New HowTo Video Posted to our youtube channel: screened inner covers

# Thread: New HowTo Video Posted to our youtube channel: screened inner covers

1. ## New HowTo Video Posted to our youtube channel: screened inner covers

Hey fellow beeks. I have posted our latest howto video on our youtube channel. It is a step by step on building your own screened inner hive covers. Feel free to take a look, or checkout all our other howto videos. Make sure you subscribe and turn on notifications to be made aware of new videos, including our free monthly product giveaways!

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## Re: New HowTo Video Posted to our youtube channel: screened inner covers

What exactly does this do over just putting thin shims under the cover? Shims furnish the same ventilation cross section and the area is small enough that most insects can't get through. I put pennies under the four corners. Cost: 4¢. Time: 4 seconds.

4. ## Re: New HowTo Video Posted to our youtube channel: screened inner covers

Originally Posted by JConnolly
What exactly does this do over just putting thin shims under the cover? Shims furnish the same ventilation cross section and the area is small enough that most insects can't get through. I put pennies under the four corners. Cost: 4¢. Time: 4 seconds.
You are 100% correct in that it does keep "most" insects out...though not the important ones, like ants and small hive beetles which can easilly fit in the gap created by a penny.

The second and bigger advantage is the amount of airflow. A Penny is 1.52mm (0.056 inches ) in thickness, and if we do the math that gives you 2.24" + 1.82" = 4.06 square INCHES of space to allow airflow (on a 10 frame hive), but since that space is constricted to 1.52mm in one dimension, it might as well not exist.

The square area of a screened inner hive covers airflow is 19 1/8" x 15.5" (on a 10 frame hive) 2.06 square FEET.

If you know anything about cars or your air conditioner at home, you know that the more clogged your air filter gets, the less air it allows through. When the filter becomes clogged it loses effectiveness and must be cleaned to open it up again. The same principle applies here. The pennies dont provide any cooling effect to speak of AND also open the hive to small insects.

Regardless, my point of the video isnt in trying to sell you screened inner covers, it is to teach other beekeepers how to make their own equipment. All of my videos on youtube do this, teach people how to make beekeeping equipment. Use it if you like. If you are happy with pennies then by all means continue to do so.

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## Re: New HowTo Video Posted to our youtube channel: screened inner covers

Originally Posted by FunnyBugBees
You are 100% correct in that it does keep "most" insects out...though not the important ones, like ants and small hive beetles which can easilly fit in the gap created by a penny.

The second and bigger advantage is the amount of airflow. A Penny is 1.52mm (0.056 inches ) in thickness, and if we do the math that gives you 2.24" + 1.82" = 4.06 square INCHES of space to allow airflow (on a 10 frame hive), but since that space is constricted to 1.52mm in one dimension, it might as well not exist.

The square area of a screened inner hive covers airflow is 19 1/8" x 15.5" (on a 10 frame hive) 2.06 square FEET.

If you know anything about cars or your air conditioner at home, you know that the more clogged your air filter gets, the less air it allows through. When the filter becomes clogged it loses effectiveness and must be cleaned to open it up again. The same principle applies here. The pennies dont provide any cooling effect to speak of AND also open the hive to small insects.
There is a problem with your thinking which led to a problem with your math. You didn't get the penny shim ventilation cross section right and you grossly overstated the actual ventilation cross section your screened top board provides. I'll wait and see if you work out the right effective ventilation cross section numbers. Since evaporative cooling in a hive is a thermodynamic problem it is much more complex than just exchanging the air. The exchange of water vapor that is in the air is a much bigger factor, and exchanging too much air defeats the effectiveness of evaporative cooling.

