Metal-mounting - Part 4
 
In metal mounting, this holds true:  The larger the volume -- the more simple the solution needs to be.
 
Bubble-wrap stuffed in a packing list is fine when you are packing 10 or 100 shipments.  However, bubble wrap requires too much labor for thousands of shipments.
 
We keep looking for faster, inexpensive solutions to the metal mount situation and have been testing a consistent / easy to apply sponge/foam solution.
 
Wal-Mart Stock
Sponge Tape
Our first test was with a Wal-Mart
stock item that comes on a 10’ roll and
is 1/2” thick.  This closed-cell sponge
tape worked perfectly on our metal
cans and was very easy to tear and
apply.  Cost:  $2.48 for 10 feet.  
That works out to 30 insulators for about 9 cents each.  We see no issues with this solution -- but, we would prefer a full 2” wide tape.
 
The disadvantage to the Stock Sponge Tape solution:
  1. •  Adhesive must be applied above 50 degrees F.
A few of our customers are operating in freezing temps and require an all-temp adhesive.
 
  1. •  The width is only 3/4” -- this could allow compression if they RFID tag touches the metal
The extra 1/2” on each side would allow someone to compress the 2” wide RFID tag and use the RFID tag to hold the foam against the metal -- lowering the .4” minimum air gap needed for full RFID range.
 
  1. •  Not pre-cut
You’d need to tear or cut each piece.  This can lead to waste if pieces are cut too long.  Short pieces shouldn’t be too concerning unless they are very short and allow the antenna to wrap and touch the metal.
 
If none of these disadvantages concern you, then consider the stock-foam solution.  We contacted the manufacturer of the tape directly and received a direct-sale price of $2.04 per unit of 4,000 units with lead time of about 7 business days.
 
We kept looking for alternatives and came across another ‘stock’ solution from FoamTapes.net (Lamatek).  They manufacture an open cell Ester tape that is 2” by 1/2” by 25’.  This seems ideal for our application.
 
Lamatek Semi-Stock Item
 
FoamTapes.Net manufactures a number of sponge tapes and also offers die-cut sheets of self-adhesive sponges.
 
While we don’t have final numbers and testing on these products, we think they will be the answer to an efficient peel-stick-ship™ solution.  
 
Disadvantages:
  1. •  50 Degree F or higher application temperature
These are good to -20F once applied but we really need something that will be good for application to 20F.
 
  1. •  Not die cut
Waste / excess is still possible or antenna overrun.
 
The price on the FoamTapes.net is rolls 30 @ $5.30 each.  Essentially, this is lower than the Wal-Mart solution and a full two inches wide!  Per unit cost about 8 cents.
 
 
The Ultimate Metal Mount
 
We hope that by next week we will have delivery time frames for a made-to-order item with the following properties:
  1.   4” Wide
  2.   Cut every 2” for easy, accurate peeling
  3.   Application temperature to -20 degrees F
  4.   < $.10 cents each for quantities above 50,000 and even lower above 100,000 units
  5.   Available on rolls or on sheets of 40 at 20”x16”
 
Keep an eye here -- we will be looking to consolidate an order for several large shippers to get the lowest possible pricing.  Please, send us an email if you can contribute to this initial order so we can get everyones cost as low as possible.  
 
Once we have the ‘formula’ -- we will stock these for smaller quantity shippers that need a simple peel-stick-ship™ solution.
 
Other thoughts:
What about 4”x1” RFID Tags?  
Smaller tags might lower the cost (less foam / less storage / less shipping cost) but it would also have less adhesive to grip the product and reduce the printable area making the human readable information unreadable.  Long term, we will pursue this as a measure to reduce costs.  Perhaps we can save 20% on foam material?  There is no cost difference for the RFID tag by selecting a 4”x1” product.
 
What about water?  Will the foam absorb water?
We tested this and found that water has a negligible, immeasurable effect on the tag.  This was tested with closed-cell foam -- we will repeat the test with open-cell foam which will absorb substantially more water.
 
* UPDATE: December 1:  We tested with Open-Cell.  Water has a significant impact on open cell foam as it absorbs the water.  However, this is only an issue if you plan to leave your containers ‘in the rain’.  Under normal situations, open cell is fine -- and cheaper.
 
One thing we did find:  Don’t use a paper tag if you think your product will be exposed to water.  This may seem obvious, but paper + water = kids science project.  Consider a polypropylene or polyester tag for chemical/water exposure applications.  We stock our poly tags as the ‘Traveler RFID Asset tag’ or we can custom order any size you need.    
 
-Carl
 
Metal Mount testing was performed using SimplyRFID Pro-Tags Travelers on 5-Gallon military grade canisters.  While the techniques described here may work for other RFID tags or metal types (55 Gallon drums, etc), you should perform testing to verify.  
 
SimplyRFID will test your products metal properties at no charge if you send a sample to us.
Sponges?
Friday, November 24, 2006
Image ©FoamTapes.Net
Image ©FoamTapes.Net