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This is my digitally fabricated auger based pet food dispenser.  You simply load the pitcher with pet food and it is automatically pushed with the auger screw into the dish to feed your pet.  This has been tested to work with cat food and designed with a cat in mind.  Actually this is going to be a Christmas present for my sisters cat.  

In the past year I have been working to up my game when it comes to fabricating parts for my projects.  If you were to check out some of my older Instructables you would see most things I made were built with three basic tools, a drill, a saw of some sort and a dremel.  These tools serve me well but I had to limit my material choices and construction techniques to match the tools.  I was always designing parts around these limits and trying to source pre-made parts whenever possible.  I had some success with this but always thought it would be nice if I could make cuts a little straighter and make things with more complex geometry.

So during the end of 2011, I started working on a cnc router.  I finished it in Febuary 2012 and posted all the plans for it here on Instructables  DIY CNC Router  It has been an awesome tool and I have used it many times.  I've made things for my aunt, my sister, my cousin's eagle scout project and a fishing poll rack for my Dad.  Around the same time I was finishing up the router, MakerBot released the Replicator and I got caught up in all the hype of 3d printing.  I poured myself into this new subculture I found on the internet and I when I emerged from my fasination with these cnc hot glue guns I decided to buy my own 3d printer.  There are many DIY level 3d printers available but the one I decided to get was an M2 from MakerGear.   It is my opinion that this printer has the highest quality components and uses the best manufacturing techniques of any DIY level 3d printer currently available.

So now that I have a CNC router and a 3d printer I decided to work on a project specifically geared toward using these tools to take advantage of their capabilities.  The pet feeder is that project and in this instructable I will to explain how I used the machines to create some unique parts.

This design for an auger screw based kibble dispenser was inspired by Tunell and kitlaan of Thingiverse but I created all of my own 3d models for this design.  I have uploaded the design files to Thingiverse as well Pet Feeder Thingiverse #34100  
            

Step 1: Materials and Tools

The parts needed for the pet feeder are easy and cheap

  1. 2" PVC Plumbing Tee
  2. Dollar store drink pitcher
  3. PLA plastic filament for 3d printing (ABS could also be used)
  4. 3/4" Oak Hardwood board (any sheet material could be used, 1/4" Acrylic could replace this)
  5. 4-40 machine screws, nuts and washers
  6. Continuous Rotation Standard Hobby Servo (I used a Parallax servo)
  7. Exacto Knife (for cleaning up the prints)
  8. Drill
  9. 3d printer
  10. CNC router (or laser cutter)

Step 2: 3D Printed Parts

I designed the pet feeder to have most of the parts 3d printed because I wanted to explore the possibilities of mechanical design with 3d printing.  These parts are integrated with off the shelf parts and assembled with the machine screws.  I designed the parts to have slots and hex shaped holes to capture nuts so the parts could be assembled with minimal tools.  The ability to integrate the nuts and bolts into the design of the parts is somewhat unique to 3d printing and makes for clean looking and purpose built items.  I really like this aspect of 3d printed design.

The general software tool chain used to create 3d printed parts is like this: design a 3d model on the computer, slice the model into layers and write G-code which is used by the printer, send the G-code to the printer as the parts is being made.  This requires 3 different pieces of software(design, slice, send).  I did all the design work for the pet feeder using Solidworks.  This is a really great 3d modeling software but is very expensive.  I will not always access to this software so I have been looking into the cheaper/free options.  Autodesk 123D, OpenSCAD, FreeCAD are three programs I have been considering.  After I designed the parts I exported them from Solidworks in the .stl format.  The stl format is basically a list of numbers that define the points of many triangles in 3d space.  The triangles are placed so that they match the outside surface of the part designed in the 3d modeling software.  Now that I have the .stl file it can be brought into the slicer program.  I used Slic3r but some other options are Skeinforge and Kisslicer.  In the Slic3r program I input the parameters of the M2 printer, the filament I am using, and the settings that control how the part will be made.  Slic3r takes that information and cuts the model into thin slices.  The shape of each slice is then used to create the G-code needed to run the printer.  The output of Slic3r is a text file but is normally given an extension .GCODE.  The G-code is a list of instructions that tell the printer to move from one position to the next while also turning the extruder motor to force plastic out of the nozzle and onto the previous layer of plastic.  This list of instructions can be very long, tens or hundreds of thousands of lines long, but don’t worry because you’ll probably never have to go though them.  You may sometimes need to edit the few lines at the beginning and end of the file but its not a big deal.  I then loaded the G-code file into Ponterface which is the program that sends the G-code to the printer.  Ponterface is also used to manually control the printer’s movement and temperatures.  Once the G-code is imported and the extruder is hot you can hit the print button and the printer will begin to make the part.

