Loetinator - Electronic Soldering Helper

The "Loetinator" is a helping "third hand" especially to use for soldering. It is a moveable working top with the possibility to attach your (vero)board. You can easily rotate and move the working top (or board) without using your hands - they can stay on your tools the whole time! That means you can easily use both hands for soldering all the time, which means that you safe a lot of time. With a few modifikations you can also use the "Loetinator" to color art projects or something like that.

The project is not even close to perfect yet. But it's working and functional, nevertheless we would love to hear your opinions, improvement suggestions or any form of feedback!

It was developed with support from the RWTH Aachen FabLab in the Multimodal Media Madness course.

Step 1: The Foundation Slab

We start with the foundation of our work. We used a big wooden plattform (24cm X 30cm X 2cm). The size does not matter, but you have to use a plattform that can hold the weight of the whole construction. We thought a blank wooden plattform is kind of boring, so we decided to engrave "LÖTINATOR" at the bottom and cut the front corners round.

The next step is to build the mainpost for the agile construction. We took a wooden board (10cm X 25cm X 1.5cm). The board has to be long enough to gurantee that you can turn the construction in every direction without hitting the ground. The mainpost should also fit the design of the foundation slab, so we also cutted its corners.

Step 2: Mainpost: Mounting the Motor

First, it's time to mount the motor and the axis on the main post. To do that, we drill a hole that has a diameter similar to the axis we want to use. We used a 8mm drill and an 8mm axis. The hole should be positioned around 10-15cm from the bottom of the main post, and in the middle from left to right.

Check if the axis fits through - if not, adjust the hole so you can turn it without much force. Be careful not to make it too big! Now, drill the same hole throught a metal plate, and mount it on top of the hole in the wooden post, so the axis goes through both. Fix the metal on the wood by using screws as shown in the picture.

Now on to the axis. You should find one that is around 3cm long and has an inner screwthread so you can put a smaller screw in it one one side. On the other side, we weld/solder a tiny metal plate (around 3xm x 3cm), drill 4 holes in it and mount the motor adapter on it. This might be a bit difficult, depending on what tools are nearby. It should look somehow like the one in the pictures.

Put the finished axis through the hole you drilled earlier, mount the motor on it and see if you can still turn it without too much imbalances. Then, cut a mounting for the motor (you can use the one in the svg-file here if you have a similar servo) and fix the servo on it using 4 screws. Measure the outer holes of the mounting and drill those into the main pole as well. Then, put the motor with the mounting on the axis, use 4 very long screws going through the main pole to the motor mounting, and use 4 space-holders to fasten the mounting on the main pole, and with that the motor itself, check the picture, it says more than all those words. Test the axis and see if it still turns easily.

To finish this step, just drill another 9-10mm hole on the bottom of the main post to later put the cables from the other servos through. 2cm from the bottom up hould be fine.

servobefestigung.svg
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Step 3: Mainpost: Adding the LEDs

After the motor is fixed on the main post, we add some light! This is not a neccesary step, but it makes the whole thing better looking. We add two things: A light bar with 7 white LEDs to illuminate the working plate and a bar with 3 LEDs and signs to show the current turnable axis.

For the light bar, drill 3 holes medium holes for all the cables through the main post, around 4cm from the top down. Cut a separate bar out of a piece of wood, drill seven 5mm holes for the LEDs and two M3 holes to fasten it on the post. We used a thin sheet metal, bent in the middle so that it forms a spiky angle. Fix one side to the post, one side to the LED bar. Solder 100 Ohm resistors (depends on what LEDs you use!) to the LEDs, and put the cables through the already drilled holes. As always, take a look at the pictures!

For the mode bar, just drill 3 holes for the (green) LEDs and use 4 wood screws to fix it on the pole, just under the LED bar. makes sure to drill the LED holes all the way through the main pole as well, add 200 Ohm resistors (depends on what LEDs you use!) to each of them and if you want, engrave some signs to identify each mode. Pictures show more!

symbols.svg
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Step 4: The U

The next step is a wooden "U"-formed bracket, which has to rotate the working top, a round plate and another plate with two servos attached. Therefore the "U" has to be solid, but also small and not heavy. You only have to cut out the three parts (we used a solid 5mm wood) and put them together (see files : hinten.svg; rechts.svg; links.svg). You need two (metal) brackets and a few screws to build the "U". The smallest wooden piece is in the back, the one with the hole is the right one and the hole has to be on the outer side of the "U".

