How to make hourglasses?

How to make a custom hourglass? what devices&tools you may need? how can we get the countdown we want? how will you control the precision of the countdown? if you are a fan of antique ancient sand hourglass,you may want to know the details,here what i am gonna write will lead you to the first perspective of original manufacturer.

Here are pictures that may help you understand how are each steps running and finished!

First all of,let's see the general processing steps of how a custom hourglass is made:

Yes,these are Major steps,but you may still have many questions in your head,how's the details of each steps,take it easy,let's explain one by one:

Step#01:  warm the glass pipe up on the fire torch

Step#02: Stretching and extending automatically after heated

Here is what you will get:

Step#03: Forming the middle part of hourglass and drilling the sand leak hole

and Here is what you will get:

Step#04: Mouth blown to get the hourglass bulb in graphite ingot mold

Here is what you will get:

Step#05: Sealing one side,make it ready to filling in sand

See,you are quite close to finishing a hourglass

Step#06: Filling in Sand

Step#07: Time counting and correcting(Both sides needed)

Step#08: Seal the open side for filling in sand,and finally you get a finished hourglass

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