These are the general Slic3r settings I used to make the parts.  These settings make structurally sound parts needed for the pet feeder.  I used Slic3r version 0.9.3.

Layer Height=0.2mm
Perimeters=2
Solid Layers=3
Infill is rectilinear with 0.2 density every layer at 45deg
Perimeter Speed=90mm/s
Infill Speed=100mm/s
Bridge Speed=100mm/s
Travel Speed=200mm/s
2 Loops for the skirt

The parts needed for the pet feeder are listed below with quantities and actual print times based on the settings already mentioned:
  1. Pitcher Funnel - Size 97x97x58mm - QTY 1 - Print Time: 2hr 57min
  2. Servo Mount - Size 67x93x26mm - QTY 1 - Print Time: 1hr 16min
  3. Wood Support - Size 79x32x32mm - QTY 2 (printed at the same time) - Print Time 1hr 15min
  4. Auger Screw Cut 1 - Size 59x124x30mm - QTY 1 - Print Time: 1hr 11min
  5. Auger Screw Cut 2 -Size 59x124x30mm - QTY 1 - Print Time: 1hr 11min
  6. Kibble Dish - Size 108x97x23mm - QTY 1 - Print Time: 1hr 32min
Add that up and you get 9hr 22min of print time! I like to design my entire project before I even make the first part because I often make good revisions while going through the design process.  After I finished printing all the parts I realized that 3d printing is boring and awesome at the same time.  I was able to do other things while the printer was running but I missed out on the enjoyment of actually making something.  My profile reads "I enjoy making things more than actually using them" and 3d printing has challenged this.  Its awesome seeing something you've imagined and created on a computer just come to life but it feels like something is lost from just clicking buttons to make it happen.  Hopefully I can find a balance for projects in the future.      

I've included the stl files for your printing enjoyment.  All should be scaled and orientated correctly, let me know if there are any issues.  If you would like to view the files easily download NetFab Studio Basic which a great program to view and prep stl files for 3d printing. 

Step 3: CNC Parts

There are two identical parts for the pet feeder that I cut on my CNC router.  They are made to fit around the PVC Tee and and act as stands for the whole device.  I made the parts from 3/4" oak hardwood because I had a piece of this left over from a previous project.  Any sheet material could be used and I think 1/4" acrylic or wood could work fine, you could cut this on a laser cutter.  I have provided the .dxf file(scaled in inches) for easy fabrication and modification.  

Just like in 3d printing there are 3 basic software packages used to create a part.  You must first design the part, write the G-code and then send it to the cnc machine.  Like the 3d printed parts I designed the cnc parts in Solidworks and then exported them in .dxf format. This is a widely accepted format used to exchange 2d drawings.  This format is often used to write G-code using a CAM program(CAM=Computer Aided Manufacturing).  The CAM software I used to write the G-code for these parts is CAMBAM    When cutting wood or any material with a cnc router there are many different software settings that go into creating the G-code.  Just like with all the settings available in the slicing programs for 3d printing there are just as many, if not more, settings available in CAM programs that are used to write G-code for cnc machines.  Basically you import your dxf file, which is a 2d drawing of the shape you want to cut.  You select the shape, choose the diameter of the bit you will be using and decide how the part will be cut.   With cnc machining you have to know how much material you can take off in one pass.  In 3d printing you decide how thick each layer is and with cnc you decide how deep the router bit will cut on each pass.  Layer Height is to 3d printing as Pass is to cnc machining.  Layer height adds material and Pass subtracts material.  Generally a pass with a CNC machine has a depth of cut and a percent overlap, which is how wide the cut will be compared to the width of the bit.  CNC machining has been around much longer than 3d printing and many standards have been written for deciding how to cut material.  Making this is decision is often referred to as figuring out speeds and feeds.  Speeds and feeds calculator programs are avaiable and one good one is G-Wizard from CNC Cookbook.  You input your bit size and type, material, pass depth and the power of your router and the program tells you how fast the router should be spinning and how fast it should move through the material.  This is for the ideal cutting situation and can often be tweaked for the best results.  If your settings are to far off the limits of your machine you can easily break bits or stall the router and stepper motors.  This is not a good thing and cnc machines are much less forgiving than 3d printers in this regard.  Once the G-code is finished I used Mach3 to control the router and send the G-code.  This software is widely used by people with home built cnc machines.  

