Thermometer/temp CRAZINESS!!

[flyweed]

WOW...who knew my thermometer question would start a heated (no pun intended) debate!

Anyway, do you guys think my "egg wiggler" idea will work? Instead of a water wiggler, I used a chicken egg..I blew out the yoke, filled the egg with water, inserted the probe, and then hot glued over the holes...won't this give you a pretty accurate "inside egg" temp reading that we are looking for?

Thanks
Dan

 

[twigg]

Quote:
I would think that would work well.

 

[WalkingWolf]

You will probably need to seal the egg shell as it will probably evaporate water just like a real egg. I liked the idea of using modeling clay in the shape of an egg and will try that on my next set.

BTW come Easter you should be able to find a plastic egg...

 

[WalkingWolf]

none taken.

Please stop with the *my thermometer is bigger than your thermometer* stuff tho, it doesn't help.

I am trying to help you focus on what is important here. In the end tho, you have to do what you think is best. FWIW, I think you are misleading yourself a bit, but time will show you the way you need to go.

Good luck. With the amount of care you seem to be taking, I'm sure you'll do fine smile

Actually a oral thermometer is not very big...

I used a water wiggler on a set of 6 duck eggs. When the eggs started pipping 2 days and hatched 2 days early I knew something was up. Also only had 2 out of 6 hatch. I asked a lab tech and they gave me a "you used what??". I understand that the water wiggler is close, probably close enough for most. But hatching eggs that have already been stressed from shipping I wanted a little better. At least for my peace of mind, I only make suggestions from what I learned, and some advice from someone who grows cultures for a living.

Nothing to really get heated over...LOL just a different opinion...​

 

[jvls1942]

this is not directed at anyone in particular,so just jump in if you have an answer..

what happens when the clay gets dry and hard as a rock??

I really get a kick out of those who have styrofoam bators.. It is tough enough to get the temp stable, not to mention trying to focus half way down an egg..

the way I see it. the egg is basically liquid.. heat transfers through liquid and if you heat one spot on the egg, the whole egg is going to be the same temp.. anyway, I am a gambler and I will bet that not .oo5% of you have thermometers delicate enough to test this theory.. I, for the first, admit that I do not..

I guess I cannot buy the theory that the temp is different in 3/4 of an inch in height in an incubator.. especially one with a fan..

 

[WalkingWolf]

Quote:
From what I understand the halfway up theory is only for still air incubators, but it doesn't hurt to be safe.

 

[twigg]

Quote:
The clay is not a method designed to be left in an incubator .... it is a method designed to calibrate thermometers, which doesn't take long at all

Wiggler is left in, and works like a charm

 

[Cowboy Joe]

I’m assuming you meant to say Fluker’s not Fluke as someone interpreted the name. Fluke manufacturers some of the best test equipment in the world…and you pay top dollar for the item. Fluker’s, from what I’ve found, is a retail variety device which sells a combo thermo/hygro for ~$12-$20. Is this the device?

http://www.petco.com/Shop/Product.aspx?R=7261&Nav=1&N=0&Ntt=thermometer&sku=401862&familyID=14241&

If so, the accuracy is not very good. The specs say +/- 1F. The end users say it’s closer to +/-2F:

http://www.beefbayo.net/index.cgi?O...on=CustomerReviews&ItemId=B0009YJWW4#review_1

A decent, etched scale alcohol thermometer is ~$8 and is accurate to +/-1.5F. The offset (error) is predictable as these are linear devices meaning if it’s off by +1 at 32F, it’s more than likely off by +1F at 100F. Stick the thermometer in an ice bath and record the difference from 32F. Add or subtract that number to your desired temp and adjust your incubator accordingly. Digital thermometers are non-linear meaning 1F at 32F doesn’t mean much of anything at another temp. One of my digitals reads dead dog on at 32F but reads 5F high at 100F. (This could be due to either non-linearity or the span adjustment…either way 5F is a lot!) Doesn’t matter, unless I have a way to calibrate my digital, I don’t really know how accurate the display is.

My 2¢ for what it’s worth: incubator temp is very dependant upon a couple of variables with thermometer position, drafts, and heater control type (on/off versus proportional) being the biggest players. Digital thermometers, while easy to read, also have the disadvantage of reacting too quickly to changes. Most of the Styrofoam incubators use on/off heating controlling. Like your house, the heat comes on when the thermostat reaches a lower set point and shuts off when the temp exceeds the upper threshold. This means if your thermostat is set to 68, the heat may go on at 67 and shut off at 69. This is known as hysteresis and it is an inherent characteristic on on/off control.

Proportional control is more like a faucet. You can turn it on full to fill an empty container, then close to a trickle when you get close to the right level. Now imagine the cup you are filling has a small hole. The loss of water is comparable to the loss of heat. Maintaining a constant level with on/off control is next to impossible as you either have heat or you don’t. With proportional control, the ‘faucet’ can be set so the water coming in is the same volume as the water leaving.

Anyway, the point is the digital thermometer will pick up all these variations in temp. I have an LG and normally see the temp vary between 99 to over 100, sometimes close to 102 for a minute of two, with a digital thermometer. The natural reaction is to adjust the temp. The alcohol thermometer is much slower to react and does not show the variation so the temp appears to remain ~99.5. What you will see is the average and that’s the primary concern. Remember, a chicken’s backside is not calibrated. The temp will vary with outside temp and as she adjusts herself on the nest. The big no-nos are too high a temp for too long and too low a temp for too long.

 

[WalkingWolf]

Quote:

 

[twigg]

Quote:
Be wary of assuming that the inaccuracy of an alcohol thermometer is linear. Sometimes it is, oftentimes it isn't. It depends on the quality of the glass tube.

Calibrate it at 99.5, and it won't matter what it reads outside a few degrees of this, 'cos we don't need to know

I agree about proportional control, it is vastly superior, and PID control is even better. Both can be had for a modest cost.