6. ## Re: New HowTo Video Posted to our youtube channel: screened inner covers

Originally Posted by JConnolly
There is a problem with your thinking which led to a problem with your math. You didn't get the penny shim ventilation cross section right and you grossly overstated the actual ventilation cross section your screened top board provides. I'll wait and see if you work out the right effective ventilation cross section numbers. Since evaporative cooling in a hive is a thermodynamic problem it is much more complex than just exchanging the air. The exchange of water vapor that is in the air is a much bigger factor, and exchanging too much air defeats the effectiveness of evaporative cooling.
You asked for reasons. I gave you the reasons. The amount if any my math is off is minuscule in the grand scheme of things. So let's suffice it to say that you were given the reasons, and don't like them, and would now prefer to be confrontational?

if we take the height of a penny which is 0.056" and multiply that by the four sides of a 10 frame hive, you do indeed come to a conclusion that the penny provides an air space of the following size:

0.056 x 19.125 x 2( long runs of boxes) = 2.071 inches
0.056 x 16.250 x 2(short runs of boxes = 1.82 inches
This gives you a total space air can pass through of 3.891 inches square

This isn't rocket science, basic formula to determine the square area of space, LxW=Area squared

Now with the screened inner cover, you have a space that is 15.500 inches x 19.125 inches, which following basic math gives us an LxW for the square area of 2.88 feet squared. In addition to that there is a smaller spacing in play here, namely how high of your telescoping top sit above the inner cover. With this design that space is 0.375 inches all the way around. So you still have a constricted space to prevent to much airflow, but the hot air inside the hive is more able to be passed up into the ventilation space due to the absence of a standard lauan plywood inner cover. Instead have a space above the bees that is a screen, and of a size capable of allowing good air flow.

Next, I think we need to decide which law of thermodynamics we are quoting here. If you need time to study up on it, ill wait for your reply. Let it be known though that you don't seem to know thermodynamics as it applies to the evaporation of fluid. Since you are putting forth the argument that too much airflow is counterproductive when this simply isn't true.

Evaporation is a type of vaporization which occurs on the surface of a liquid as it changes into the gas phase. The surrounding air must not be saturated with the substance being evaporated, or else evaporation ceases. Evaporation will only go on until an equilibrium is reached and this happens when the evaporation of a liquid is equal to its condensation. Not removing the product of evaporation (by more airflow) is a sure way to ensure you reach that equilibrium and therefore stifle your cooling efficiency.

What this means is that removing the products of evaporation to prevent the equilibrium being reached with its condensate is most important if you want cooling to continue. Therefore more airflow is better, as it removes the evaporated liquid faster. Keep in mind its not the product of the liquid that is evaporated that causes the cooling effect, so there is no reason to keep those products in the hive. They released their thermal energy the moment they phase transitioned from a liquid to a gas.

Anyway, talking this long about condensate, evaporation and thermodynamics wasn't the point of the topic I made, so entertaining your need to almost but not quite be superior has bored me. Again the video stands as a howto on screened inner covers, it requires no more conversation, use it or not, its up to you. For the rest of us that just like to build stuff, and be self-sufficient, we will just keep carrying on.

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## Re: New HowTo Video Posted to our youtube channel: screened inner covers

there is a smaller spacing in play here, namely how high of your telescoping top sit above the inner cover.
Now you're starting to get there. That cross section is the only one that matters. But your first claim was patently inaccurate, the cross section of the hive body is not your ventilation area, no more that it is the ventilation area with any other kind of shim.

Mine have got four pennies on them, except for the ones that have upper entrances, I don't shim them as its not necessary. It works very well. As for ants and other insects, they can just as easily get in through other parts of the hive, especially if you also use a screened bottom, so that advantage is moot. My hives sit on ant proof hive stands. Luckily SHB is not a big problem here
Last edited by JConnolly; 07-06-2019 at 12:59 PM.

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## Re: New HowTo Video Posted to our youtube channel: screened inner covers

Maybe i'm just a brute but that inner cover would not last long in my apiary. You should do another one with a plywood center and then do a 4x4 or such hole in it that you screen. That one seems flimsy on the edges.

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