Black Epoxy Steel Varroa Mesh or not

[666bees]

Is is worth using Black Epoxy Steel Varroa Mesh instead of the ordinary varroa mesh? Does oxalic acid attack the ordinary mesh?

 

[oliver90owner]

Stainless steel is an alternative and likely competitive with the coated stuff. I used the galvanised expanded metal squares (from the likes of Th*rne) as they imparted rigidity and accurate shape to what can be lighter-weight wooden parts, but have just made a batch of floors with S/S mesh.

Galvanised wire screens are also available at very competitive rates . I have made travel screens with this, but would not be bothered if it were in my floors. They are all available from the mesh company at competitive rates. I avoided the epoxy as it is not flame proof (as well as not being available at the time).

No connection with the supplier - just a satisfied customer.

Oxalic acid is not regarded as one of the 'strong' acids and is used for cleaning brasses and similar. Not sure of the effect on plain steel, but not much worse than rusting away slowly. Galvanised may be more resistant but not tested. You are only talking here of the same strength as vinegar, for instance, if trickling.

Regards, RAB

 

[Rosti]

Oxalic acid is not regarded as one of the 'strong' acids and is used for cleaning brasses and similar.

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).

 

[oliver90owner]

Yes Rosti,

Didn't even titrate oxalic acid with strong alkali and an end point of around pH8, probably using methyl orange(?) or thymol blue as indicator as would be standard with a weak acid.

Our usual method was titration with pot permanganate under hot, and probably strongly acidic, conditions. Can't remember precisely how, as a long time ago - at least thirty years!

Perhaps I should get out the old gravimetric/volumetric analsis books and have a recap.

Regards, RAB

 

[Skyhook]

Is is worth using Black Epoxy Steel Varroa Mesh instead of the ordinary varroa mesh? Does oxalic acid attack the ordinary mesh?

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.

 

[Repwoc]

a higher pH at like-for-like H+ concentration

The way I remember it pH = -log10 [H+], ie pH depends on H+ concentration and nothing else.

Oxalic is a stronger acid than acetic (dibasic, and higher dissociation) but still weak compared with mineral acids. A tiny amount once a year isn't going to do much harm to a mesh floor.

 

[oliver90owner]

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.

Regards, RAB

 

[madasafish]

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.

Regards, RAB

I recommend heatproof aluminium paint for car exhausts..

 

[Finman]

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.

Regards, RAB

Galvanized zink and acid is not a good combination. Depends on ganvanization how fast the zink erodes away.

Stainless steel or should it be acid tolerant steinless steel - awfully expencive.

Acid + aluminium = poison

What is problem with normal steel mesh and then you renew it when it is out.

 

[johna]

No need to blowlamp mesh-just use washing soda and rinse well after with water.Hot air guns work well also and willonly scorch if used to excess.

 

[Bee-Key-Pur]

Just a thought, but all the mesh floors I have and they are all made by different people, the mesh either slides in a glove cut in the floor and held in place with a few drawing pins, or the whole piece of mesh is held in with drawing pins.
Surely, if you need to scorch the hive, you could just remove the mesh in a matter of seconds !!!

 

[Rosti]

The way I remember it pH = -log10 [H+], ie pH depends on H+ concentration and nothing else.

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 use

 

[Hivemaker.]

4-8% AKA vinegar is stronger than a 3.2% oxalic sugar solution at point of use
But which would you prefer to pour on your fish and chips...lol.