How to get a piece of cast iron sheet about 30cm x 30cm?

GervisLooper

They sell all sorts of sheet metal online like steel, copper, brass and aluminium yet cast iron seems missing.

All I can find is the rods to mould, which is no good to me.

I want to replace a glass stovetop since the glass stove keeps breaking I am thinking cast iron would not have such issues while having the same thermal expansion properties and not liable to crack. Very hard to find something though.

Thickness around 5mm or so ideally.

ThisIsWeird

Although cast expands less than mild steel, I don't think it's by much, and the steel is likely a safer overall bet?

How would it be secured in place?

Photo of this stove, please?

Section62

GervisLooper said:

They sell all sorts of sheet metal online like steel, copper, brass and aluminium yet cast iron seems missing.

All I can find is the rods to mould, which is no good to me.

I want to replace a glass stovetop since the glass stove keeps breaking I am thinking cast iron would not have such issues while having the same thermal expansion properties and not liable to crack. Very hard to find something though.

Thickness around 5mm or so ideally.

The clue is in the name....  'cast iron' is cast to form objects in their final form.  Other than as ingots to smelt, CI isn't sold as a 'raw' material to be worked on - not least because working cast iron is exceptionally difficult without the right tools and equipment.  The alternative is finding some scrap which suits the purpose without needing too much modification.

But making alterations to fuel-burning stoves isn't really a DIY project - getting it wrong can result in CO poisoning or death.

Mistral001

I am intrigued, as to the type of stove that has a 30X30cm glass top.  A photo would help as suggested, but failing that, a short description would suffice.

FreeBear

Put simply, you won't find cast iron sheet in the size you are looking for. I have a few bits of CI here, none of it less than 25mm thick (and yes, a few of them larger than 300x300mm). One source might be a CI griddle pan if you can find one big enough and have the tools to machine it.

Cast iron is relatively brittle and thin sections will crack if subjected to impacts. For a stove top, stainless steel might be a better choice.

teaselMay

I too can't picture what you're trying to do but as above I think you're looking for the wrong thing

outtatune

How are you managing to break your stovetop?

GervisLooper

FreeBear said:

Put simply, you won't find cast iron sheet in the size you are looking for. I have a few bits of CI here, none of it less than 25mm thick (and yes, a few of them larger than 300x300mm). One source might be a CI griddle pan if you can find one big enough and have the tools to machine it.

Cast iron is relatively brittle and thin sections will crack if subjected to impacts. For a stove top, stainless steel might be a better choice.

I tried mild steel to start. I think it was 4mm and it bent hideously out of shape causing diesel fumes to go all in the van.

I was only testing so was not a huge surprise and shut it off quickly. What was a surprise was just how fast the metal bent.

I looked up the thermal expansion properties here: https://www.engineeringtoolbox.com/thermal-expansion-metals-d_859.html

Stainless steel it says should actually be less tolerant then mild steel, the latter which was already a bust.

I don't get that because I have stainless steel pans which don't bend when cooking on the top so why would the mild steel bend so much when apparently it has less thermal expansion, according to that list, than stainless steel?

I am not fixed on cast iron and for the reasons stated above it makes sense why it is not suitable, unless I happened to find a piece already cut that fit the aperture.

Glass is a nuisance due to the chance of breakage and that is not a good combo when in a van often bouncing around on bumpy welsh single track roads. I don't think the bumps caused it in this case though, unless it was a cumulative weakening over time, as the hood is bungee strapped down so there is no lift to 'slap' the hood to the stovetop, like before. I learned that lesson on the first cracked top!

This time I think it was because of lack of contact from pan to stovetop from not cleaning the gunge off properly and so there were gaps causing the glass to over heat and crack. I can't say for sure but I am thinking that is the most likely scenario.

If I am unable to find an equivalent steel, which would not bend, looks like I will get another glass and try and take better care of cleaning the stovetop between uses.

GervisLooper

Mistral001 said:

I am intrigued, as to the type of stove that has a 30X30cm glass top.  A photo would help as suggested, but failing that, a short description would suffice.

https://www.jpparkingheater.com/product-fjh-18-1c-dz-n-jp-single-burner-diesel-rv-marine-stove

GervisLooper

Section62 said:

GervisLooper said:

They sell all sorts of sheet metal online like steel, copper, brass and aluminium yet cast iron seems missing.

All I can find is the rods to mould, which is no good to me.

I want to replace a glass stovetop since the glass stove keeps breaking I am thinking cast iron would not have such issues while having the same thermal expansion properties and not liable to crack. Very hard to find something though.

Thickness around 5mm or so ideally.

The clue is in the name....  'cast iron' is cast to form objects in their final form.  Other than as ingots to smelt, CI isn't sold as a 'raw' material to be worked on - not least because working cast iron is exceptionally difficult without the right tools and equipment.  The alternative is finding some scrap which suits the purpose without needing too much modification.

But making alterations to fuel-burning stoves isn't really a DIY project - getting it wrong can result in CO poisoning or death.

I have already swapped the stove glass out myself with no issues. It is not hard you just have to make sure to use lots of sealant to ensure the seal is intact again and there is always the co2 monitor to tell you if anything is awry. The problem is glass is prone to breaking which is why I would have liked to seek an equivalent make of more durable material but it seems rather unattainable for metal which would not bend.

FreeBear

GervisLooper said: Stainless steel it says should actually be less tolerant then mild steel, the latter which was already a bust.

I don't get that because I have stainless steel pans which don't bend when cooking on the top so why would the mild steel bend so much when apparently it has less thermal expansion, according to that list, than stainless steel?

A pan doesn't bend like a flat sheet would because of the shape. Pan bases are usually fairly thick, and the edges are constrained by the sides.

If you were to weld (or rivet) some stiffener strips to your flat sheet, that would go some way to reducing the distortion.