1. Pouch Thickness. 
   
   Pouches are available in a variety of materials and thicknesses.  Generally most consist of an inner layer of heat sealable thermoplastic such as polyethylene or Surlyn.  These materials also act as a moisture barrier to prevent dehydration and freezer burn.  The inner layer is laminated to an outer layer of gas impermeable material such as nylon.  A third layer of material, such as aluminum, often sandwiched between the first tow may be added for specialized purposes such as protection as light.
   
   Cumulative thickness of the layers should range between 3 and millimeters (.003 - .006).  Bags thinner than 3 mils, while initially appearing to hold a vacuum, are likely to permit some exchange of air, moisture or both directly through the material over a period of time.  Excessively thin bags are also more readily subject to puncture during handling.
   
   Pouches measuring 3 millimeters in thickness are in wide use and are sufficient for most applications.  Since they are readily available and relatively inexpensive they are commonly used for fish, boneless cuts of meat, cheeses, soups, and sauces.
   
   Thicker pouches, 4 to 6 millimeters in thickness, are ideal for food items containing pointed bones (ribs, T-bone steaks), sharp ridges (crab legs) or items subject to rougher shipping and handling.
   
   Pouches thicker that 6 millimeters, while sealable on the VacMaster units, are generally reserved for specialized applications such as medical equipment where goods need to be kept sterile and in some instances, sterilized inside the pouches.
    
2. Pouch Size. 
   
   The most economical and efficient pouch is the one that best matches the product size.  To determine the optimal pouch is the one that best matches the product size.  To determine the optimal pouch size, use the following formulas:
   
    

   Block Shaped Products	Pouch Width = Width + Height + 7/8" Pouch Length = Length + Height + 1-5/8"
   Tubular Shaped Products	Pouch Width = 1.5 x Diameter + 7/8" Pouch Length = Length + Diameter + 1-5/8"

Make it a habit to load the pouch carefully keeping the sealing as clean and dry as possible.  Although the VacMaster can generally seal through the liquids, a clean dry sealing surface will always result in a seal with the best integrity and appearance.

1. They function as a platform so that thinner items can rest flat at about the same height as the sealing bar.
2. They occupy unneeded volume.  This will allow you to set the pump timer to a lower setting without compromising the ultimate vacuum level.  In other words, filling excess areas in the chamber with plates, displaces air and allows the pump to reach its ultimate vacuum level on a faster, more efficient cycle.

Lay the bag in the chamber so that 1/2" to 3/4" of the open end of the bag is resting evenly across the seal bar.  Check the bag to make sure that the sealing surface is as free of wrinkles as possible.

When packaging multiple pouches in the same cycle, align side by side, but do not overlap, the seal area.

In most cases, the objective is to select the minimum time setting which will allow a full vacuum to develop (the guage steadies at 28-30" Hg).  This is influenced by several factors including the two following:

1. Amount of empty space remaining in the chamber.  The more space left unfilled either by product in bags or filler plates, the more air which must be evacuated and the longer it will take to reach full vacuum.
2. Moisture content of the product.  As a general rule, the higher the percentage of moisture in the product, the higher the setting may need to be adjusted.

NOTE:  The gauges on the VacMaster are built and designed with a +/- 2% accuracy and they are calibrated for sea level conditions.  Your actual gauge reading may vary depending on altitude above sea level, as well as the variance from nominal of your particular gauge.  Learn to use the gauge as a relative indicator of vacuum level only.

Seal Bar Timer (right control knob).  The seal bar timer is a 0-3 second timer.  The more the know is turned to the right, the longer the power (heat) will be put to the seal bar and the thicker the pouch material that can be sealed.

A timer setting that is too short will result in an insufficient seal and the bag will leak within a short period of time.  A timer setting which is too long will result in a burn through the bag in the area of the seal. 

At this point, the automatic cycle begins.  As you watch the gauge, you will see the needle move up from 0 toward the 28-30" mark.  If you look at the pouch in the chamber, you may notice that the bag actually appears to "puff-up" at first.  This is normal and in fact, indicates that the pump is working efficiently.

If you have set the pump timer correctly, the needle should reach the 28-30 mark and then "dwell" there, with the pump still running, for 2-3 additional seconds before the seal bar indicator clicks on.

NOTE:  If the pump stops (only on gas flush models 20 and 20) and the seal bar indicator comes on before the gauge has steadied, then this indicates that the vacuum level achieved will be less than optimum.  You may want to increase the pump timer setting to the next level and try again.

On the other hand, if the gauge steadies and the pump continues to run significantly longer than the 2-3 second dwell, then you can conclude that no higher vacuum level will be achieved, the machine is just "idling" and that the pump timer can be decreased slightly for the (faster, more efficient) next cycle.

When the seal bar indicator light comes on the seal on, the seal bar raises up, pinches the bag shut and heat seals it.  Once sealed, the de-vac valve opens and air re-enters the chamber.  Since the inside of the bag is still at vacuum, the atmospheric pressure of the outside of the bag will collapse it tightly around the product.

The lid will open automatically.

CAUTION!  The seal bar will still be hot.  DO NOT TOUCH!

Depress the red quick stop button to terminate evacuation at the very moment the boiling begins.  The VacMaster will immediately stop and heat seal the pouch.