BlasToolPro is a calculator/converter with more than 100 formulas to provide solutions for such topics as. 1. Blast Pattern Design. 1. 1. Bench Height. 1. 2. Hole Diameter. 1. 3. Burden. 1. 4. Spacing. 1. 5. Sub-Drill Depth. 1. 6. Top Stemming. 1. 7. Deck Stemming. 1. 8. Base Charge Length. 2. Delay Timing. 2. 1. Hole-to-Hole delays. 2. 2. Row-to-Row delays. 2.