Maintenance - Obs Working Session

Time/Date

20230316T2100-2300

People

Onkar, Natalie, Matt

Spaces Occupied

433C, dome

Goals

1. Systems check - identify whats wrong

2. West mirror door displaced, did not nest properly

3. pointing is off, dfmtcs zenith and ts6 zenith disagree

Log

• onkar had a gut feeling things were wrong, went to check

  • was right, west mirror door didn't stow correctly

  • pointing was also off but whatever can fix that at next observing session

• west mirror door

  • onkar attempted to open mirror door via dfmtcs software

    • hears click, nothing happened

  • goes up to dome to check whats happening

  • mirror doors not moving

  • touched motors

    • very hot

  • ran down to control room and clicked "close mirrors"

    • another click

    • motors no longer hot to the touch

  • onkar conducted hammer time on west

    • hammered out bottom pin of the west piston to free the mirror door

    • taped the door to hold it open

    • unplugged west motor

  • opened mirror doors

  • undid tape on west door, lowered it closed, repinned piston to motor, motor plugged back in

  • closed mirror doors

    • north and south doors edges got caught on edge of east trying to close

    • solved this by smacking east really hard with percussive maintenance 

    • all mirror doors nest properly

  • opened mirror doors

    • everything opened all the way except west which was at 45 degrees

    • felt west motor, was vibrating

    • physically pulled on door to open it all the way

    • this probably means there's something wrong with the motor, piston, or both

  • closed mirror doors

    • west did not nest correctly, back to square one

    • UGH

    • unplugged west motor

    • tools readily available to conduct hammer time again

    • left it at this

• conclusion

  • DONT CLOSE THE MIRROR DOORS WHILE WERE NOT AT ZENITH

  • it was also observed that the motor will keep running until the limit switch is activated, but limit switch will not activate if doors are not nested properly, therefore the west motor was most likely running this entire time since last obs session until I checked it today - onkar

ToDo

1. ( nonessential) fix pointing next observing session

2. thoroughly check west motor to see if its burnt out

3. thoroughly check west piston assembly for stripped gears and broken parts

4. retest west motor piston assembly after step 2 and 3 are done

Notes

• scope is not at this time able to observe until the action items in "ToDo"

• it should be clear who is responsible in shutdown/closing procedures, IMO should only be an observatory expert/staff

Weather

- cleardarksky: 20-40% coverage, poor seeing
- NOAA: 50-80% coverage
- wunderground: 35-80% coverage
confidence in reporting: 4/5

Data

Normal place, synced to Google Drive