 Here are the basic settings I used when cutting the two parts:

Cutting Bit: 1/4" diameter 2-flute down spiral router bit
Depth of cut: 0.100"
Cut feed rate: 40 in/min
Plunge feed rate: 10 in/min     
Rapid speed: 200 in/min        

If you decide to use a thicker material and cut it with a router, like I did, I want to give you a tip.  I cut the two parts together which saves time and makes sense.   I spaced them out to give just enough clearance for the 1/4" bit I was using to make the cut.  This was not a good decision,  I should have spaced them out even more.  The first part went just as planned and the router was cutting the second part out just as well.  On the final pass the entire board broke loose, sending the first part flying and the second part got jammed into the router bit.  This stalled the router and the stepper motors.  I hit the e-stop once I realized what had happened but it was stalled for at least a second or two.  The part was not completely ruined so I finished it with my dremel.          

Step 4: Assembly and Operation

To assemble the pet feeder you'll first need to clean up the printed parts.  Scrape off any loose filament and drill out the holes with a 1/8" drill bit.  Insert the nuts into the funnel and the wood support 3d printed parts.  The screws used for everything are 4-40 size with 1/4" nuts.  I used 1/2" long screws to attach everything but the wood stands for which I used longer 1-3/8" screws.  I drilled out the holes on the stands by hand because I don't have a drill bit that will fit in the router.  The wood supports and the funnel attach to the PVC tee by drilling and tapping the tee itself.  Use the printed parts as a guide to position the holes correctly.  Make sure the ends of the screws don't protrude into the PVC tee.  The auger screw connects to a standard X -shaped servo horn and already has the holes designed into the part.  Use screws and nuts to attach the screw to the horn while it is attache to the servo.  Then bolt the servo to the servo mount.  Just use the top two holes to mount the servo.      

