Punching hemispheres with dome punches and blockA dome block is a device with usually hemispheral dies in it, made of hardened steel (sometimes of brass or even hardwood) intended for making hemispheral shapes from sheet metal. A dome punch is a globular punch to force sheet metal into a globular shape by giving it a hammer blow on the metal sheet disc which is laid in a dome block die. I use sheet metal of 0.25mm thick in a disk shaped 22mm diameter to get a 16mm diameter sphere. I just cut this out of sheet metal. Punching doms of silver or other malleable metal requires some experience. The problem is that the edges of the dome can be damaged when putting into a smaller die of the punch block.Fortunately, all errors made by damaging is not a waste of material, as I just remelt them, pour it into a small slab which I rollagain into sheet. | |
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Drawing circles on silver sheet to cut out | 
The drawn circles | 
Punching the disk for the first time |
Annealing after two punches | 
Two domes which are damaged lying on the dome block | 
The two copper and two silver domes below are correct, the upper row is damaged within the hemisphere |
Sawing away the warps and dents | 
Sawing away the warps and dents | 
File the domes to get them flat to fit on each other |
Round completely before soldering | 
Both halves should be round shaped and be filed flat | 
Before soldering |
After soldering | 
After soldering: a little solder error: hemispheres not fully aligned. |
