whole collection of front axles with 100 % infill (solid). This makes them much stronger than when they were only 20%. As I printed a whole bunch I have spares at the ready if I need them.
The next thing to look at was the steering. Here I was having issues with the servo not centering the wheels with no input. This indicated there were binding issues but it seems the servo may have also been at fault. While playing with the trim settings on the transmitter the servo went crazy and melted itself. There was a lot of smoke coming out so I quickly ripped out the Lipo battery and took the car outside. The house stunk of burnt electronics.
The offending item was removed and remarkably caused no warping to the PLA chassis.
I fitted a new servo and adjusted how the servo linkage worked to make the wire straighter.
I also used a multitool to sand down the inside of the car body so that the servo rod no longer snagged on it. Lastly I added a washer between the servo saver and lower chassis.
These things combined have fixed the steering issues I was having. The steering now centers itself and responds a lot better than before.
I have been having a lot of fun printing TPU tyres at different settings and have made some progress with regards to producing tyres with more grip.
That said the TPU tyres always lacked the grip of a rubber tyre so I caved in and brought some Tamiya tyres. I will go back to TPU when making a heavy vehicle as part of the problem is that the f1 car is so light the tyres are not creating much friction with the ground.
The Tamiya tyres. I had no idea that these came in different compounds so I ended up with super soft rear tyres and standard front ones.
New rims had to be printed for the Tamiya tyres and the wheel ends up a bit bigger than the printed tyre version. You can see that the rear tyre almost touches the bargeboard. This is good as it increases ground clearance a little which should lead to less damage when driving over uneven terrain.
I have only tested the Tamiya tyres indoors at the moment on wooden floor but I can already tell they perform miles better than the TPU tyres. I did make a second video however of my second generation TPU tyres at the weekend. These were a step up from my previous attempt which were much too hard. These are printed at 10%. I still have not had much success with printing them at 5% at all.
Next time with the rubber tyres the lack of grip should be a thing of the past!
So above is a video of my printed F1 cars first outing. For the most part it works pretty well but there are a few teething issues to sort out.
First the tires I have printed have no grip. I printed them with far too much infill and they are no where near soft enough. I do not want to give up and go to Tamiya tyres so will be playing around with reducing the infill and making these softer.
Secondly as you can see in the video the front axle snapped, I have reprinted a whole tray of these solid so the next ones will be stronger and if not I now have spares.
Lastly its not very noticeable in the video but my servo pusher is rubbing up against the body shell and causing the steering not to return to center. This should be easy to fix but I need to unscrew the body first.
So the rest of my open RC F1 car is printed and it was time to get onto the most tricky part the tyres. The rest of the car was printed in PLA but the Tyres need to be flexible so they are printed in TPU.
The TPU brand I purchased was Enotepad. It arrived in a box that looked plain apart from a logo that reminded me of good old word art. The filament felt flexible to touch so it was a good sign it was not PLA.
You can find my print settings at the end of the post.
I recently built a new 3D printer having wanted a bigger build bed and to go back to open printing. I went for the Ender 3 Pro which has turned out to be a great machine for the price.
I have always wanted to print and build an Open RC car but did not have a big enough print bed to print the parts. Now I do however so I thought it would make a good test for my new printer. All of this model apart from the Tyres will be printed in PLA. The Tyres will be printed in TPU so that they are flexible.
The first thing I did was to try printing the chassis. I printed this with a bit more infill than the rest of the parts to make it stronger. The chassis parts and the rear axle holders were printed at 35% infill. Continue reading Open RC F1 Car Part 1
I printed this cool little paddle boat over the weekend. It was simple to print and just needs an elastic band to power it.
The model was made by user swtchrwr on Thingiverse.
Click here for a link to the model and the settings I used to print it. I printed the hull at 5% infill to make it nice and light.
Because the boat at full scale was too big for my printer I printed it at 60%. The pegs and paddle were too big for the hull so I printed the paddle at 50% and the pegs at 60% with a few mm taken off the width and depth.
Hopefully I will be looking at printing a steam powered boat next.
I have been so busy playing with my 3D printer that I have neglected posting about it. I find it to be a deceptively simple machine with much configuration required to get things going smoothly.
I have got to the stage now where I can look at a 3d model and make the required tweaks to suite the printing of that particular model. This helps to avoid wasting time and filament on prints that are doomed to fail and is particularly important when you consider printing can take many hours.
Here is one of my favourite prints so far. Bender from Futurama painted using Tamiya paints. I downloaded model for this print from thingiverse details are underneath the images