Cast Film vs. Blown Film: Which Stretch Film is Best for You? 

What is stretch film? 

Stretch film (or stretch wrap) is a thick stretchy plastic made from polyethylene.  Stretch film comes wrapped around a cardboard roll and is primarily used in industrial settings.  Stretch wrap is a great solution for when you need to securely wrap a load to a pallet so it can be transported or stored safely. 

Standard Films: Cast Film vs. Blown Film

Stretch films are available in specialty or standard films.  Standard films are differentiated between cast film and blown film. Cast film is more popular than blown film.  It is the film of choice for 90% of users. Cast film and blown film are manufactured differently and have a different extrusion process.  The differences between the films are slight but significant.  

• Clarity:  Cast film has better clarity than blown film. This makes cast film a better choice for loads with writing or labels underneath the film that need to be read or scanned. 
  
  
• Noise:  When unwinding, cast film is quiet. Blown film on the other hand makes a loud noise that can be heard throughout the warehouse. 
  
  
• Puncture Resilience:  Blown film has greater puncture resilience than cast film. Blown film is less likely to be poked through or torn. 
  
  
• Load Capacity:  Blown film is a stronger film due to the way it is made. The strength of the film runs both horizontally and vertically on the film which allows it to handle heavier loads.
  
  
• Material:  Blown film is made with an adhesive that is sticky to the touch. In warmer environments the adhesive will rub off on the user’s hands.  This can be a nuisance in a warehouse where a sink or bathroom is not quickly accessible for the user to wash their hands after using. Blown film performs better in a cold environment. 
  
  
• Stretch:  Blown film will typically stretch more than cast film, however it requires more force to do so. Films that stretch further allow the users to wrap more pallets with the same amount of film given that they stretch the film to it's fullest extent.
  
  
• Cost:  Blown film is typically slightly more expensive than cast film.  However, the stretchiness of blown film can get you more with less, so there is not a significant difference in cost savings either way. 
  
  

When to use cast film vs. blown film? 

In most cases both cast film and blown film can get the job done.  However, loads with sharp edges are typically better suited for blown film.  The stretchiness/resiliency of blown film makes it less likely to puncture on sharp corners.  If the speed of which the pallet is wrapped is important, cast film is typically a better choice.  The adhesive in blown film makes it more likely to grab/catch onto itself during wrapping.  This makes adjusting the path of the wrap more difficult, especially when wrapping at high speeds.  Cast film clings but does not grab, which makes it much easier to adjust on the fly.  

Popular styles of cast & blown film: 

      18”x1500’, 80ga, Hexfilm Defender Cast Hand Film - $69.00-$78.00/case of 4 rolls 

      18”x1500’, 80ga, Hexfilm Dynamo Blown Hand Film - $76.00-$82.00/case of 4 rolls 

What gauge do you need? 

Different films will have different gauges (ga).  Gauge measures the thickness of the film.  Gauges of stretch wrap typically range from 24ga to 120ga.  The higher the gauge, the stronger & thicker the plastic will be.  The gauge of film that is right for you depends on the application and is best learned through trial and error.  80ga is the industry standard and can hold/secure loads up to 2,400lbs.  However, due to down gauging in the industry, manufacturers have been able to strengthen lower gauge film by infusing different types of plastic into the polyethylene.  These days you can find 40ga cast films with the same strength as a traditional 80ga.  By down gauging, manufactures have been able to cut costs and lower the price of stretch wrap.  Typically, down gauging is only done with cast film.  Down gauging blown film is not popular as they have not found a plastic that significantly strengthens blown film.  

Pre-stretched Film:

Pre-stretch film is a different type of wrap.  Pre-stretch film is fully stretched out before it is wrapped around the roll.  It will not stretch while wrapping the pallet. Pre-stretched film is lighter than traditional stretch wrap and offers increased load stability.  Because the film is pre-stretched, it guarantees that the user gets the most out of every wrap.  With pre-stretch, less film is used per wrap which results in cost savings.  

      16”x1500’, 33ga, Hexfilm Fortress Pre-stretch Blown Hand Film - $33.00-$39.00/case of 4 rolls 

Wrapping Pallets:  Hand vs. Machine

Hand wrapping is the most common choice for smaller operations who are only wrapping a few pallets a day.  However, for high volume users, a pallet wrapping machine might be a good option for you.  Pallet wrapping machines have a high initial cost as the machine itself will be expensive.  However, it will save time in the long run, and will produce a more consistently wrapped pallet.  Hand wrapping can be a strenuous and tiring job.  It also takes time away from the user who could be using their time to take care of additional tasks that need completed in the warehouse.  

If you are interested in purchasing a machine, the Eagle and Pilot Pallet Wrapper are great options.  The user will have to go through some initial training, but overall is easy to operate and will help to efficiently wrap multiple pallets in a short period of time.  

      Eagle and Pilot Pallet Wrapper - $7,650.00-$8,500.00/each 

For those who are wrapping multiple pallets a day but can’t quite justify spending the money on a pallet wrapping machine, a film dispenser would be a great option.  Simply lock the stretch wrap into the dispenser and grip the handle as you walk around the pallet that is being wrapped.  The lightweight, ergonomic design makes it the ideal tool for effortless/efficient manual wrapping.  

      Grip Film Dispenser - $77.00-$94.00/each 

How to Wrap a Pallet by Hand:

• Choose the pallet on which you will be loading your material. Make sure the pallet is large enough to safely hold all the material that needs secured. 
  
  
• Load items onto the pallet in an organized manner.  
  
  
• Heaviest items should go at the bottom of the pallet.
  
  
• Confirm that there is no space in-between each item as this could cause the products to shift during transport, resulting in damaged product.
  
  
• Choose your preferred style of stretch wrap and begin wrapping your load by hand or with a dispenser.
  
  
• Start from the bottom of the pallet. Many people like to anchor the wrap by tying it to the corner of the pallet. 
  
  
• Wrap your load around all the way up to the top of the load. Once at the top, wrap the material one more time all the way back down to the bottom.  
  
  
• Secure the load by wrapping underneath the pallet once again and tucking the excess stretch film underneath. You may tie the film to the bottom of the pallet once again if you so choose. 
  
  
• Check your load stability to make sure that nothing will fall, shift, or break during transport. 

Would you like to talk to an expert about stretch film products? Call one of our associates today.