BillJ's incubator upgrade

[BillJ]

Started with a plastic storage box, divided and insulated, lamp heater on one side and adjustable speed computer fan, two openings in the divider air-in and air-out with the lamp and electronics behind the divider, relatively precise temperature control with homebrew circuit and a triac module. Scavenged parts, gears/plastic from a VCR, motor drives wooden wheels with rubber bands to step down speed, only drives from one side to the other then shutting down until timeout and reverses. That and more homebrew electronics got toggling 6 eggs 45° on a platform every 2 hours or 4 hours. There's a tin from a frozen lasagna tray fitted to the bottom for the last days extra humidity. The egg tilter fits in and gets removed the last days. Other wise just a cup of water in a corner refilled by tube from outside periodically.

The egg tilter worked okay but some roos had an extra step in the comb which I attribute to tilting rather than turning.

Trying again this spring but am right now building a rotator. An 8" diameter wheel with wooden spokes cut from plywood. Cut PVC at 45° for oval slices to place in the indices. Will be driving the wheel with a stepper motor and an RPI3+/Adafruit IO combination. My attempts at humidity measurement often failed. One used to be able to get small Springfield temp/humidity thermometers. I would remove the thermistor and humidity sensor and remount on fine twisted wire to hang in the incubator. Humidity sensor would too often fail. This time I'm buying humidity modules and that should improve effectiveness. Although the temperature will still be controlled in an external box at the incubator, the temp and humidity measurements will be sent to my desktop so if changes need to be made, e.g. water added to the internal cups, I can do that.

With the shifting platform I would periodically need to manually rotate the eggs in the half carton and twist them 90°, this to even out the unequal heat distribution. The rotating wheel, moving all eggs relative to the air ports in the divider, and the eggs rolling on their axis, means the egg manual rotation every few days won't be necessary.

With a new platform cut to fit the lasagna tin, I toyed with wheel placement relative to a strong stepper motor I salvaged from an early printer. Looks like its gear isn't removable and will just fit through the plywood platform enough to drive the wheel with out any extra height. Would be close.

But while reading the stepper motor drive documentation I decided to look for a 120 vac 2" gearmotor I've had for years. Found it and put it on test to learn its speed. Turns out to rotate 360° in 30 minutes. Am going to use it but will need to gear it down externally, probably with more salvaged gears. This gearmotor is out of a washing machine and probably identical to that which drive dryer timers as well.

I'll still be using the Raspberry Pi to transmit temperature, humidity, and once around data to my desktop, the once around data from a hall effect module outside the ring.

What I need to know is the optimal egg roll speed, albeit very slow and probably not visible. What I found on PubMed is that static egg incubation depletes the sodium concentration of albumen in the vicinity of the yoke. (Quail) Egg turning reduces the magnitude of the sodium depletion allowing full expression of ion and water transport across the blastoderm into the yoke sac. (Br Poult Sci, 1996 May; Latter GV & Baggott GK). And another article on quail eggs turned 90° hourly showed additional mass at 84-96 hours. (Br Poult Sci, 2008 Sept; De Winter P & Baggott GK)

So, I should do some measurements and get a full rotation every 4 hours, I think.

BillJ

 

[HatchCraft]

Started with a plastic storage box, divided and insulated, lamp heater on one side and adjustable speed computer fan, two openings in the divider air-in and air-out with the lamp and electronics behind the divider, relatively precise temperature control with homebrew circuit and a triac module. Scavenged parts, gears/plastic from a VCR, motor drives wooden wheels with rubber bands to step down speed, only drives from one side to the other then shutting down until timeout and reverses. That and more homebrew electronics got toggling 6 eggs 45° on a platform every 2 hours or 4 hours. There's a tin from a frozen lasagna tray fitted to the bottom for the last days extra humidity. The egg tilter fits in and gets removed the last days. Other wise just a cup of water in a corner refilled by tube from outside periodically.

The egg tilter worked okay but some roos had an extra step in the comb which I attribute to tilting rather than turning.

