There are three items that are required to be filled in when using the
calculator.

The first is the allowances for fabrication (etch factor). The second is the
pick and place accuracy. If you are unsure what number to actually use, you
may select the default for that component group as shown in the online
assumptions block.

Next you will have to indicate what your desire solder joint fillet sizes
are. These are for the toe, heel and side. These values usually come from
your manufacturing assemblers. However, you may again utilize the default
values for that specific component family as shown in the assumptions table
or in similar components within the family in the calculator.

You will be required to make adjustments so that the resulting land pattern
fits comfortably on an even grid increment. Make sure you consider which
joint provides the greatest strength to the connection and make your
adjustments so as not to violate that particular minimum joint requirement.
The other two joints are not as significant and therefore may go on the
negative side in relation to the lead size.

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