Glazing of old oil panting

[Fellows Framing]

Advice wanted please.

I would avoid glazing touching paper art work but does the same apply for old oil painting on canvas?

Its from 17 century and will be cleaned and re varnished before display in a museum in its original gilt frame. Given the varnish protection over very cured oil does it matter if the glass touches it? Glazing is needed for protection from visitors, namely children touching it.

If it does whats the best way to go about keeping the glass away. I can build up the back of the frame to ft in spacers but then you are altering the frame.....

Thanks all in advance.
Sarah

[JFeig]

The oil might be dry after 300+ years; however, the varnish might not be fully cured.
An air gap is always recommended.

[JKX]

Yes it needs spacing and being in a public place, acrylic may be a good idea, more for anti- vandalism than safety. but if uv and optically coated then very expensive, but I’d offer it first anyway.

I’d also suggest if being protected by glazing, to skip the re-varnishing!

The back must be sealed as well.

.

[Fellows Framing]

Thank you both.

[Justintime]

I'm wondering if off-gassing is an issue with revarnishing and if it should be left some weeks before glazing? Especially with filtered glazing.

[Timh]

Hi Sarah
Definitely use a small paper wrap fillet.
Any moisture caused by contact of glass to oil painting may cause something called blooming when the varnish looks milky in spots.
This can happen with fresh or old varnish
More often with older varnish when there's some cracking.
Securing the back is also a good idea and I use 3 mm acrylic with a few small air holes drilled in to promote good air circulation.

[JKX]

Read this sixteen year old thread

https://www.thegrumble.com/threads/told ... 764/page-2

[JKX]

Securing the back is also a good idea and I use 3 mm acrylic with a few small air holes drilled in to promote good air circulation.

Why acrylic ?

Backing gives protection from dust and insects, drilling holes in it writes that protection off.

Air can permeate anything besides glass and metal anyway and even if backed with either of those, making a frame totally airtight is impossible for most framers.