Quite obviously, we would like you to rely on SPI for your custom coated grid needs. However, if we can't do that, we hope you will rely on SPI for your coating resins, indeed, if not all of your microscopy laboratory needs! But if you have decided to do your own grid coating, then make sure you become familiar with some tips from the SPI grid coating experts!
A few words about contaminants:
We are often times asked about the presence or absence of contaminants such as the alkali elements and Si. In the production of the SPI coated grids we take all possible precautions to prevent such contaminants from ending up on the grids. From time to time we conduct analyses on new grids in our own STEM looking for the presence of any such elements. And almost never do we ever detect anything. And when we do, we take steps to purge those contaminants from our process. But we do not guarantee these grids to have that kind of purity. In order to provide that kind of guarantee, we would have to do extensive analyses on each and every batch and we believe that the increased cost would not justify the incremental benefit. If you have some particular need along these lines, just let us know and let us respond with suggestions on how we could meet your specifications but yet for a reasonable price.
Listed below are the main types of grid patterns requested. However we can coat virtually any grid pattern (well there are some grids that can't be coated) so be sure to ask if you don't see what you want:
Just remember that we at SPI can coat just about anything. We have a unique grid coating capability and if you don't see exactly what you want, then send us a message and let us know what you need. As a rough rule of thumb, the lower mesh are the grids (below 150 mesh) the higher the cost because they tend to take more time because they are more difficult to coat. The coating of grids made from etched metal foils a still higher coating cost because they are just more difficult to prepare coated. You can be sure that whenever you are quoted a "surcharge" for the cost associated with the grid coating, it is based on a direct extrapolation for the additional time it takes to coat that kind of grid.
Just remember that the biggest problem an SPI customer faces, when presented with so many alternatives, is to decide which of the various support film possibilities is the optimum for their particular task at hand.
Final note on packaging:
All SPI Custom Coated Grids, including the Allred™ substrates, when possible, are shipped in an SPI Slide-A-Grid grid storage box. Since sometimes, after coating, it is not always that obvious which side is coated and which is uncoated, we have adopted the following standard conventions and they will be used unless specifically instructed otherwise:
* For Formvar or carbon coated Formvar filmed grids: The coating is always on the shinny side of the grid. * For carbon coated grids, the carbon coating is always applied to the dull side of the grid and when loaded into the Slide-A-Grid grid storage box, the carbon coated side of the grids always face the center of the box. * For SiO and lacey grids of any type, the filmed coating is always on the dull side.