Galvanized Metal Block Off plate - Dangerous?

[holyoilbillbatman]

Hi all,
I am going to make my block off plate per the instructions in the article. However the article calls for using galvanized metal; I thought I recall someone mentioning recently (I believe on this board, but I could be mistaken) that when galvanized metal is exposed to high heat that it can give off dangerous fumes? Is there truth to that?
Also, I have just purchased High Temp fiberglass insulation (1000 degrees)... do you guys line the top of the block off plate with that as well?
Thanks!

 

[Hogwildz]

You'll be fine with the galvanized block off plate. If the insulation is truly 1000 degree, I suppose you will be ok.

 

[drizler]

The damage caused by fumes from galvanized metal or or Zinc Fever as they call it among other names is highly over rated. If you really get a lot of it at once it will make you a bit sick but its only temporary. Of course they are talking about welding where your kisser is right in the fumes coming off the object. Most welders just put a fan behind themselves and are fine. I can't see how anyone could have a problem from a plate up inside a chimney really. Since you are making your own you will find a piece of steel purchased at a scrap yard WAYYYYY cheaper than buying something at Lowes or Tractor Supply ect. You probably will find a big honkin piece of regular mild steel plate will hold up a lot longer than galvanized as long as you have the goodies to cut it.

 

[webbie]

The plate will not get hot enough to burn off the galv anyway.......I see virtually no danger in this.

I would be another thing to use galv stove pipe and then burn a stove hot - with your nose right above the pipe while the zinc was burning off.

 

[holyoilbillbatman]

Thanks for the info Guys!

 

[Elderthewelder]

The damage caused by fumes from galvanized metal or or Zinc Fever as they call it among other names is highly over rated. If you really get a lot of it at once it will make you a bit sick but its only temporary. Of course they are talking about welding where your kisser is right in the fumes coming off the object. Most welders just put a fan behind themselves and are fine.

I would not go as far as saying the dangers are over rated, There are many documented cases of severe health issue's and death caused by welding galvanized ( zinc poisioning)

people these day's are just more educated on the subject and use proper PPE ( respirator, fume extractors to name a couple) when welding any plated metal,

Puttin a fan behind you is not going to get it, especially if you are doing any type of gas shielding welding (mig,tig,dual shield) as the fan will just blow your gas coverage away, need to use a fume extractor posistioned either above or in front of your work, not behind

But to get back on subject , I would not think a galvanized block of plate would be a issue, but if I had the choice I would go with unplated steel