I am still working on the operation of the feeder.  Right now I know that in order to drive the auger screw and not get kibble jammed, the screw must be reversed to free up the kibble.  I am using a basic stamp to drive the servo and through testing have determined a sequence of moves for the screw to avoid jams.  The sequence is first a 60 degree turn backward then 120 degrees forward and repeat.  This has not jammed yet and can be repeated as many times as needed to dispense the desired amount of kibble.  There are so many options for controlling the feeder that I have not made the final decision about I how i want to do this.  I also might include a button that the pet could press to dispense food, don't know if this would work.
<p>Last update, I have added a second mini servo to open and close an auger door. Cats keep picking out food all day long. Door actions is to allow it to close without getting caught up on food stacked up at the edge. </p><p><iframe allowfullscreen="" frameborder="0" height="281" src="//www.youtube.com/embed/HPRL-vlAiu8" width="500"></iframe></p><p>One other addition was to modify the timer so I could switch the digital display off as it was drawing too much current for the solar charger to keep up if we had a couple days of cloudy weather.</p>
<p>I was looking for inspiration to something similar and when i saw this original build i thought &quot;That could be improved!&quot; but then i saw your post and i was like &quot;that is improved!&quot; i am properly gonna do something like yours with the extra door to keep the cat out and possible make it more or less air tight so the food don't get's to dry.<br>I can only say to your comment about 3D printer. GET ONE! since i got mine i have been able to make automatic greenhouse controllers, candlelight powered phone charger and many other things! :) and don't forget cheep gift for younger parts of the family ;)</p>
<p>Just wanted to say great work on the pet feeder, you've taken it to a new level! You're build looks great.</p>
Thanks, I actually just added yet another option yesterday with the addition of a toggle switch to select more = 1 cup or less = 1/2 cup of food. very simple with the arduino as the controller. <br>Hope to get me a 3D printer next year some time.. just not sure if I have the time to learn the software.. I keep finding things where I say.. If I had 3D printer I could fix that! ;-)<br>Doug
<p>Hi there, i made it with few improvements. I used a stepper motor nema 17, a rtc3231, a lcd16x2 i2c and a blutooth to manage everithing trough an arduino. Take a look here https://twitter.com/the_menda14/status/784251791361867776</p>
<p>And a little antijamming plastic flippers, and two current converters (one ac-dc12v for the stepper and a dc-dc5v for the arduino), and a fuse protected plug</p>
<p>Still working on the finished product but have the controls done. Will be timer based and on-demand.</p><p>Here is a real short video of the timer triggering and unit running</p><p><iframe allowfullscreen="" frameborder="0" height="281" src="//www.youtube.com/embed/exsSEIZ0okA" width="500"></iframe></p><p>The Arduino code and be change very simply to output more or less food, this is the amount for my 3 cats at bed time. I foresee the need for a flapper door at the end of the auger as the cats will be pawing out the food.</p><p>Will outline the electronics and code when finished.</p>
Code arduino??? Please
<p>I have since added an additional switch to allow for 2 feeding amounts as I have started using this at 2x a day and it was too much food. The code reflects this change. Not sure how it will paste into this comment </p><p>Keep in mind, my arduino is only powered on for a few more seconds than it takes to run the code since it is controlled by an external timer.</p><p>Good luck</p><p>// This sketch will operate a servo in the auto cat feeder as soon as it boots.</p><p>// The Arduino is powered on and off with an external timer and relay</p><p>// this was done to save battery power, the Arduino, External 5v regulator, and servo power </p><p>// are all provided 12v when the timer goes off and closes the relay. The boot and ontime of the servo</p><p>// is approximately 13 seconds, the timer on time is about 15 seconds. A momentary push button can be</p><p>// depressed and held to provide voltage for an demand run.</p><p>// Updated 8-14-2016 Feeder now runs 2x day so reducing output changing for loop from a count of 18 to 10 which is 1/2 cup</p><p>// Next update will be to install a switch, set a pin to pinMode(#, INPUT_PULLUP) then when gounded (switch closed) pin is low so set value for loop.