Guilding onto card

[OllieG]

Hello,

I have a commission which requires me to guild a large area of card and have come here for advice about what adhesive to use? I know its not specific to framing but I figured you would know more about it than most.

I have 23 carat 80x80mm transfer leaf. Im going to be guilding a pattern laser cut into 300gsm card.

My question is really if conventional size would work? I use things like "wonder size" and acrylic size at work. But I want to avoid to much water warping the card. Would applying a thinner coat, with a roller instead of a brush work? Does anyone have any experience guilding this kind of surface or any advice what size to use or perhaps alternatives? Spray mount perhaps?

Thanks

[vintage frames]

Hi Ollie
This should be a fairly straight forward job.The essential thing is to seal up BOTH sides of the card to prevent any warping. Use a dilution of 50/50 shellac - meths for this and you would need to apply at least 3 coats. If you get any missed areas at all, then the size will soak in and spoil the gilding.
Use Transparent Shellac polish - not white nor button or french. Buy a Pro-Art Proline Flat Series 106 1" brush for this. In fact buy 2. Get them from Jacksons Art Supplies. And while you're there, buy some Marseille soap flakes for keeping your brushes clean.
As I said, paint on 3 coats of shellac allowing 1/2hour drying between coats. Then leave that overnight.
You can use Wundasize if you wish but it's really only a hobby size. For more professional results, buy Handover 3hour size, also available from Jacksons.
With a clean rag in one hand, paint on the thick size to cover say a 6" square area. Be quite liberal and thorough. Now squeeze out your brush into the rag and work your dried brush into the wet size again. The aim here is to pick up as much surplus size as possible but to leave behind a very thin glossy film. The finer the film left, the brighter the gild. Keep repeating that over the whole area to be gilded.
Also have a piece of scrap card set aside as a reference and to which you have done all the above.
After 3 hours, test the size by pressing your knuckle onto the reference card. You should hear a small snap as you lift your knuckle away. If the size feels sticky, then leave it a while yet. With the 3hour size you should have at least 3hour "open" or working time.
When the size is ready, press your transfer leaf onto the surface and gild as thoroughly as required.
The next day, cover the gild with a further coat of diluted shellac and then your work is complete.
One other thing. Do make sure you have enough gold, plus extra, to cover the area to be gilded. You really don't want to run out before the size has gone dry.

[OllieG]

Oh wow! This is such a good response, thank you.

With the shellac I've been looking and do you mean get 'clear' with the amber colouring or get 'crystal clear' which has no colouring but im not sure it's actully shellac?

[vintage frames]

I only specify transparent shellac as all the other types of shellac polish contain additives such as resins, waxes and oils. These are added to aid the use in french polishing. If it's only to seal a base layer, then any sort of shellac should be OK. But as an overglaze, it's best to use a transparent polish. Robersons make one specifically for this purpose, otherwise there is Fiddes or Jenkins. Liberon do one and most of their products are excellent but as they seem to target the DIY market, the concentrations can be a bit weaker.