Wednesday, October 14, 2009
Copper Plating Wire Glue
- The resistor shown was roughly 10mm long and its resistance came to 2kΩ, so it looks like wire glue has a sufficiently high resistance to make useful resistors. Unsurprisingly the copper plated sections had a resistance of 0Ω, and could be soldered to very easily (unlike the circuit produced using the solder extruder).
- The track needs to be connected to the power supply both before and after each "resistor". Otherwise, the track is only plated up to the buried section of wire glue.
- The entire copper plating process is much more even if a small amount of sulphuric acid (car battery acid) is added to the copper plating solution.
- We need to be able to make several sections of track per PCB, and it is going to be a bit of pain to connect each section to the power supply. As an alternative, I included a small "bridge" whereby the track is only supported by a small section of ABS, such that it is easy to snap out afterwards to create two independent tracks. It seemed to work (see pic below), although its not as clean as I would like, but a support material extruder would help with this enormously.
- It is very important to leave the wire glue to dry sufficiently (at least a few hours). I did make a few attempts where the glue was not completely cured, and virtually no plating was achieved, even when left overnight.
- I did try producing the PCB using PLA on Darwin - it seems our infill settings result in the structure being porous. Of course, this could be easily remedied by altering the settings. However, if we change the infill such that some parts of the structure are porous and some aren't, we can allow the copper sulphate solution to seep into the structure; allowing track to be plated that is contained within plastic. This may prove very useful later on if we ever get around to doing things in 3D.
Labels: circuit, copper plating, wire glue
Wednesday, June 06, 2007
Very fine RepRap nozzles
Stick a standard nozzle with an 0.5mm hole on the end of a piece of silicone tube. Then flow copper sulphate solution through it and connect it up to copper-plate itself from a lump of Cu in the top bath (see the pic). The copper will plate on the inside of the hole closing it up. The thing has beautiful negative feedback, in that - if an area starts to close up too fast - the plating rate drops just at that location.
You can tell how the diameter is reducing by watching the flow out of the end slowing down. A few experiments would quickly establish how far up the side of the receiving vessel the level would rise in 30 seconds (owe) for a given diameter. Just time it, and turn off the electricity when you get there...
For best results it needs a constant-current source so you get a precise plating rate. You stuff the silicone tube right into the nozzle to prevent the threads being plated too.
Brilliant!
Friday, October 10, 2025
The Ancient Eastern Art Of Bulshito - "Stainless Steel Part 2"
Yep, stung again by an Amazon supplier. Advertised as 0.3mm Stainless Steel Wire. Absolutely not, as you can see. Some plated copper muck:
So three spools of that can go in the bin. My first clue was that it started copper-plating the spoon, er, cathode in my electrolysis setup:
FYI I was using 1% nitric acid rather than my usual salt water. I intended to see if that would stop the production of cloudy iron hydroxide so I could tell when the end fell off the etched probe more easily. Turns out I need to try a different batch of wire, huh?
Friday, March 22, 2024
Contacts unreliable but X and Z moving in sync
My idea of using electrical probing to find a conductive surface doesn't work. The probe bends visibly before my conductivity meter beeps. But using the small USB microscope to observe contact worked OK. Any electrical experts out there feel free to suggest solutions that don't involve wetting the contacts with mercury or gold-plating everything.
So I have distance indicators on the big microscope stage. I used that to measure how far the probe moved on the Z axis when the control panel moved the mechanism by a theoretical 2mm. It moved 1.39mm +/- 0.01mm. Then I did the same with the X axis, which tries out all the trigonometry code. It moved 1.4mm +/- 0.05mm. Amazingly, actual movement coincides on both axes! If I set the GRBL steps/mm scaling right, we should be nearly there.
One problem clear in the microscope is that the probe wobbles in the XY plane when moved in the Z plane by +/- 0.05mm approx. I don't know if this is inherent to the delta stage design, or if I've stuffed something up. It might be due to the huge offset probe arm. We shall see.
