I agree with RAB, not an issue for either frequency of use or indeed composition - at 3.2% in use it is both weaker than standard table vinegar (primarily acetic) and has a higher pH at like-for-like H+ concentration (buffering effect of the syrup).Oxalic acid is not regarded as one of the 'strong' acids and is used for cleaning brasses and similar.
Worth bearing in mind that the black wont stand a blowlamp if you want to flame the floor between hives- but then neither will galv, stainless is the only thing that will.Is is worth using Black Epoxy Steel Varroa Mesh instead of the ordinary varroa mesh? Does oxalic acid attack the ordinary mesh?
The way I remember it pH = -log10 [H+], ie pH depends on H+ concentration and nothing else.a higher pH at like-for-like H+ concentration
Galvanized zink and acid is not a good combination. Depends on ganvanization how fast the zink erodes away.Galvanised should be OK as long as the torching is not overdone. Certainly taking it to red heat is a sure recipe for removal of the protective layer.
In standard solution yes, but not when you have it with a carbohydrate that is mopping all those little H's up before they even get a chance to do their stuff, so the 'nothing else' doesn't apply in this case. Oxalic is slightly stronger than acetic LfL true, but my comparison was with a table vinegar containing acetic typically 4-8% AKA vinegar is stronger than a 3.2% oxalic sugar solution at point of useThe way I remember it pH = -log10 [H+], ie pH depends on H+ concentration and nothing else.