About the BBB
The Genesis of the name BBB
(Boyle's Bubble Buster)
Boyle's Bubble Buster is our nickname for the Gel Candle Debubbler. It is named in honor of Robert Boyle (1627-1691). Boyle was a chemist and a natural philosopher. He was noted for his pioneering experiments on the properties of gases and his views of matter. His work led to the modern theory of chemical elements. While at Oxford Boyle collaborated with Robert Hooke in constructing an air pump with which he conducted the experiments leading to his publication (1662) of the relationship, now known as Boyle's law, that at constant temperature the volume of a gas is inversely proportional to its pressure. The complete story of the origins of the BBB can be found in the article Bubbles and Gel Candles which can be found at http://www.belljar.net/034gel.pdf. The current version of our vacuum debubbler is known as BBB3.
Overview of the BBB3 Vacuum Debubbler
The BBB has been developed specifically for maximum elimination of bubbles in gel candles. Nothing works as well and as dependably. Vacuum debubbling is a standard technique in industry for eliminating bubbles in plastic moldings and potted assemblies where the presence of bubbles could cause anything from performance problems to catastrophic failure. The wide use of vacuum debubbling is a testimony to the efficiency of this method. While other techniques can work under some circumstances, only the application of vacuum technique can assure consistent success and productivity. The team of Deb Puerini and Steve Hansen have developed a simple to use system, the BBB, that will make the production of beautiful, clear gel candles an easy and relatively straightforward task with immediate results and no guesswork.
The BBB3 consists of two major parts: the vacuum pump and the chamber/manifold assembly. We do not supply the pump but a recommended pump can be purchased through the Order page on this site.
The chamber/manifold assembly (the parts we supply) consists of a vacuum tested aluminum chamber with vacuum gauge, tempered glass viewport, vacuum hose and a special fitting for the vacuum pump. A full set of detailed instructions on how to set up, safely use and properly maintain your BBB is also included. The picture below shows a typical set up. (Note, in the current offering, the gauge is mounted to the chamber.)
What Goes On During the Debubbling Process?
When gel is prepared the mixing process introduces tiny amounts of air. In addition, embeds that are inserted into the gel will also carry with them some amount of air. The whole idea of the BBB is to use vacuum to make the trapped air bubbles expand, float to the surface and break. The amount that the bubbles expand is directly related to the change in pressure in the vacuum chamber. When the pressure gauge, which is calibrated from 0-30 inches of vacuum, reads 29 inches a bubble will expand by a factor of 30. As noted before, this relationship between pressure and volume was discovered by Robert Boyle and is referred to as Boyle's Law. The degree of vacuum is critical. Simple vacuum pumps such as those supplied with food dehydrators will not work properly. The only suitable pumps are oil sealed rotary vane pumps. When debubbling you place the melted gel in a glass beaker which, in turn, is placed in the debubbling chamber. The chamber is closed and the pump turned on. By means of a special pressure control valve you drop the pressure to a point where the bubbles start to expand and rise. Initially this can be quite vigorous. As the bubbling slows down you adjust the pressure even lower to get rid of all of the bubbles. The whole process only takes about 3 minutes. The picture below shows a batch of gel that is being debubbled.
What's Requred to Maintain a Vacuum Debubbler?
The BBB requires very little maintenance. Just keep all of the parts clean with an occasional wiping with a clean, dry, lint-free cloth. For a more thorough cleanup, if required, you may use warm water with a mild, pure & unscented soap (e.g. Ivory dish detergent). Do not use solvents as these may attack the seals or plastic surfaces. If water has been used for cleaning, make sure all surfaces are dry before using with the vacuum pump. Water will contaminate the pump oil instantly. The most important part of maintenance is keeping the pump oil clean and at the proper level. Before each debubbling run make sure that the oil level is midway in the sight glass. We recommend that you change your oil on a monthly basis or more often if the oil appears darkened (dirty/contaminated) or milky (a sure sign of lots of water content). Suitable vacuum oils are usually obtainable locally but high quality oil may also be purchased through us. We can also supply miscellaneous spare parts such as o-ring seals, extra tubing, etc.
©2008 Stephen P Hansen, the Bell Jar