What is a via?
A via is an electrical connection between two layers of the board. In the Maker-E we use rivets to achieve this connection, and we can go from the top layer to the bottom. When making professional boards of more than two layers, you can make a connection between two layers that are not the top and bottom. This is called a buried or blind via. Because of the nature of vias, they can cause difficulties with high frequency connections. When making boards for RF purposes, it is advisable to minimize the amount of vias used, and to only use vias for low frequency purposes.
What is a rivet?
A rivet, pictured below, is a small copper sleeve that is inserted into the board through a properly sized hole. After the rivet is placed in the hole, the rivet is then crimped so that it makes an electrical connection with the pad on the top of the board, and the bottom of the board. While these rivets usually work on their own, we still recommend soldering the rivets after you insert them.
When do I need a rivet?
You need a rivet any time you use a via. In order to do this, set the hole size in ultiboard to 1.5mm.
The other time you need to use a rivet is when you have a through hole part with a pin where the connecting trace is located on the top copper layer. This is because, unlike surface mount parts, through hole parts are soldered on the bottom of the board. The problem occurs when you connect a trace on the top of the board to the pin of the through hole part. This will not work! There is no electrical connection between the trace on top of the board and the solder connection on the bottom of the board. (This is only true of boards made in the Maker-E. Professional boards do not have this issue.) Please see the image below for a closer examination of this issue. You will need to click the image to view a larger version. When using a rivet in this manner, it is called a Plated Through Hole(PTH)
How do I use a rivet?
To learn how to use a rivet, please see the rivet press guide on Dozuki.
I can't fit two rivets in my design because I get a warning about parts being two close together.
The warning indicates that there is a violation of the clearance around the pads associated with your part. As long as the pads (holes) have a pitch (spacing) of 2.54 mm (0.1") you can still use rivets. However, you should decrease the pad diameter from 2.5 mm to 2.4 mm. Maintain the same hole diameter of 1.5 mm.
Alternatively, you can add a via close to the part to drop the trace to the bottom of the board.
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