Nice round eyelets are not want if you are using double sided PCBs. See Keith post below and read mine again.
Repeating my previous post:
Note: For joining top to bottom layers as is normally done, you do not want perfect little tubular eyelets. You should use eyelets that are formed from a strip and rolled into the eyelet shape. It will have a desirable vertical slit in it.
I know it sounds backwards but the reasons are very valid.
Many decades ago Motorola used eyelets on PCBs instead of through hole plating. Originally nice round eyelets were used and there were a lot of field failures. The solder properly solders the bottom section to the bottom runner, it wicks up through the eyelet and solders the component lead but there is no capillary action to draw the solder over the eyelet’s top edge onto the top runner so it only makes mechanical contact. The eyelets with a vertical slit avoids that problem.
Bertho
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Homebrew_PCBs@yahoogroups.comSubject: RE: [Homebrew_PCBs] brass tube vias
When I worked in an electronics plant ,they had a hollow rivet they used for this. I saw many boards come back in for service where the rivet was no longer soldered to the pad. They used these where connectors were put in the board to strengthen it. I would at the very least wash the brass tubes in a mild acid to clean them and rinse well before using . lemon juice may work as I have seen it used for flux in a wave solder machine.