</p><p>#include &lt;Servo.h&gt; // include the servo lib</p><p>Servo my_servo; // define my server object</p><p>Servo door_servo;</p><p>int ledPin = 13; // LED connected to digital pin 13 can remove before going live</p><p>int input_value = 1; // when power up set value</p><p>int pos = 0; // variable to store the servo position</p><p>int check_pin = 0; // temp var to read pin value</p><p>int loop_cnt = 0; // var to hold max number of loops (for loop)</p><p>int lessfood = 0; // pin 0 will be input_pullup so when it goes low less food</p><p>int morefood = 2; // pin 2 will be input_pullup so when it goes low more food</p><p>void setup()</p><p>{</p><p> pinMode(ledPin, OUTPUT); // sets the digital pin as output so I know it is working with no servo</p><p> my_servo.attach(9); //Attach pwm signal wire to pin 9</p><p> door_servo.attach(8); //Attach pwm signal wire to pin 8 for door servo</p><p> pinMode(lessfood, INPUT_PULLUP); // Switch to gound for less food (1/2 cup = 10 iterations)</p><p> pinMode(morefood, INPUT_PULLUP); // Switch to gound for less food (1/2 cup = 10 iterations)</p><p>}</p><p>void loop()</p><p>{</p><p> // soon as powered up run </p><p> check_pin = digitalRead(lessfood);</p><p> if (check_pin == HIGH){</p><p> loop_cnt = 10;</p><p> check_pin = LOW;</p><p> check_pin = digitalRead(morefood);</p><p> if (check_pin == HIGH){</p><p> loop_cnt = 18;</p><p> check_pin = LOW;</p><p> }</p><p> if (input_value &gt; 0) { // Open door in front of auger</p><p> door_servo.write(20);</p><p> for (int cnt = 0; cnt &lt; loop_cnt; cnt++) {</p><p> if (input_value &gt; 0 ) {</p><p> digitalWrite(ledPin, input_value);</p><p> my_servo.writeMicroseconds(1425); // Backup</p><p> delay(250);</p><p> my_servo.writeMicroseconds(1600); // Forward</p><p> delay(350);</p><p> } // end if</p><p> } // end for </p><p> digitalWrite(ledPin, 0); // Turn off LED</p><p> my_servo.writeMicroseconds(1425); // Backup</p><p> delay(250);</p><p> my_servo.writeMicroseconds(1500); // stop servo</p><p> delay(500);</p><p> door_servo.write(90);</p><p> delay(500);</p><p> door_servo.write(20);</p><p> delay(500);</p><p> door_servo.write(90);</p><p> delay(500);</p><p> door_servo.write(20);</p><p> delay(500);</p><p> door_servo.write(90);</p><p> delay(500);</p><p> door_servo.write(20);</p><p> delay(500);</p><p> door_servo.write(90);</p><p> delay(500);</p><p> }</p><p> input_value = 0; // All done so set value so nothing happens in the next loop.</p><p>} // End void loop()</p>
<p>thank <a href="https://www.instructables.com/member/airscapes" rel="nofollow">airscapes</a>. but I need a simple code to my servo feeder can feed without others. help me!!!!!!!</p>
<p>This is the simplest version I have. </p><p>// This sketch will operate a servo in the auto cat feeder as soon as it boots.</p><p>// The Arduino is powered on and off with an external timer and relay</p><p>// this was done to save battery power, the Arduino, External 5v regulator, and servo power </p><p>// are all provided 12v when the timer goes off and closes the relay. The boot and ontime of the servo</p><p>// is approximately 13 seconds, the timer on time is about 15 seconds. A momentary push button can be</p><p>// depressed and held to provide voltage for an demand run.</p><p>// Updated 8-14-2016 Feeder now runs 2x day so reducing output changing for loop from a count of 18 to 10 which is 1/2 cup</p><p>// Next update will be to install a switch, set a pin to pinMode(#, INPUT_PULLUP) then when gounded (switch closed) pin is low so set value for loop.</p><p>#include &lt;Servo.h&gt; // include the servo lib</p><p>Servo my_servo; // define my server object</p><p>Servo door_servo;</p><p>int ledPin = 13; // LED connected to digital pin 13 can remove before going live</p><p>int input_value = 1; // when power up set value</p><p>int pos = 0; // variable to store the servo position</p><p>int check_pin = 0; // temp var to read pin value</p><p>int loop_cnt = 0; // var to hold max number of loops (for loop)</p><p>int lessfood = 0; // pin 0 will be input_pullup so when it goes low less food</p><p>int morefood = 2; // pin 2 will be input_pullup so when it goes low more food</p><p>void setup()</p><p>{</p><p> pinMode(ledPin, OUTPUT); // sets the digital pin as output so I know it is working with no servo</p><p> my_servo.attach(9); //Attach pwm signal wire to pin 9</p><p> door_servo.attach(8); //Attach pwm signal wire to pin 8 for door servo</p><p> pinMode(lessfood, INPUT_PULLUP); // Switch to gound for less food (1/2 cup = 10 iterations)</p><p> pinMode(morefood, INPUT_PULLUP); // Switch to gound for less food (1/2 cup = 10 iterations)</p><p>}</p><p>void loop()</p><p>{</p><p> // soon as powered up run </p><p> check_pin = digitalRead(lessfood);</p><p> if (check_pin == HIGH){</p><p> loop_cnt = 10;</p><p> check_pin = LOW;</p><p> check_pin = digitalRead(morefood);</p><p> if (check_pin == HIGH){</p><p> loop_cnt = 18;</p><p> check_pin = LOW;</p><p> }</p><p> if (input_value &gt; 0) { // Open door