Trying again this spring but am right now building a rotator. An 8" diameter wheel with wooden spokes cut from plywood. Cut PVC at 45° for oval slices to place in the indices. Will be driving the wheel with a stepper motor and an RPI3+/Adafruit IO combination. My attempts at humidity measurement often failed. One used to be able to get small Springfield temp/humidity thermometers. I would remove the thermistor and humidity sensor and remount on fine twisted wire to hang in the incubator. Humidity sensor would too often fail. This time I'm buying humidity modules and that should improve effectiveness. Although the temperature will still be controlled in an external box at the incubator, the temp and humidity measurements will be sent to my desktop so if changes need to be made, e.g. water added to the internal cups, I can do that.

With the shifting platform I would periodically need to manually rotate the eggs in the half carton and twist them 90°, this to even out the unequal heat distribution. The rotating wheel, moving all eggs relative to the air ports in the divider, and the eggs rolling on their axis, means the egg manual rotation every few days won't be necessary.

With a new platform cut to fit the lasagna tin, I toyed with wheel placement relative to a strong stepper motor I salvaged from an early printer. Looks like its gear isn't removable and will just fit through the plywood platform enough to drive the wheel with out any extra height. Would be close.

But while reading the stepper motor drive documentation I decided to look for a 120 vac 2" gearmotor I've had for years. Found it and put it on test to learn its speed. Turns out to rotate 360° in 30 minutes. Am going to use it but will need to gear it down externally, probably with more salvaged gears. This gearmotor is out of a washing machine and probably identical to that which drive dryer timers as well.

I'll still be using the Raspberry Pi to transmit temperature, humidity, and once around data to my desktop, the once around data from a hall effect module outside the ring.

What I need to know is the optimal egg roll speed, albeit very slow and probably not visible. What I found on PubMed is that static egg incubation depletes the sodium concentration of albumen in the vicinity of the yoke. (Quail) Egg turning reduces the magnitude of the sodium depletion allowing full expression of ion and water transport across the blastoderm into the yoke sac. (Br Poult Sci, 1996 May; Latter GV & Baggott GK). And another article on quail eggs turned 90° hourly showed additional mass at 84-96 hours. (Br Poult Sci, 2008 Sept; De Winter P & Baggott GK)

So, I should do some measurements and get a full rotation every 4 hours, I think.

BillJ

Started with a plastic storage box, divided and insulated, lamp heater on one side and adjustable speed computer fan, two openings in the divider air-in and air-out with the lamp and electronics behind the divider, relatively precise temperature control with homebrew circuit and a triac module. Scavenged parts, gears/plastic from a VCR, motor drives wooden wheels with rubber bands to step down speed, only drives from one side to the other then shutting down until timeout and reverses. That and more homebrew electronics got toggling 6 eggs 45° on a platform every 2 hours or 4 hours. There's a tin from a frozen lasagna tray fitted to the bottom for the last days extra humidity. The egg tilter fits in and gets removed the last days. Other wise just a cup of water in a corner refilled by tube from outside periodically.

The egg tilter worked okay but some roos had an extra step in the comb which I attribute to tilting rather than turning.

Trying again this spring but am right now building a rotator. An 8" diameter wheel with wooden spokes cut from plywood. Cut PVC at 45° for oval slices to place in the indices. Will be driving the wheel with a stepper motor and an RPI3+/Adafruit IO combination. My attempts at humidity measurement often failed. One used to be able to get small Springfield temp/humidity thermometers. I would remove the thermistor and humidity sensor and remount on fine twisted wire to hang in the incubator. Humidity sensor would too often fail. This time I'm buying humidity modules and that should improve effectiveness. Although the temperature will still be controlled in an external box at the incubator, the temp and humidity measurements will be sent to my desktop so if changes need to be made, e.g. water added to the internal cups, I can do that.

