Badly-damaged lamp for repair.
First remove glaze from the broken edges to ensure a good urushi bond; sandpaper can also be used.
Then join pieces one by one using epoxy glue and support repair using masking tape. Quick-setting epoxy is usually sufficient but for a large heavy piece a slower-setting epoxy gives a stronger finish.
In this case there was still movement while glueing due to the size and weight of the lamp so masking tape was used as a lightly-adhering support bandage during the glueing process.
Putty was used to fill the gaps.. no need to check for leaks in this case!
First urushi coat in red then placed in moist box for 24h.
Second coat is in black to highlight any missing areas then placed in moist box again for 24h.
Third coat in red again then moist box briefly 10-30m.
Dust brass powder with brush.In this case I chose blue brass powder because the piece is predominantly blue.
Remove excess brass powder gently with brush or silk ball. Take care not to break this surface powder coat. Place in moist box for ½ hr then repeat removal of excess brass dust and start polishing gently at the same time. Repeat this stage 2 or 3 times more at 1hr/2hr intervals, replacing in moist box each time.
Finally after settling in a safe place for 1 week, repair can be washed gently using soapy cool water.