I have a partial reel of tape with components. The label says 2500 pieces. Counting the outermost layer (60 pieces) and multiplying it with the number of turns (15) gives 900 pieces. But the inner turns will have fewer components.
The spool has an indicator like a ruler which goes from 1 to 11. The belt ends at ~3.5. But I have no idea how full it may have been originally.
As a hobbyist I don't have a counting machine or similar. Is there a known approach to get a better estimate except counting manually? If you do math, please mention the formula, since I have many other reels like this with different number of turns, diameters etc.
Here’s how my reel(s) look like:
The component is ST72F324BK6T3.