- Joined
- Apr 28, 2016
- Messages
- 86
I have a Langmuir MR-1, which is a gantry type "mill", which means there are two independent Y-axis ball screws. Mis-calibration not only produces parallelogramed parts (I invited a new verb?) but also racks the gantry and causes the Y-axis motors to miss steps. The calibration procedure is to sweep / align a square reference to the X-axis and then to sweep the square surface and turn only one of the Y-axis ball screws until an indicator is sweeping true. The assembly guide procedure is to turn one of the ball screws with pliers and rag... I'm not a fan of that so I unplug of the Y-ais stepper motors instead.
I have used a subtool "value line" 2"x3"x4" block for calibration but I would like a longer reference surface to sweep. I've been looking at new/used angle squares on ebay but most of these are too thick to fit under the MR-1's ~6" gantry clearance and I don't have the means to check if a used angle block is true. I do have a surface plate... so in theory I could check that a master square is running true.
All the reviews I've seen of the input granite tri/master squares are in the horrifying category. I emailed standridge granite this morning asking if they had anything "economical" that wasn't on their standard price list that would give me 6-12" surfaces true to 0.001" per 6". They offered a grade B 8"x8"x4" tri square for $485 + $67 freight. Is this a reasonable solution for the cost? Is it overkill? Is there a better calibration reference I should be considering?
I have used a subtool "value line" 2"x3"x4" block for calibration but I would like a longer reference surface to sweep. I've been looking at new/used angle squares on ebay but most of these are too thick to fit under the MR-1's ~6" gantry clearance and I don't have the means to check if a used angle block is true. I do have a surface plate... so in theory I could check that a master square is running true.
All the reviews I've seen of the input granite tri/master squares are in the horrifying category. I emailed standridge granite this morning asking if they had anything "economical" that wasn't on their standard price list that would give me 6-12" surfaces true to 0.001" per 6". They offered a grade B 8"x8"x4" tri square for $485 + $67 freight. Is this a reasonable solution for the cost? Is it overkill? Is there a better calibration reference I should be considering?