It has been a while since i posted my Tinker Rule which i made during college days. I received a few requests for the ready to etch pdf which helped me gauge if this seemed to be useful to people. The response was somewhat positive and so, i decided to put in some extra effort and make it handy, portable and manufacturable !
My initial scale was big and not handy, So, this one should be small and compact and must not miss a single feature from its ancestor. This one has :
- 0.1 inch grid to quickly prototype/resolve parts for perf-boarding or part creation
- A collection of footprints and holes to quickly compare parts
- A small pad with a sand paper to rust off those berg strips/resistor ends that just wont solder located ergonomically at the end to allow easy motion
- A key chain form factor
- A LED Tester
- A continuity tester compatible with most common 4.5mm banana plug type probes and alternatively alligator clips too
- A reference section for common equations,scales and track widths.
- 0.1 inch scale at right angles
- 1 mm resolution scale at right angles
I made an initial to-scale mockup to verify the parts and ergonomics.
Then redesigned the board iteratively in KiCAD. The size was a bit higher to utilise the low volume PCB fabs from China.This presented an opportunity to search and try some local manufacturers and add a month to the project. Most of them unfortunately gave disappointing replies to mails for low volume production.
Aghasted, I started street searching for PCB manufacturers here in Pune. Fortunately, I live near an Industrial Area and Just Dial churned out a humble number of results. I visited a few of them and finalised one based on cost, quality and turn around time. But had to re-design it yet again to match the tolerances.
Made In India 😀
Here is what i managed to make :
The 5mm hole doubles up as a key-chain ring.
Use normal multimeter probes with the Maker’s Rule for continuity testing. My multimeter meter has a habit of dying down when i need it the most to check continuity of newly etched PCB. Here i use a 0805 LED for the output.