If you are new to RMHs, you may have read how there is no ash...
Not quite true, it is true that if built correctly, there is little to no ash downstream.
But there is plenty of ash before the riser, in both J-Tube and Batchbox designs.
Starting as loose ash, it will quickly bake into an ash cake several inches thick.
I often do a quick cleanout by breaking chunks of ash cake into handheld pieces (be careful, as ash can hide hot coals for a long time)
I have a nice metal can to haul ashes in.
I built a strong short-handle scoop to remove the majority, and as long as there are no coals, I use a small brush or my hand to clean around the secondary air stub and riser port.
I clean the two outdoor Dragons as often as every two weeks, up to six weeks.
If it is frozen outside, all ash is used on the gravel driveway and trails. When it's muddy, I toss it over the bank.
My new Shorty Core also produces a fair amount of ash, but as it is in our home it only gets two fires a day or less.
Cleaning Shorty is a casual affair when you have the time,