Post up a pic. Depends where the pits are and how big. If the pits are down low, no big deal. If the pits are between the top of the cylinder and the exhaust port then you have to start thinking about longevity.
Thanks KR,
Once the pits appeared, I got 'experimental' with the cylinder, trying different grits of wet-dry paper, seeing what more acid would do, etc.
This was a first attempt, and I was originally expecting to replace the cylinder, so I am not that disappointed, but think that a more experienced hand might have saved it, so I am trying to learn from it.
The procedure was more tedious than I expected, and I think that 'the next time' I need to be more conservative and sparing with where I place the acid, rather than trying to remove all traces of aluminum and assuming that the plating will protect the rest of the cylinder. That is why I asked the "
When do you stop?" question.
I also found it hard to see into the cylinder, especially that area above the exhaust port.
I started with 600 grit wet-dry paper (note: US grits are different than European 'P' grades!) which was very slow. 220 was too rough, and quickly scratched the plating. Even some of my ScotchBrite pads scratched the plating (ScotchBrite comes in different grits - this might have been coarser than the kitchen/dishwashing pads). I think that the 320 to 400 grit wet-dry paper is probably the best compromise to leave you with a lightly honed surface.
I like Naturelover's idea of using a piece of hose as a sanding block, as my fingers got tired fast.
Philbert