in front of auger</p><p> door_servo.write(20);</p><p> for (int cnt = 0; cnt &lt; loop_cnt; cnt++) {</p><p> if (input_value &gt; 0 ) {</p><p> digitalWrite(ledPin, input_value);</p><p> my_servo.writeMicroseconds(1425); // Backup</p><p> delay(250);</p><p> my_servo.writeMicroseconds(1600); // Forward</p><p> delay(350);</p><p> } // end if</p><p> } // end for </p><p> digitalWrite(ledPin, 0); // Turn off LED</p><p> my_servo.writeMicroseconds(1425); // Backup</p><p> delay(250);</p><p> my_servo.writeMicroseconds(1500); // stop servo</p><p> delay(500);</p><p> door_servo.write(90);</p><p> delay(500);</p><p> door_servo.write(20);</p><p> delay(500);</p><p> door_servo.write(90);</p><p> delay(500);</p><p> door_servo.write(20);</p><p> delay(500);</p><p> door_servo.write(90);</p><p> delay(500);</p><p> door_servo.write(20);</p><p> delay(500);</p><p> door_servo.write(90);</p><p> delay(500);</p><p> }</p><p> input_value = 0; // All done so set value so nothing happens in the next loop.</p><p>} // End void loop() </p>
<p>thank you!!!! I tried but my servo spin forever. I do not know there is a problem with your servo</p>
dear airscapes!!!!Helppppp!!!! My servo rotation is not like yours. I don't know why???
<p>Not sure I can help, I used the exact same model the as the original instructions say to use. Code makes it move forward and back. You must zero your servo with a little program found in the library, you run that program and turn the screw ever so slowly till it stops moving. Then reload the code you want to run.. may be the problem.. not an expert learned what I needed as I did the project using google.. </p>
Thank airscapes. I use servo mg 995 hacked, i dont know it active isn't
<p>I finally finished this project. The controls consist of a Timer which when triggered send 12v to a voltage regulator for about 20 seconds. This feeds the Metro mini and the servo. The mini runs the servo code and stops when complete, the timer shuts off power about 5 seconds later. I am running this with a 5A 12v battery which will be tucked away out of sight. It is kept charged with a 2 Watt Solar battery maintainer. </p><p>I added a small slice of pipe to the inside of the Tee to fix a small design flaw. The opening in the servo housing that lets you slide it over the motor also let small kibbles behind the auger flange in the servo horn chamber. This can cause a jam. Once the slice of 2&quot; pipe is glued in place, the auger must be screwed in to the tee. </p><p>The electronics enclosure was made by hand, unfortunate no laser cutter at hand.. </p>
<p>Finished up the assembly but may new stands out of hardwood and change the shape possible to allow the boards and battery encloses to be mounted. I altered th lower part of the stand so it would HOLD our stainless steel cat plates in place. Next the electronics and encloses.. sure wish I had a 3D printer.. </p>
<p>I have cleaned up my auger using 180 grit sand paper taped to a slab of granite. Sanding the mating surfaces this way produced a perfect fit allowing me to use a plastic weld product (methylene chloride) to weld the pieces together. Just hold them together where you want them and lightly coat the seams and it just sucks, hold tight for about 15 seconds. I then used a hair dryer to heat the tips of the auger blades to line them up. Next filled the gap with Locktite Marine epoxy which does not really bond well to plastic but is more or less just used as filler. The TEE was bored out with a vertical drum sander similar to this <a href="http://www.woodcraft.com/product/157889/woodriver-benchtop-spindle-sander.aspx" rel="nofollow">http://www.woodcraft.com/product/157889/woodriver-...</a></p><p>Then hand sanded with 320, 800, &amp; 1000 grit wet for a perfect fit without altering the auger.</p>
<p>Please note the auger was made with the suggested PLA plastic and super glue (cyanoacrylate) is said not to work well. This is why I used the methylene chloride. </p>
<p>I have found a way to allow all 4 servo attachment screws to be used. Before attaching the auger to the server and with the horn removed, install the servo in the back cover and center the bottom servo holes and cover holes. Now put a nut halfway on one of you longer 4-40 screws. Using a lighted magnifier glass if you are old like me, apply a small amount of Locktite gel super glue to the back of the serve ears where the nut will rest and then drop in the screw shaft and nut. Hold for 20-40 seconds and unscrew the screw. You can now assemble everything and use 4 screws to attach the server, just don't crank down the bottom screws as the glue is not that strong.. Don't forget to drill out the end horn holes to accept a 4-40 screw. Use a 1/8&quot; bit and a drill press if you one, and hang on to the server. </p><p>(1/8) bit. Use a drill press if you have one and hang on to the server.</p>
