I mean... the ones that are any good are about twice that price. Ex: I personally prefer CUI encoders: https://www.cuidevices.com/amt-modular-encoders https://

I mean... the ones that are any good are about twice that price. Ex: I personally prefer CUI encoders: https://www.cuidevices.com/amt-modular-encoders https://www.cuidevices.com/amt-modular-encoders and they run about $50 each (with bulk ordering able to get you closer to $40). But I think you're not really considering the problem space from all the appropriate angles. Ex: The main reasons you avoid putting encoders on a 3d printer... 1. Weight - Hands down the biggest in most cases (excluding CoreXY setups). Each of those CUI encoders is about 16 grams. Total moving weight matters a lot in printer design. Go too high and you have to bulk up every other part of the machine to account for it and reduce shake/wobble and ensure you can maintain the correct accel. Or you have to print much slower, which makes the machine less capable (and valuable). It also adds wear and tear and increases friction. 2. Safety - They aren't worth very much in terms of safety. You can detect a lot of bad things by just setting sane current limits in your motor controllers. Combined with the thermal runaway protection available in most firmware... that covers most of the same things you can detect with encoders. 3. Value - Steppers are already incredibly precise. There is limited value in adding the extra encoder feedback into the system. Most of the cases where it matters are already detectable (and without any need for OpenCV...). So encoders are nifty - but this isn't really the best case for using them. No big win and lots of downsides (not the least of which is the extra $150 for adding them - which is 50% of the total cost of my first printer).