Troubleshooting homemade incubators

[patandchickens]

I am now in my third go with this homemade thingie of mine, and FINALLY I feel like I have ironed out a lot of wrinkles and got it working really reliably and "professionally". (Well, we'll see what my hatch rate is, two weeks from now <g>)

I would like to pass on some of the lessons I've learned the hard way, for others to learn the EASY way i.e. by reading about rather than doing

Some of my problems are undoubtedly due to my incubator being in a cool (55 F) basement, because its temperature is very stable year-round as opposed to any other part of the house; but I think most or all of the following would be equally useful for anyone.

For trouble getting temperature steady/stable:

--Experiment with different bulb wattages.

--Try a low-wattage bulb that is constantly on, with another low-wattage bulb in the thermostatically-controlled socket. I am currently using a 25w always on, and a 40w in the thermostatically-controlled position; but it will depend on your incubator size, insulation, and room temp.- for a warmer room, you would use even smaller-wattage bulbs.

--Try adding thermal mass (I believe it was gopherboy I got this idea from?) - I use three marmalade jars full of warm water, plus one of those little blue 'cool packs' you use in packed lunches because it's thin enough to fit an awkward corner. Plus of course my dish of water for humidity.

--I had problems at one point with a *large* thermal mass (quart mason jar of water) right next to the main lightbulb -- it was causing temps to fluctuate too much. So it is possible to overdo.

--Insulate the bejeebers out of the 'bator. This also lets you use lower-wattage bulbs in it. Mine is has inch-thick styrofoam and several layers of bubblewrap, but my real breakthrough in getting it to Work Real GOod was when I broke down and tied sheets of 4" thick upholstery foam all around it with another one lying on the lid. It looks HORRIBLE - I have to get some pics so y'all can laugh at it

- but combined with all of the above, it now stays +/- 0.2 F of target temperature, woo hoo1; when I open it to manually turn the eggs, it drops to 97-98 F but bounces back to correct temperature within 10 minutes.

For trouble adjusting humidity:

--After trying a whole lotta arrangements, what works most reliably for me is a small casserole dish (the kind you would make 1 portion of mac n cheese in) filled with water with a rag or paper towel sticking out of the middle like a mountain 'island'. If you want more humidity, pull the rag to stand up higher out of the water (can prop with bamboo skewers or whatever); if you want less humidity, poke it further underwater.


I would LOVE to hear other peoples' best tips for improving the performance of a homebuilt 'bator. Because mine could still use work -- I am still not happy with my ventilation situation -- and besides I want to rebuild it totally in a new housing and can use all the good ideas I can find

Pat

 

[Chic Chick]

What I just made is a 1/2" stryofoam one 34" long by 13 1/2 " wide, and I still have to build a wood cabinet for it but so far it's doing as well as I expected. Right now I have it covered with a bath sheet.
I'm currently using a 60 W bulb and have the fan blowing across the bulb and then directly across my water, with my ventilation holes close to the top of the back wall. They can be opened or closed depending on the heat and humidity.
I have a short wall put up to keep the direct heat away from the eggs but it still seems the closest eggs are warmer then the rest of the incubator. My humidity stays steady at about 40.
I've got embryos growing in mine after candling on day 9. 28/36 with only 2 blood rings and the rest were clears.

I could borrow incubators from friends not using theirs anymore but it sure is fun to build one.

 

[aprophet]

This is a pretty neat post I wish I could have read it 2 weeks ago I have done almost all the things you suggestI just found out trail and error my temps stabilized a lot just when I added the fan I built sheet metal baffles that are almost right up agianst my bulbs I think I ma usiing 75-100 watts my bator is 1/2" plywood it has been holding steady the last coupla days

 

[Chook-A-Holic]

When I did my wine chiller conversion I somewhat went a little different route that you. I wanted a backup just in-case a bulb blew. I used 2 bulbs and experimented with different wattages, however what I did was to have both bulbs on the thermostat sized for a fairly quick recovery without overdoing(spiking temps) it but at the same time if one of the bulbs blew out the bulb left would be sufficient in keeping the temps stable. For example, I unscrewed one of the bulbs and it just resulted in a little longer on cycle without losing any heat in the bator. I used 2 2ltr. bottles in the bottom for heat sinks. I also found out that by shutting it off that the heat would remain in the false back due to the fans not pulling the warmer air out while turning the eggs. When turned back on my temps were back up and the bator was off in less than a couple of minutes.