On the back side, use a screw with a very large head that fits in the previously mentioned inner screwthread of the main axis. Mount the "U" on said axis and fasten the screw as much as possible, without breaking the wood of course. On the right side of the "U", where the 3 holes are shown in the svg picture, you mount one of the Servo adapters and fasten it as well. Cut whatever is bigger than the frame.

Step 5: The Supporting Plate

The supporting plate is one of the key elements of the moving element. We have to attach two Servos on the plate, the 360° Servo and one 180° Servo. Cut the obere_platte2.svg file and 3D-print the servohalterung.stl. The small holes fit with the 3D-parts. It's to mount the 180° Servo to the plate. The holes in the middle are to mount the 360° Servo in the middle off the plate.

The other Servo should be fixed with the 3D-printed part. You have to put the part around the Servo and fix it. The other two holes should fit exactly to the holes on the plate. Mount the Servo, facing to the outside, the rotary axis on the same level as the rotary axis from the 360° Servo. You have to lower all screws on top of the plate, because we will mount a turntable on top of hit. If the screws are not low enough the turntable will not turn in a proper way.

The pictures show this in a more intuitive way!

Step 6: The Turntable

At the top of the board with the servos we need another - this time round - plate, with holes for brackets and a big hole where we attach the 360° Servo (Lasercut: drehplatte.dxf).That's pretty straightforward to create, especially with the pictures.

drehplatte.dxf
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Step 7: Putting It Together

At first mount the Intel Galileo board to the foundation slab. We took the existing holes from the Galileo board and drilled 4 fitting holes in the foundation slab. It's best to add the Galileo at the back of the foundation plate, around 1cm away from it.

Next to the Galileo board we fix the mainpost with 4 large screws. Be sure to fix it very firm and in the middle of the slab, a few centimeters further to the front from the Galileo.

The "LÖTINATOR"-writing should be at the front of the construction, as seen in the pictures.

Step 8: Wiring

The wiring isn't half as complicated as it seems. Use a second power supply unit (5V, 2 Ampere) for the servos, depending on which motors you use. Connect the data cables from the Motors with three PWM ports from the Galileo.

Put the Data wires from the Pedals and the Hand Controler (2x pedals, 3 x hand controller) into the analog pins, avoiding the A0 one, that one seems to influence the others somehow...

Connect the LED switch and the Hand Controller switch with the Galileo as well, then, add the external power supply to the Motors, and connect the ground and 5V cables going to the pedals and Hand Controller with the Galileo. Do the same with all the LEDs.

Step 9: Cable Boxes

Now that the Loetinator is functional, it's time to put some effort into making it more...beautiful.

To do that, we designed two boxes that cover the cables, and used the lasercutter to create them.

The first box, covering the back of the main pole, is a bit tricky to design yourself - just use the svg files to cut them out, and some wood glue to fasten them together. Just stick it between the back motor mounting, it should hold there pretty well.

For the second box that covers the Galileo and all the other cables, you can use the other svg file. On the top plate, cut a 7cm, x 2cm rectangle such that the box fits below the motor mounting. Drill another hole on the side facing the front of the Loetinator and fasten the switch that enables the seven white LEDs into that hole. Use two screws to fix that plate to the main post, and glue the other 4 parts together. Now you can just shift that part on the fixed front side. See pictures for more!

Step 10: Hand Controls

To test and adjust the working plate, we created a little Hand Controller. Turned out it was quite useful, so here you go:

You need an analog Joystick without springs to put it into zero-position, and a linear potentiometer that you can rotate around. Use a flat cable with six wires to connect them to the Intel Galileo: Ground, 5V, 2x Data for the joystick, 1x Data for the Rotator Poti, and 1x Data for the Switch to enable the Hand Controller.

Then, cut a box out and engrave the descriptions on it, as seen in the pictures!