When the time comes to harvest honey from a hive, a beekeeper needs to decide how to get the bees out of the supers. Two popular methods are:
One of the most useful, info-packed books that I've read about beekeeping is Beekeeping for Dummies by Howland Blackiston. In the chapter on honey-harvesting, he says the fume board is his favorite method because it's "fast and highly effective" and that working out the timing for an escape board is impractical for a weekend beekeeper.
I've found exactly the opposite. My escape board has worked great and my fume board has been mediocre.
I've tried to use a fume board several times. I've experimented with different amounts of repellent. I've attempted to heat the board up in the sun first so that it makes the fumes stronger. But the results were always poor. The bees were mostly driven down out of the top-most super but many bees would remain in the lower box. Luckily, the bees weren't too rowdy and I could brush them out off of the frames.
I didn't want to have to spend this much time brushing off bees, so I purchased an escape board and it has worked out great. I put the board on at around 4pm. Then the next day I take off the supers at 11am. During my first harvest this year, this method was 100% successful—there were zero bees remaining. Other times only a few stragglers were left behind. Maybe it's the cooler September nighttime temperatures in Wisconsin that force the bees down into the hive to stay warm with the rest of the colony, but this method consistently gets them out.
Keep on keeping on.