Here is a pic of mine with the rear door open showing the internals of the false back.

For air intake I drilled 4 1/4" holes through the rear door and a medicine bottle cap. I just spin the cap aligning the holes for desired fresh air. It is aligned with the fan to pull in fresh air. I also used the 1/4" holes with bottle cap method for the exhaust air.

Here is a pic of the exterior of the air intake.

Here is a pic of the air exhaust

Here is a pic of the front. As you can see I also put a straw from one of the exhaust hole openings so I wouldn't have to open the door during lock-down to add water. I did use the straw the whole time however I was opening the door 3 times daily anyway to flip the cartons around but it really didn't matter.

I did 4 hatches with this and couldn't have been more satisfied. 100% hatch rates of all fertile eggs. To me it's just one big experiment that is absolutely FUN. My daughter has since talked me out of it for her classroom, so I just called Mr. Dickey and ordered an incubator and a hatcher. I realize that we all may do things a little differently but maybe this will give you some ideas. Good Luck and stay warm!!!

Edit: I just wanted to add that on day 19 I removed the eggs from the cartons and put non-slip shelf liner on top of 1/4"X1/4" for hatching.

Here is the end result of my last hatch.

 

[patandchickens]

Quote:
Oh, that reminds me of another one:

For adjustable baffles (so you can fool with them to get the best configuration): if, like me, you have a vertical wall of hardwarecloth separating the part of the incubator containing the eggs from the adjacent part containing the lightbulbs and water and all that, you can use big rectangular kitchen magnets to stick to the hardwarecloth as rearrangeable baffles. You know, the ones that are like maybe 3"x4" and have logos from pizza places or your insurance company or gov't programs or "in emergency call:" or things like that.

I'm really enjoying seeing what everyone's posting on this thread, keep it coming

Pat

 

[sevenchickens]

I love the Vinotemp incubator. That's brilliant! My Dad just gave us one about the same size, we don't use it, now I know what to do with it!!! Thanks for sharing!

 

[Barred Rocker]

Good advice. I've built a forced air cabinet incubator that's untried as of yet. My temperatures are consistant but it varies in different sections of the incubator. I've using computer fans to deflect hot air away from the too hot areas but only limited success. Also I can get the air temperature about right but my eggometer will read 2 degrees higher. It's aggravating because it's so close but I can't get it just right.

 

[Chook-A-Holic]

Quote:
Look at my 1st pic in post#4. You will see 4 holes(1 in each corner). I started these holes out at 3/4 " and increased their size until the egg chamber had consistent temps throughout. I now have 0.1* difference from the very top to the bottom. There is also a fan on the ceiling blowing air across the water on the top shelf. I set the bator up just like it was going to be running then increased the return hole sizes until they were consistent temps throughout. I was getting kinda worried before finally getting it right due to having to keep some positive pressure in the egg chamber so that the air exchange exhaust vents would properly push out air. I guess you could say that it works somewhat like an open plenum HVAC system found in some older bldgs(not legal anymore) .

 

[Chic Chick]

That's a great idea with the "thermal mass" to help keep the heat constant. I'm going to put a couple jars in the bator and see what that does to the temperature on the far side.
I see movement in the eggs when I candle them, so I don't really want to mess too much with something thats working fine right now.
I have pictures of my incubator on my page

 

[aprophet]

Quote:
normally your air keeping the product hot would have to be a little hotter then the product itself ( eggs) most of the time in A/C the dishcarge air is 20-30* hotter/cooler then what you are feeling. I was thinking of building a slighty larger bator and using some duct board and run a central "duct" 2"X3" 3"X3" aprox. down the middle with a few holes to get better air distribution I saw 1 bator design with 2 fans in sepperate chambers it kina looked like a better design then most it was a cooler with a chamber at each end and the eggs in the middle I think it was Aussie in origin. most of the time when you heat air and do not circulate it the air layers cold on the bottom and hottest at the top . just a few random thoughts LOL