3D Printed Resistor Checker
In this project I will show you how to make a resistor checker stand for your ohmmeter. It helps for those that don't know the color code or for those older, like me, who's eyes can't read the resistors very easy. This design is small so it can fit on most 3D printers and uses parts you probably already have in your workshop.
Watch the Video
This video shows you all the steps including how I modified a 3D print design from thingiverse.com.
Print the 3D File
Download the 3D .stl file from Thingiverse.com and print it on your 3D Printer. I used the following settings:
0.3 Layer Height
50% fill
ABS @220c
No Supports
You can use PLA or PETG instead. Either will work fine.
Create Resistor Test Terminals
I used a 14 gauge household wire to make the connection inserts for the resistors. I separated the wires into a single white and single black wire. Then stripped off about 2 inches of insulation and then hammered the end on a flat surface to create a flattened end. I did this for both wires.
Create V Cuts
I used a sheet metal press to cut the ends of the wires straight and the notched a V in them. You can do this with a file as well. The V is where the resistor will sit and make a connection.
Insert Wire
Insert the wire into the holes within the V portion of the 3D print. There is a whole in each V for the wire.
Heat and Install
Heat the wire with a lighter or small torch until its hot and then pull it from the bottom until the V in the wire lines up with the V in the 3D print. (I pulled it through from the bottom with a vice grip so I wouldn't burn my hand).
Install Second Insert
Install the second wire the same way and they should look at about the same height when installed.
Connectors
Insert connectors in the front of the print. The holes are 6.5mm so look for a connector with that outside diameter. These from Amazon.com should work but you can find lots of similar parts.
Solder Wire to Connector
Cut the wires and bend them to line up with the connectors. Then solder the connectors to the wire.
Connect Ohmmeter
Connect your ohmmeter to the stand and set the meter to resistance. My meter has an auto-range feature so you may have to guess on the range to set it to if you don't have that.
Test a Resistor
Drop a resistor in the V slots and let it touch the metal inserts on both sides. Give the meter a few seconds to settle out and then read the resistance. On smaller 1/8 watt resistors you may have to press down a little on the resistor to make a good connection. Make sure you touch the plastic case not the leads. Touching the leads could throw off the reading.
Success
You just created a handy tool for your electronics workbench. You can use this to test polarity of diodes as well if you set the meter to diode mode. You can connect power through a resistor to the connectors to make this an LED tester. It's a very handy print.
Check out some of my other 3D printer projects at FilamentFriday.com.