What does a Carb Cap do?
If you’re a dabber, you may have noticed that when you put a carb cap on your dab you get a thicker hit, but have you ever asked yourself why? In this article, we will discuss exactly what it is a carb cap does and how this leads to a better dab.
Conduction vs. Convection
When you first put your concentrate on a hot surface it is primarily being heated through conduction, the passing of heat through direct surface contact. This is analogous to cooking on a hot pan. Once you carb cap your dab, the concentrate is simultaneously heated through its contact with the hot surface and from convection, or fluid heating. Putting the cap on creates a sealed environment where the air inside is heated as well. As you pull, the trapped in, heated air then circulates and vaporizes your concentrate. This helps achieve more even vaporization since heat is not only coming from surface contact, but from the air as well. Without a cap, the hot air easily rises out of the banger and into the surrounding air and a large amount of cool air is pulled in, so the temperature of the air in the banger is significantly lower. In my opinion, a carb cap is necessary to any good dab, but, if you’re low temp dabbing, this is an absolute must. Not only will it limit pooling of leftover unvaporized concentrate, but it will produce a milkier hit, concentrating the vapor, and producing better flavor.
Effect on air flow
As you pull through your rig, the surrounding, cool air enters your banger mixing with the heated air. You don’t want to completely seal in your dab, because not only will you not be able to pull the vapor through to inhale it, but the air will be so still that convection is limited and little to no vapor will be produced. However, without a carb cap on a banger, more cool air can enter, and hot air is not retained within the environment as heat rises. So, there will not be any convection, as depicted in the diagram of a banger shown. If you’ve used a nail and dome before, a carb cap is really the same concept as a dome. A dome also creates a somewhat sealed environment where the air is heated, and convection can do its work. Typically, though, a dome features a much larger hole than most carb caps seen today. This may be one of the reasons we are beginning to see domed nails phase out.
It is important to consider the size of the air inlet on the cap to balance the drag it adds while still retaining heat to facilitate convection. A carb cap will restrict the air flow through your rig, but it also prevents vapor loss and produces a more concentrated, evenly vaporized hit. In a carb capped banger, the air movement inside your banger causes more interaction between the hot air and the concentrate, further increasing vaporization. Although, some carb caps will restrict airflow more than others which can limit the effects of convection due to decreased air movement. This depends entirely upon the amount of air flow possible while the carb cap is on. Most come with at least a small hole or slit as a fresh air inlet, and the size of this inlet determines the amount of air flow possible.
However, the air inlet can be large enough that you decrease convection through allowing more heat to escape and more cool air to enter lowering the temperature of the air which is heating your concentrate through convection. So, you must balance air flow and keeping a relatively sealed environment. To some extent, this is personal preference. However, as the larger the air inlet, the less sealed the environment is and the less your concentrate will be heated through convection. So, you won’t vaporize your concentrate as evenly. It’s likely that increased vapor density among other factors contributed to this switch from domed nails to bangers and carb caps.
Some carb caps even add extra utility beyond the benefits discussed above. Some can serve as your dab tool. While others, such as the TAG- Banger Bent Stem Carb Cap and other options, that direct air flow can be used to push the concentrate to hot parts of the nail further helping to optimally vaporize your concentrate. So, if you don’t have one already, a carb cap will dramatically improve your dabbing experience through more even vaporization and helping you get the most out of your dabs.