"SAND" as Heatsink??

[brimstone555]

Hi,

has Anyone considered using Fine Sand as a Heatsink for home made bator?

(the Heat source is 100 watt Globe). I read here that water in a Jar is best Heatsink (I'm using a Water heater Thermostat, but Fluctuates TOO Much!!) So Now I'm considering Sand or small piece of Firebrick... Maybe lay out Flat on Bottom in Tray?

Any suggestions or advice is most welcome... I'm still new to this, but I'd love to prove my little project @75%+ hatch 1st Go!!...

Cheers

 

[Ridgerunner]

Technically what you re talking about is Thermal Mass, not Heat Sink. I got chewed out on this forum for that mistake. At least he was reasonably gentle with me. Well, sort of gentle.

I have not done it but it should work. Anything that adds thermal mass should help once it gets to the proper temperature. I don't know the relative conductivity of water versus sand. The sun warms the land up faster than bodies of water, so I'd think water may be better, but then there may be something else at work than pure conductivity with the sun warming them up.

It sure sounds like you have a homemade incubator. I don't know what it looks like, but I'd probably look for ways to put a container of water in there instead of sand. I'm thinking more on the thought of getting things dirty than anything else. If you do use sand, maybe you want to sterilize it, maybe by baking it in a grill.

Just some random thoughts but no real experience.

Good luck!

 

[Clay Valley Farmer]

Though sand might sound like a good idea, the closed container of water is better.

Water has a very high specific heat capacity (4.187 kj/kg/deg C)
Sand is much lower (0.830 kj/kg/deg C)

What that says is that you will need 5lb of sand to store the same heat energy as 1lb of water.

Dry sand is about 1.75 times as dense as water but that still leave you needing about 3 times the volume of sand to get the same heat storage capacity. Even using solid rock or brick you need 5 times the weight or about twice the volume compared to water.... Strange but true.

Also the sand may cause you problems with keeping the desired humidity as the sand will have a very large surface area to either absorb or evaporate moisture into the air. Though that could be solved by puting the sand in a plastic bag.

 

[brimstone555]

Thanks for the good advice & information I only considered the sand because it's a tiny home made bator just 11 X 9 X 9 IN. I gotta fan inside but Water Heater Thermostat still fluctuates too much! But just found out I can drill a few holes into it for better control... However I still like the idea of perhaps lining Polystyrene with Silicon & Sand that way it shouldn't affect humidity... Not really enough space for water except small container at bottom... Anyway it's all done on the cheap, the most expensive parts were auto turner which I made myself... (needed a timer relay for DC motor!) ..building an incubator that costs peanuts and with "no" clues is challenging... after a few weeks I'm getting there... hehe.. I'll post it when finish and thanks for your support, cya..

 

[platinum dragon]

wow. i would have never guessed

THANK YOU

 

[Clay Valley Farmer]

An easy solution in tight spaces might be to put some water double bagged in ziplocks. By volume water is by far the best storage medium for heat energy. It is hard to imagine that a small 1 quart milk carton of water weighing just over 2 lb would store 17% more heat energy than a solid block of steel weighing about 16lb.

Found this table here at the end of the link. http://en.wikipedia.org/wiki/Specific_heat_capacity

11x9x9 wow, I just finnished up one about 14x14x26 and found it hard enough to get everything plus a couple dozen eggs into it. I think I will plug it in tonight and start a clutch tomorrow, maybe hatch a few silkies a couple EEs and some crosses, Cochin x Brahma and Brahma x RI

 

[A.T. Hagan]

This has been the most fascinating thread. Thanks to Clay Valley Farmer for the info!

 

[Clay Valley Farmer]

Good discussion!

Another neat thing you can do with the water is use it to boost the eggs to temperature. Cool eggs going into a small incubator can cause it to struggle to come to temperature and balance out or really large batches of eggs going into a well insulated but low power incubator can also have trouble comming up to temp.

To do this weigh or guess the weight of the chicken eggs (2oz per large egg) and check the temperature of the eggs before they go in.

Then if you had a dozen large eggs for example that were at 60F you would have ~24 oz that needed to be warmed by 40 degrees or 960 oz degrees. If you took an equal weight of water and heated it to 140 degrees you would be balancing the heat in the the incubator so that the chilled eggs and heated water would equal out as thermal capacity of egg is pretty close to that of water. This will help bring the eggs to temperature quickly using the lights or heat elements only to build and maintain the incubator air temperature.

If you only had room for only 12 oz of water heating it to 180F would do the job, if you had 48 oz then just 120f would work out to the same heat energy. 12oz x 80f = 960 oz degrees or 48oz x 20f = 960 oz degrees ect.

 

[latebloomer]

i used pieces of stone, but sand sounds great.

 

[brimstone555]

yep! thx clay valley farmer

, it is an interesting topic agreed...

the 11x9x9 came about cause that's the box I found.. but realise it's probably too small, but if successful over next month that'll be great right? Thought about the sand cause I work in a furnace and got access to fine grade glass sand.. But water sounds better, hmm so a few zip bags sitting on floor of bator should maintain better temps after a while? while I'm here... here's a pic to show relative size I'm working with... Tricky!! Take care & appreciate the info