After having our uPrint SE Plus 3D printer down last week, I submitted am instructable for a dial indicator adaptor to fit on the “X:” way of the machine to tram the bed in to specification. (https://www.instructables.com/id/UPrint-SE-Table-Tram-Adaptor-Dial-Indicator-Mount/) While the adaptor worked very well for the “Y” axis, it just didn’t work well enough for the “X” axis so I retooled and looked for another way to easily mount a dial indicator on the printer head. The end result is this Instructable with a much simpler adapting plate. This style actually mounts on the print head instead of the “X” axis and worked really well. I had the bed trammed in under 10 minutes. I’m sure that I’m not the first to have to do this and surely won’t be the last so here’s an Instructable on how I accomplished this task.
Step 1: The Parts Layout
I reused some of the part geometry from the 1st Generation model, specifically the Indicator Mount tabs and the Indicator Mount Pads as seen in the middle of the parts layout. I adjusted the backing plate size so that it was big enough to straddle the print head and made two rectangular slots in the upper corners where the two mounting/locating legs will slide in. The mounting of the Indicator Holder is the same as the previous generation design and uses the four square holes bottom center of the Backing Plate (Left). The two Mounting Arms have holes in them as I originally though that I would pin the arms to the print head, but later decided that they were unnecessary.
Step 2: Gluing the Parts
The Indicator Mount Pads need to be glued to the Indicator Mount Tabs and then the completed Indicator Mount sub-assemblies are glued and mounted into the backer board. The mounting tabs for the Indicator Mount sub-assemblies should be flush mounted in reference to the back side of the Backer Plate. There should be about .187" of free clearance on the front side of the Backer Plate.
Step 3: The Mounting Arms
The two Mounting Arms will need the tips with the holes thinned a bit as they are a little too thick to fit in the mounting slots. The goal is to obtain a slight taper so that they slide in with a snug fit. I sanded from about the last 1/3 down to the tip with the tip getting the most material removal.
Step 4: The Mounting Arms
The Mounting Arms are slid into the two slots on each side of the Print Head where the clear plastic cover is mounted. I slid the two Mounting Arms into these slots and then applied glue to the Backer Plate Mounting Arm Slots and then slid the Backer Plate onto the arms until the plats sat snugly seated against the front of the Print Head. This resulted in the Mounting Arms being at a slight angle less than 90 where they intersect the Backer Plate. The glue was allowed to set overnight in this position. And then removed the next morning so that the Dial Indicator could be mounted as shown in the picture. Note that the Mounting Arms protrude through the face of the Backer Plate.
Step 5: Final Assembly
Once the Indicator is mounted, slide the Mounting Arms back into the slots on each side of the Print Head so that the Backer Plate sits snugly to the face of the Print Head. Then take a rubber band and bind the Backer Plate to the Print Head. This allowed for a snug enough fit that indicating the table was easy. Now all that is needed to indicate the table is to raise and lock the table so that the indicator is positively engaged. Zero the indicator and then move the print head by hand to the four corners of the print table, being careful to avoid any slots. Adjust the table so that each corner reads the same on the indicator. In my case there was about .002" of variance through the middle of the table, but it did not cause any issues with calibrating. I'm told that the magical threshold for calibrating is .016".
Hope this is helpful!
Doc D in the Dungeon