With the shifting platform I would periodically need to manually rotate the eggs in the half carton and twist them 90°, this to even out the unequal heat distribution. The rotating wheel, moving all eggs relative to the air ports in the divider, and the eggs rolling on their axis, means the egg manual rotation every few days won't be necessary.

With a new platform cut to fit the lasagna tin, I toyed with wheel placement relative to a strong stepper motor I salvaged from an early printer. Looks like its gear isn't removable and will just fit through the plywood platform enough to drive the wheel with out any extra height. Would be close.

But while reading the stepper motor drive documentation I decided to look for a 120 vac 2" gearmotor I've had for years. Found it and put it on test to learn its speed. Turns out to rotate 360° in 30 minutes. Am going to use it but will need to gear it down externally, probably with more salvaged gears. This gearmotor is out of a washing machine and probably identical to that which drive dryer timers as well.

I'll still be using the Raspberry Pi to transmit temperature, humidity, and once around data to my desktop, the once around data from a hall effect module outside the ring.

What I need to know is the optimal egg roll speed, albeit very slow and probably not visible. What I found on PubMed is that static egg incubation depletes the sodium concentration of albumen in the vicinity of the yoke. (Quail) Egg turning reduces the magnitude of the sodium depletion allowing full expression of ion and water transport across the blastoderm into the yoke sac. (Br Poult Sci, 1996 May; Latter GV & Baggott GK). And another article on quail eggs turned 90° hourly showed additional mass at 84-96 hours. (Br Poult Sci, 2008 Sept; De Winter P & Baggott GK)

So, I should do some measurements and get a full rotation every 4 hours, I think.

BillJ

Sounds like you have quite the talent for building incubators with repurposed items. Not 100% sure I understand your roller design. I have always been fascinated by the fact hatching eggs require movement for optimum hatch rate. I thought I had heard about every theory, but the depleted sodium is new to me. So many of the studies were done decades ago. I rarely see more recent studies . I would have no Idea on the egg roll rate, but traditionally egg would be alternately rotated in opposite directions to avoid continually twisting the chalaza. May be a moot point if the egg are rotated slowly enough.

 

[BillJ]

Thanks for reading and the input. Always interesting stuff to be found on PubMed. One article showed the difference on lighting in the incubator, all dark, 12h on 12h off, fully on 24/7. Turns out 12h on 12h off is a little better than fully on. And regarding temperature, another article showed raising the temperature from 99.5°F to 101.66 for days they call ED4-ED11 was best.

We'll see more if it's law that any research funded with tax dollars at colleges must be free to the public.

I had gone to just pick up a small 7 egg rotating incubator on ebay and drop it in my box but had mistakenly thought the $20 incubators were rotating. When I found the rotating model ran upwards of $150 I decided to build my own rotator. I was going to borrow the simple idea of flat disk rotating with eggs but wanted the eggs to spin as well. So, 2" interior PVC sliced at 45° between the spokes of a flat plywood rotating wheel 8" in diameter was the way I decided to go. A conical base would be best but simplicity won out. So, I tried orientating the eggs round side out hoping it would have that end higher but turns out not much. Keeping the eggs orientated was found to work best if I had the ovals centerline 3/4s toward the trailing edge as the plane of the sliced PVC is somewhat complex. So, reversing the rotation periodically probably won't work

BillJ

 

[BillJ]

I have this on test. My signal conditioning for the Raspberry Pi is shown up top. You might notice a lifted resistor, must clip that out. I've been spending way to much time learning code to put timing for each rising edge, note two hall effect modules and 12 magnets for 24 rising edges per rotation, into a mysql database. I have code to show each interval in minutes. I couldn't get an hour per egg rotation using medium eggs but only ~50 minutes but that will have to do. It was much slower until I epoxied a rubber grommet to the washing machine dial gearmotor gear. Software is nowhere near done. I have yet to write an alarm loop so if two edges are missed it will sound. Still waiting for a temperature/humidity sensor from China, ordered 38 days ago, a DHT11. I later found the ATIMOSOS/DHT22 is more accurate and pin for pin compatible with the DHT11 so ordered one from Amazon 18 days ago only to find that was shipped from China as well and isn't here either. Well, plenty of time before spring.

