5 Aluminum discs on the Espresso Maker Base?

[Uncle Gizmo]

This is driving me nuts!

I’ve got a stovetop espresso maker (by Kirkton House) with 5 lighter aluminum discs on the base. Any idea what these are for? Could they be a safety feature or part of the construction process?

I have been around the houses interrogating ChatGPT, trying to get it to come up with a sensible answer but it has no idea, just like me!

So if you lot here can answer this question, then that means we have a collective intelligence greater than ChatGPT!

#EspressoMaker #CoffeeLovers #Kitchenware

 

[AccessBlaster]

Could they be a heat sink?

 

[Pat Hartman]

Is it the same concept as a double boiler? That isolates the milk or other delicate liquid from the heat source to minimize the scorching that could happen if the inner pan was put directly onto the heat source.

 

[Uncle Gizmo]

Could they be a heat sink?

I ruled that out because the whole thing is made of aluminium. Or should I say aluminum !

So I can't see any benefit from adding an extra piece of aluminum to conduct the heat?

 

[Uncle Gizmo]

Is it the same concept as a double boiler?

It's a single skin piece.

 

[Uncle Gizmo]

Both the inside and outside of that surface have been lathed flat as can be seen from the lathe cutting tool marks... (Possibly not visible in the picture)

 

[Pat Hartman]

I have very expensive cookware that has multiple layers, is that what you are talking about? The layers are actually different materials and are used to ensure even heating of the pan. The pans have been in daily use since 1965 and although the handles look a little tired, the metal is as good as new even after 60 years of use.

 

[Darrell]

I think these are first sand cast, so they are probably the sprue marks remaining after then machine flat in a lathe.

 

[The_Doc_Man]

I like Darrell's answer but there COULD be another facet of this. Strictly hypothetical, but it IS based on how ebullition works.

If those little disks are in fact slightly different alloys than the rest of pot, then they are boiling surfaces built into the pot so that steam bubbles will form on those disks first. Aluminum has among the highest heat conductivities of all elemental metals. If the rest of the pot is aluminum but of a different thickness OR a different alloy composiition, that difference COULD be just so that boiling occurs at those points.

It would be a relatively easy test to just put water in the pot and leave the lid off. You might have to wait a while (watched pots never biol, remember...) but you should be able to see bubbles forming on those disks first. There is ALSO the possibility that they are NOT aluminum, but another alloy entirely, one with iron in it, and they have those disks for times when they are on an induction surface cook top.

 

[AccessBlaster]

I would think a casting that small would have only one sprue, but maybe commercial pours might be different.

 

[Uncle Gizmo]

I did a Google search for "how it's made - stove top espresso maker"

And found this YouTube video,...

Although a very interesting video, it does not discuss the disks. In fact in the video one clip shows the bottom of this original version of the coffee maker and it doesn't appear to have the aluminium discs in the bottom. See time index 4 minutes 20 seconds...