Posted by: PigTech on May 16, 2003 at 11:00:39 Forum Administrator

: Sorry for being the pain in the butt questions guy, but got a follow up to that. :) No problem. : I come from the principle that an insulator is anything that works as a barrier between what is being held and the environment. That's pretty much it. The definition of insulate is "To prevent the passage of heat, electricity, or sound into or out of, especially by surrounding with a nonconducting material." A materual that does not conduct, or transfer heat well, such as neoprene makes a good thermal insulator - hence its use in wet suits where it traps body heat on the inside rather than letting it transfer to the cold water on the outside. :When there are changes outside of the barrier, the insulator will minimize the effect on what it contains. Yep :When the contents starts to change, the insulator tends have a slow transfer betwen the contents and the insulator itself. What you are describing is thermal capacitance, the ability of a material to act as a storage medium for heat, and then give it up as needed. Insulators have poor thermal capacitance because they are poor conductors. : That being said, I can see your point on warm or hot days after you reach a critical mass point. On a hot day, the insulator will also start off hot and transfer it's heat. But once that is used it, the insulator will tend to prevent further warmth from coming in. No the insulator will very slowly give off heat to something that is colder than it is, and slowly absorb heat from something that is warmer than it is. It is a constant process, there's not a "critical" point. Heat transfers at given rates for any material in a direct ratio to surface area. The exception to that - when there is a critical point, is when the material changes phases, such as boiling from liquid to gas, or melting from solid to liquid. : But my question comes in on COLD days. Say it's 40 degrees and you decide to play with some work horse like Tippmans with CO2. With Neopropoline (sp) covers I assume that the surface temp of the cover will pretty much be warmer than anything outside especially with as much time as a bottomline tank is held against the body. Unless you are naked, no. Because your clothing is also an insulator, the outside of your clothing will be close to the surrounding temperature, and the inside will be close to your body temperature. : So on those 40 degree days with 15MPH wind and sunny skies, will the tank be warmer with the cover or exposed to the elements? That depends on whether or not you shoot the gun. On humid days, I've frosted over CO2 tanks in 65 and 70 degree weather. When the CO2 boils in the tank it is drawing heat from around it, and that heat has to come from somewhere. Shoot only a little bit, and it will draw heat from the tank, and the tank will absorb heat from the air, and it's temp won't drop much. Shoot a lot, it will absorb a lot, and the tank's temperature will drop more, because the air can only warm it up so fast. Insulate the tank, and it will take longer to warm up. : Also, one other point I'll throw out. I myself plan on continuing to use my cammo tank cover. For woods games it makes concealment much easier as it reduces the metalic glare and helps blend in with color. Often with the woods games I play I spend a considerable amount of time amoung the rocks, twigs, and thorns. Other than the hydro date ink being rubbed off, my tank still looks like it's just off the shelf. None of this should be taken to say there are no benefits from neoprene tanks. As I pointed out in another response on this thread there are also the bounce factor and sound reduction benefits. It could well be, that with your style of play, the extra insulation on the tanks isn't causing problems. However, adding a neoprene cover is not going to solve CO2 temperature related velocity problems. At best, it won't have a noticable impact (as in your case) and at worst, it can exacerbate the problem. : Also, with my 20 oz tank, I can pretty much count on 1000 rounds before emptying on the worst day. And since I have 2 tanks, when one runs out, I refill it and use the other tank. : For the way I play and the field I'm at, loosing a couple or even a few hundred rounds of paint per tank is almost an irrelavent loss to give in order to hide easier and protect the tank. Yep. See you on the field, -Bill Mills

Follow Ups: Post a Followup Show your name as: DefaultRealnameBothNickname E-Mail address (eg: joeschmoe@aol.com): Show your e-mail address? DefaultYesNo Your Password: Don't have a password? CLICK HERE - Forgot your password? CLICK HERE Subject: Subject:Message: : : Sorry for being the pain in the butt questions guy, but got a follow up to that. :) : No problem. : : I come from the principle that an insulator is anything that works as a barrier between what is being held and the environment. : That's pretty much it. The definition of insulate is "To prevent the passage of heat, electricity, or sound into or out of, especially by surrounding with a nonconducting material." : A materual that does not conduct, or transfer heat well, such as neoprene makes a good thermal insulator - hence its use in wet suits where it traps body heat on the inside rather than letting it transfer to the cold water on the outside. : :When there are changes outside of the barrier, the insulator will minimize the effect on what it contains. : Yep : :When the contents starts to change, the insulator tends have a slow transfer betwen the contents and the insulator itself. : What you are describing is thermal capacitance, the ability of a material to act as a storage medium for heat, and then give it up as needed. Insulators have poor thermal capacitance because they are poor conductors. : : That being said, I can see your point on warm or hot days after you reach a critical mass point. On a hot day, the insulator will also start off hot and transfer it's heat. But once that is used it, the insulator will tend to prevent further warmth from coming in. : No the insulator will very slowly give off heat to something that is colder than it is, and slowly absorb heat from something that is warmer than it is. It is a constant process, there's not a "critical" point. Heat transfers at given rates for any material in a direct ratio to surface area. The exception to that - when there is a critical point, is when the material changes phases, such as boiling from liquid to gas, or melting from solid to liquid. : : But my question comes in on COLD days. Say it's 40 degrees and you decide to play with some work horse like Tippmans with CO2. With Neopropoline (sp) covers I assume that the surface temp of the cover will pretty much be warmer than anything outside especially with as much time as a bottomline tank is held against the body. : Unless you are naked, no. Because your clothing is also an insulator, the outside of your clothing will be close to the surrounding temperature, and the inside will be close to your body temperature. : : So on those 40 degree days with 15MPH wind and sunny skies, will the tank be warmer with the cover or exposed to the elements? : That depends on whether or not you shoot the gun. On humid days, I've frosted over CO2 tanks in 65 and 70 degree weather. When the CO2 boils in the tank it is drawing heat from around it, and that heat has to come from somewhere. Shoot only a little bit, and it will draw heat from the tank, and the tank will absorb heat from the air, and it's temp won't drop much. Shoot a lot, it will absorb a lot, and the tank's temperature will drop more, because the air can only warm it up so fast. Insulate the tank, and it will take longer to warm up. : : Also, one other point I'll throw out. I myself plan on continuing to use my cammo tank cover. For woods games it makes concealment much easier as it reduces the metalic glare and helps blend in with color. Often with the woods games I play I spend a considerable amount of time amoung the rocks, twigs, and thorns. Other than the hydro date ink being rubbed off, my tank still looks like it's just off the shelf. : None of this should be taken to say there are no benefits from neoprene tanks. As I pointed out in another response on this thread there are also the bounce factor and sound reduction benefits. It could well be, that with your style of play, the extra insulation on the tanks isn't causing problems. However, adding a neoprene cover is not going to solve CO2 temperature related velocity problems. At best, it won't have a noticable impact (as in your case) and at worst, it can exacerbate the problem. : : Also, with my 20 oz tank, I can pretty much count on 1000 rounds before emptying on the worst day. And since I have 2 tanks, when one runs out, I refill it and use the other tank. : : For the way I play and the field I'm at, loosing a couple or even a few hundred rounds of paint per tank is almost an irrelavent loss to give in order to hide easier and protect the tank. : Yep. : See you on the field, : -Bill Mills [ Follow Ups ] [ Post Followup ] [ WARPIG Tech Talk - Model 98 / 98 Custom ]