BillJ

 

[BillJ]

Things went very slowly. Gathering eggs from a young hen, I now have 6 and will start incubation soon. I see that the article on how raising the temperature in the middle of the hatch seems counter to a a poster who says that to get more hens than roos one should store eggs cooler and longer. But it might not be counter to the better weight of the warmer eggs mid-hatch as their sex is likely fully determined by then.

I made the rotating disk out of plywood, but plastic, perhaps printed plastic, would have been better as the plywood warped. I may have left the incubator turned off with the pressure of the gear motor in place instead of locking the gearmotor away from the disk.

The problem with a warp is that the too small magnets started to fail to trigger the hall effect modules as the warp moved them too high. I purchased the magnets off Ebay and failed to fully comprehend the size even tho there was a penny next to the magnets as a reference. So small that to epoxy them to the wheel I first had to glue them to snipped Q-tip shafts then epoxy the combination to the wheel. I finally gave up trying to re-position the hall effect modules height and went to bigger magnets. A desoldering heat gun made quick work of the epoxy to remove the old. But the new seemed huge and too powerful but were made to work. Still I decided to reduce the warp by sanding down the wheel on a disk/belt sander. I also added spray adhesive to the perimeter for better contact with the grommet. That was a mistake. The spray adhesive would clump then stop the wheel rotation when it came in contact with the closely placed hall effect modules. After sanding the perimeter clean it rotates well.

I spent a few days or a week trying to write a python script for an alarm that would sound from the Raspberry Pi speaker. The rising edge detector python program was working okay but I couldn't get out of one loop to another within a script, nor could I get a global variable to speak between python scripts properly.

So I gave up and built an alarm detector with a 4060, a 4020, a 2N3904 transistor, few capacitors, and a piezo buzzer. Selectable for ~27 minutes, ~54 minutes or ~108 minutes, its reset was tied to the hall effect modules signal conditioner to the RPi. The hall effect risetime signal occurs every 24-26.5 minutes with an occasional 27. Problem was the strong magnets kept the signal level high too long, keeping the counter reset high preventing counting to the next signal and worse it loaded down the GPIO signal such that it no longer registered each passing magnet. That was solved by capacitively coupling the counter reset to the GPIO input so the next count started almost immediately and didn't load the GPIO. But, the the piezo buzzer created so much electronic noise that 16x2 display showing DHT11 temperature and humidity got pied, gibberish. So, I put the alarm board on a 9v battery. Thought it was a good idea as it would sound if there were a power failure. I used a LM78L05 but the L stands for 'low cost' not low power. The LM78L05 had a quiescent current of 3ma while my alarm circuit only drew .6ma quiescent and 1.4ma while the alarm sounded. That depleted the 9 volt after a few days. So, getting rid of the LM78L05 I put the alarm board back on RPi 5v and improved my alarm circuit filtering. That worked. Now the alarm doesn't pie the display characters.

Now if I have it running and unplug the gearmotor, an alarm will soon sound, e.g. <27.5 minutes on the fastest timing selection.

The Polar Vortex was followed by an Equatorial rebound and beautiful weather but last night was down into the mid-30°'s again. I've just beefed up the insulation on the incubator box and am adding a second circulation fan. I hope to start stabilizing the temperature this afternoon and start incubation in a day or two.

BillJ

 

[BillJ]

Glad I spent some time on the alarm. I have three time selections, 27, 54, or 108 minutes. I used the lowest for testing as the signal period was roughly 24.5 minutes but varied. It would sound 2 or 3 times in 24 hours but only for a few seconds, 30 seconds at the most, ending when the late signal arrived. This afternoon at 2PM will be the start of Day 3. Reading the morning news and eating breakfast the alarm sounded. I waited. It didn't turn off. Days before starting I put the incubator within a slightly larger plastic box and put slices of insulation between the two. I killed the alarm with the counter reset button and shined a flashlight into the window. Wasn't moving that I could tell but then it's so very slow. Opening the incubator I found a tiny Styrofoam nodule between the grommet on the gearmotor and the wheel. The wheel moves so slowly that without the alarm it could have sat motionless for quite some time.

