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View Full Version : R Factors Glass Vs Plastic


monkeywrench133
03-01-2006, 01:54 PM
Does anyone have any real data on the insulating properties of glass and plastic? Specifically, aquarium glass vs rubbermaid tub plastic.
Hennek
03-01-2006, 02:23 PM
Nope...but the common thought in the fish community is that an acrylic aquarium insulates ~20% better than glass...all I can say is good luck as I doubt you'll find any data set for the rubbermaid.

Although it's a VERY crude experiment, one way you might be able to get a rough estimate is to take a rubbermaid container and an aquarium with approximately the same volume, put a heat source inside (like a bucket of hot water...both need to be same temp/volume/placement/etc), a wireless thermometer inside and finally put a top onto the rubbermaid and aquarium. Use an infrared temp gun to take surface temps and the wireless thermometer to take internal temps every minute or so for an hour...plot the data and the slope will give you a relatively good indication of heat loss.

Matt
monkeywrench133
03-01-2006, 05:45 PM
I'm trying to avoid experimentation, but if it comes to that I'll buy a small rubbermaid and cut a flat piece out of it, then get a small piece of glass and lay each on the same piece of flexwatt, give them 20 minutes to equalize, then hit them with the temp gun.
v2r
03-01-2006, 06:54 PM
in addition to the above, i would use masking tape on the surfaces tested by a temp gun. the difference in surface reflection/refraction (glass) may throw a reading off.


vaughn
Hennek
03-01-2006, 08:35 PM
I'm trying to avoid experimentation, but if it comes to that I'll buy a small rubbermaid and cut a flat piece out of it, then get a small piece of glass and lay each on the same piece of flexwatt, give them 20 minutes to equalize, then hit them with the temp gun.


Not the greatest experiment...assuming they both have good contact with the heat tape, they will both equalize out to the temp of the heat tape quite quickly. To make it a good experiment, heat the tape up to a specific temp, lay the pieces on, then watch the temp rise of each over time...you need to get a rate to determine their insulation capacity.