Type of varnish to apply prior to pin washes and weathering?

[JoeB]

I have had a slight problem recently with applying washes and weathering after the decal stage.

 

I applied Pledge varnish prior to the wash and then the washes, which seemed to bleed into the prior acrylic paint coats and make a mess. I removed all the paint and started again.

 

My question is what type of varnish should you apply?

Is is dependent on the type of washes and weathering you apply? For example if its an acrylic based wash should you apply a non acrylic vanish to prevent the two from mixing, and causing the problem I had? If its oil based washes and weathering then is it another type of varnish compared to the acrylic type washes?

 

 

[daneel]

Tbh, I never had particular luck with acrylic type varnishes, they would always end up too thick to be of any use. To make matters worse, you'd need to experiment with enamel washes to make sure the wash won't harm the varnish on the model. Oil washes would always be iffy because their volatility would depend on the thinner medium and the length of time it stays on the model. Now I use lacquer varnishes exclusively and avoid the problem altogether. Gunze GX100 is tough as nails and goes on the model perfectly. It can also be sprayed in a super thin layer that won't obscure the details. And you can put any kind of wash on top, it won't harm the varnish.

Edited January 11, 2023 by daneel

[treker_ed]

How long did you leave the varnish to cure before applying the weathering wash?

 

If it was not fully cured, then it could affect the varnish, and underlying paint. I've had this happen to me on some previous models as I was a bit too impatient. I've learnt the hard way that I have to leave any varnish at least 24 hours before applying any washes, anything less and it came out looking as it the airframe had not been cleaned for the entirety of its operational life! 

[JoeB]

I think it was less than 24 hrs so maybe more patience is required. I will try some more wash on a patch that is yet to be repainted and see.

[Casey]

56 minutes ago, JoeB said:

less than 24 hrs so maybe more patience is required.

It sadly is, especially with high gloss varnish that has a retarter (which helps levelling it up). I would say 24h is an absolute minimum. It is extra durable, but being dry does NOT mean it is already cured. Freshly dry layer of acrylic paint is usually quite fragile, and depending on your humidity and room temperature, it may even need 72h to cure.

[JoeB]

Im only just back into modelling, the last one I built was when I was around 16 so quite a few years ago! Things have changed, and I have more patience fortunately.

This is the problem I was having.

 

[daneel]

Like others have said, dry to the touch doesn't mean it's fully cured... and different varnishes have different curing times. While 24h is a bare minimum, you're much better off letting it cure for more than that. At least 3 days would be my recommendation. I have developed a workflow where I pause for a week with a model right after varnishing, and in the meantime I work on other models. This proved to be a good solution, and never had a problem since.

[JoeB]

Thanks everyone for your help