Dial indicator mount

thingiverse

I created this mount for the dial indicator to calibrate the bed of my Prusa Mk2.5. It's designed specifically for use with this indicator: https://www.amazon.com/gp/product/B07888LX1R/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1. The indicator attaches directly to the extruder, replacing both the part cooler fan and shroud (it utilizes the top mounting hole of the fan). I included standoffs for the screws so you can utilize the screws you removed earlier (the fan screw is longer, thus is the standoff). Two STL files are provided: a single-piece model and a three-piece version. The holes on the back are countersunk for the small screws that secure the indicator in place. This simplifies printing the back with the wider holes facing up, but requires printing standoffs separately if you choose to do so. If you can manage the overhangs, you may try printing it as a single piece. After printing is complete, use a thin drill bit to clean out the small holes (the tiny screws that hold the back are quite delicate and easy to strip their heads; don't use them to clean the plastic if they don't fit easily). If you opt for the three-piece version, you'll need to assemble it using glue. The shorter standoff goes to the long arm, look at the single-piece model for reference - I used basic superglue, there's no force on these joints, but alignment is required. Use an M3 screw or hex wrench to align the holes. After mounting the back, remove the fan and shroud and install the indicator. Take measurements above every mounting screw on the heatbed. Compare these values with those taken during cold bed and heated bed measurements. I found that while the values change, the differences remain nearly consistent. The highest point remains unchanged; every other mount will be shimmed up, so calculate the height differences. Now it's time to print washers to level the bed. To make installation easier, I added handles: the long one is for the central mount (hard to reach), and the short one is for the corners. You'll need to adjust the washer thickness first; either edit the STL or rescale them in your slicer. Set the layer height so that one or more layers add up to your desired thickness (the first layer doesn't have to be 0.2mm - you can do 0.15mm, which is about as thin as you can go). I printed mine from PETG. Thin washers may be difficult to remove from the bed without tearing them; use blue tape for better adhesion and easier removal. It gives good enough grip for one or two layers, and you can peel it off the bed then roll it under the washer. I initially expected an iterative process but found that there's no need: after installing all the washers, I achieved near-perfect leveling according to the indicator. Remember to rerun Z calibration and reset manual bed level corrections to zero.