<p>Ok, figured that out. There are 2 kinds of PVC schedule 40 Tees, a Sanitary Tee and a Regular Tee. The regular Tee has much less plastic inside that will need to be removed with the drum sander.</p>
<p>I am a bit freaked out.. had the parts printed and the auger is not 2&quot; but 2 5/16. Is this how bit it is supposed to be??? </p>
<p>Ordered the same servo, holes in the horn are very small maybe 1/6&quot; in dia. Holes in the auger are at lest 1/8 or 3/16&quot; What sized and type screw was used to attache the auger and the servo? </p>
<p>Been a while since anyone posted here. I stumbled upon this looking for designs that would let me feed the cats a small amount of food on a schedule. I dove in knowing I could buy an auto feeder for a lots less than I could make one like this but where is the fun in that. Hope it works cause I am committed now. Had someone print the parts, all but the bowl ($40) 10 program timer $30shipped, Arduino $30shipped, Servo $22shipped, voltage regulator (timer needs 12v rest 5v) $5, enclosure?? 12v lithium-ion battery $40, low battery warning module $5 and I am sure I will find more stuff to buy.. ;-) Original idea was 3 one timer and controller, one for each cat as they currently each get their own bowl.. Looking like $70 for each additional unit for printed parts and motor. Will post my end result. </p>
Thanks for this beautiful idea.. I took the tube of a whisky bottle for the food container. Also it wasn't easy to find the us 2 inch t-plumping piece here in Europe. My cat is a bit sceptical, let's see what happens when he gets hungry! :)
<p>I am planning to build an HTTP server from which I can trigger a feed so I will post an own instructable about all the Software parts I needed for realizing your idea. I will link it here as soon as its ready. Thanks again!</p>
<p>Thank you for this nice Instructable. I like it</p><p>Rima</p>
I am in the assembly phase and immediately ran into two problems. First, I set the CNC router to cut the holes in the wood on the inside of the line. When, I tried to put the PVC into the holes, I discovered that the PVC was slightly bigger than the hole. So, I had to use a Dremel sanding bit to make the holes a wee bit bigger. Should I have made the cut on the line instead of inside of it? <br> <br>Second, the augur is almost exactly 2&quot; in diameter. It fits into the first few inches of the PVC, but then stops when it hits the raised part that is meant to stop other PVC piping from going all the way through the T. I noticed in your pictures that your PVC also has that raised part. How did you get around this issue? Print the augur smaller? File the inside of the T to remove the raised part? File down the outside of the augur to fit? <br> <br>Thanks for the help.
Yeah, I had to do some fitting of all the pieces. I sized all the parts to fit the exact PVC Tee I had but yours is probably different. The manufactures of the T's don't make the exact same T even though it has the same use. I had to sand down the outside of the auger to get mine to fit well. You did right by cutting to the inside of the circle on the dxf, hopefully only a small amount of sanding was needed. <br> <br>When your done be sure to post some pictures!
I'm really glad you replied. I was worried I did something wrong.<br><br>Making the hole in the wood was easy. The auger is a bit more challenging.<br><br>I'll definitely post pictures when the whole thing is done. In the meantime, here is a link to the progress posts on my blog: http://beckermaker.blogspot.com/search/label/Pet%20Food%20Dispenser
Why not old mincer without knifes feeded through timer?
Did you ever find how how to control your servo. If so, are you going to expand you instructable?
Controlling the servo is easy with microcontroller such as an Arduino or Basic Stamp. I have already done this and it works well. The question is deciding how and why the food will be dispensed, a simple timer, a button, an app? I've left that up to you, I've provided the functional feeder it&rsquo;s up to you to decide how to use it. <br> <br>I'm actually thinking I may change the whole design of the feeder to be more 3d printer friendly and incorporate a very simple set of electronics for control. Don&rsquo;t know when I&rsquo;ll do it though. <br>
WOW I'M IMPRESSED <br>Keep me posed would like to buy one from you <br>Steve
Can you tell me the printed length of the auger, I have a portabee, it's a little limited on print bed dimensions.
The auger is 124mm long overall. I'll add dimensions to the descriptions so people know if they can make the parts on their printer or not. Also, if you download netfab studio basic you can easily measure and get size and volume specs on any stl file <br>