 

[BillJ]

I had originally thought I might have the temperature, humidity, rotation periodic signal timing all sent to a desktop as well as the local display - these from the Raspberry Pi. the python programming soon became too complex so I contented myself with the local display of temperature and humidity from a DHT11 to a 16x2 LCD display, and the rotation periodic signal timing sent to a linux terminal where I had ssh'd in from a desk. Each magnet triggering a hall effect module would result in the terminal display of the time since the last signal. Works well as does the incubator local alarm. The LCD display program is also running in the background from that ssh session.

At the incubator there's the temperature control built years ago around an LM34. A large LCD display on its box shows either the temperature of the air in circulation out of the incubation area or the Set temperature, depending on the position of a toggle switch.

In addition to those two temperature displays there an old Springfield Precisetemp temperature/humidity thermometer, temperature sensor removed and put on 3' of #28 wirewrap wire and tucked through a hole in the incubator's three layers of plastic observation window.

In addition to those three temperature displays I have a new digital meter thermometer, UPC part number 670924932529, that can read quite a selection of thermocouple wires. It is a dual sensor device and I'm using two wires hanging just above the center of the rotating wheel. One a new thermocouple wire that came with the device and a second from an older, second meter a DM6802b. The two different wires, suspended close together, give very close readings on the new meter having a .1°F display resolution. The older DM6802b has a wire immersed in the partly covered cup of water providing humidity.

So, I've been fairly confident in my box temperature even with the jumps of 1.8°F from the DHT11. Putting in the DHT22 today, I'm happy with the result, the temperature right on 100.0°F most of the time. Humidity is showing high though at 71.1% but then it's still settling after having been opened for the sensor change. If it doesn't come down I'll have to add additional covering to the coffee cup.

From the coffee cup I have clear tubing up, out, over, down, and back up to the top with no air bubbles. From the coffee cup to between the two plastic boxes, in an area without outer insulation, I can see without opening the incubator exactly where between the marks for a full water cup and low water cup the tube level sits. I can also add water to the open tube end without opening the inner incubator lid.

I had built a candler the other day. I wasn't going to check until Day 14 but couldn't resist today, most of Day 11 done. I checked all the eggs in a hurry. Each has a blob, not a globe or circle, with fuzzy material extending away. The blob moves freely in the egg. Either they're all alive or all not.

BillJ

 

[BillJ]

My attempt at a hatch a few years back where I was feeding my last BFCM hen, pretty old by then, soybean lecithin in its feed hoping to fudge the eggs sex to hens, did not go well. The hatch did not go well but I now know why. This hatch I discovered that a potentiometer for fan control was badly heating and effecting the LM34. So the hatch went with too low a temperature and only 2 of the 6 eggs in an egg shifter hatched. Both turned out to be cockerels. I kept them and right now those two are my biggest and I dare say my healthiest roos.

 

[BillJ]

While watching the temperature come back up after the incubator having been open this morning, I saw what appeared to be .4°F jumps in the temperature reading from the DHT22. I was wrong. Moving to a slightly higher set temperature, as suggested by a research article, I see a .2°F temperature resolution. It might even be better than that. Time will tell.

 

[BillJ]

The incubator is tight, hopefully not too tight. If the eggs didn't suffocate for too high humidity so far, and it has generally been over 60%, they might not be getting enough fresh air. Reading other posts on incubators I see some have air vents. Not about to put an air vent in mine, I instead exploited a hose hole for adding water to a bottom tray the last days. I ran an aquarium air hose and fired up the aquarium air pump. This might cause heater cycling more but the last days the pump can be stopped and hose used for water while the CO2 is allowed to rise.