|
|
|
Disassembly of a common type of diagonal mirror cell |
||||
![]() |
![]() |
![]() |
![]() |
![]() |
Use caution when working on these cells. |
We soaked this assembly in mineral spirits paint thinner |
After disassembly the parts can be cleaned with 70 percent rubbing ( isopropyl ) alcohol or |
After cleaning with methanol. |
Re-coated diagonal, diagonal cell and cotton from a vitamin bottle. |
Re-attaching secondary to backing plate
De-coating without separating the diagonal is often possible.
![]() |
Separating a
mirror from its backing plate.
It may not be possible to separate the
mirror from its backing plate if the customer did not space the mirror off
the backing plate or if some type of super epoxy was used instead of the
elastomer. (Silicon sealant or similar.)
With the wood backing
shown it will not be possible to coat the mirror attached to the backing
because it will not be possible to attain the required vacuum for coating.
More 'how to'.
![]() |
When gluing mirrors to their mirror cell be sure to allow the sealant to cure overnight.
More info
This summer (2019) we noticed that our favorite sealant, GE 100 percent silicon which releases the acetic acid smell as it cures is no longer available.
So advise doing a test of your sealant/adhesive/elastomer and allow to cure overnight. If it's still sticky the next day it's probably not usable for attaching mirrors.
RTV means Room Temperature Vulcanizing.
Room temperature should be at least 70 degrees F for at least 24 hours.
We have seen various other satisfactory elastomers used for attaching mirrors.
We just completed testing XtraBond250 (white) and XtraBond150 (clear). We spaced plate glass away from a plywood mirror backing disk with six nickels in three places. After waiting two days we forcibly twisted the glass horizontally to break the bond. The bond failed at the adhesive/plywood interface. We then sanded the three former attachment points with course sandpaper and cleaned with methanol (alcohol) and after it dried rubbed sealant into the roughened area with our finger before pressing the plate glass back as it was before. Waiting another two days we found the attachment to be satisfactory. Over time the sealant continues to cure.
(January 2022)
Update, November 2020