Thanks for the tip - still new to 3d printing (am still calibrating and modding) <br> <br>I'll have to find a way to knock 5mm off or print it diagonally... <br> <br>(side note, this comment system is arse, the captcha doesn't work properly when you hit the reply button...)
Greetings, The cat'll go loopey trying to dig to the fresh food - which cats of all sizes much prefer. Yup.
Your right cats are picky about the freshness which is why I haven't decided the best way to control the feeder. I don't think a timer is the best solution and coming up with something better is going to take some effort. Any suggestions?
a little outside of the box, but if you don't want to use a timer you could make an app on your phone that could schedule and/or have a feed button and alert you when the food is low. similar but alternative would be a console mounted somewhere in your house with a feed button so you can remotely feed and check levels
I'd say no worries at all about freshness, though it could just be my declasse cat's lack of refinement...after all, I buy 25lb-bags of kibble from the warehouse club (Costco) that take my cat months to eat, doled out in 1/4C increments, so &quot;fresh&quot; just doesn't enter the dinner conversation. <br> <br>I bought a commercial version of this that's got some near-fatal flaws - I think your auger feeder is the way to go. The commercial version has overly-flexible paddlewheel-configured 'fingers' on a gear with just four quadrants, and cats that are smarter than mine are apparently known to reach up in there after more kibble and be rewarded - and it's all downhill from there. I originally bought it to keep Squeakers fed while I was off traveling for a month (don't worry, neighbors were alerted to check every so often &amp; notice if she came begging - she also had an automatic waterer of my own construction)... but that was three years ago now, and both feeder and waterer are working still. <br> <br>In kitty-psychology terms, I like removing myself (to an extent) as the entity that feeds. My cat's a terrible beggar, and I found out when I got her as an adult that she will gorge herself into obesity if given the opportunity. The auto-feeder gets mad props for regulating her intake (2x1/4C per day) and getting her weight down to where it should be - and she doesn't go after me or the wife nearly as much for snacks, since we are not often associated with &quot;that weird thing that spills out food twice a day.&quot; <br> <br>
That is excellent. I haven't had a cat for years but when I did I overfed them - I see now. It would sort thru the bowl then pick up the peices It wanted off the floor. Usually I'd wait till the bowl was about used up before refilling. You got great advice there. I really get a kick out of Those that put 2 + 2 together and figure out how to &quot;Beat the System&quot;.! Thank You. G-G
A bit of &quot;Catnip&quot;.? Har.! I think what You've got going will be great for times People can't be there to feed them. Yup.
It's a beautiful invention and gorgeous, but it is very difficult
Excellent 'ible! Not so accessible but I now have access to a 3D printer so I might just try it out! <br>Might I suggest some kind f arduino to control it?<br>My youngest sister has a cat-sized dog so the size should be fine without having to worry about &quot;freshness&quot; :P
Congratulations on being a winner in the digital fabrication contest!
Thanks, maybe I'll get some more filament for the printer
Awesome! After visiting Instructables for about 2 years now I was compelled to comment on this project! It is awesome, and I hope the feeder works as you want it to. The 3D printer does impressive work, and the CNC router is pretty nice too. Thanks for sharing your project, and I wish you many more! -fab
Well I hope it may also compel you post an instructable of your own, two years is a long time to just lurk. thanks for the compliments
As a person who uses a CNC milling machine regularly, my suggestion is that you plan out the cuts, rather than just say, &quot;Here's the part, cut it out.&quot; A lot of the work in our programming department is in planning the machining order. If I were to run your current design, I would start with the slot between the parts, then go to the inside circles, then finish everything BUT the opposite edges. Then, lastly, finish the remaining edges. The code images look like an autistic person's drawing because it jumps around from feature to feature, but it makes for parts that are much less likely to jam up the way you describe and still saves on material. I would also recommend tabbing the material that is to be cut out. It is a lot easier to hand sand a 0.5 x 0.025 tab than to sand out the marks where the tool gouged the part.

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