The only chipping technique I know anything about is the use of salt. There should be Plenty of youtube on it out there. Seems to me Vallejo paint should work as well as anything for that technique. I know nothing about their own chipping formula though.

I don't pay all that extra money for special chipping fluids. I use hairspray. Two light fast coats over the paint you want to show through and paint the upper color over that. Stiff brush or toothpick with water and you have easy to control chipping. From what I've seen this method works better than those expensive fluids. But to each his own.

I've also just started playin with this stuff. There are several videos online, the most useful I've found is https://www.youtube.com/watch?v=_V-ECqKuyGU, but most are worth watching—lots of different techniques out there. Unfortunately, Vallejo's videos and instructions are minimal. Some things I've learned so far:

• Drying (curing) time is critical, both for the base layer(s), chipping medium, and the final layer.
• Base layer should be fully cured (overnight or forced air). If not, you can get some interesting effects that you may not want. More on that later.
• Chipping medium must dry at least 30 minutes.
• Top coat should dry for about an hour or more. Remember that acrylics cure slowly.
• Some recommend spraying a clear coat over the base layers to protect them. I can see how this might be a good idea, but haven't tried it yet.
• Chipping medium sprays like white glue at 15 to 20 psi. However, it levels pretty well.
• You can dilute the medium water to medium at 1:1, 1:2 with water. I haven't tried it with Vallejo thinner, yet.
• Top coat should dry (cure) for 30 minutes to an hour. I'm going to try leaving it overnight—but I suspect that may be too long.
• Go easy on the actual chipping process, especially if you've applied a continuous coat of the medium. It's easy to take off more than you want.

Things I'm going to try:

• applying the medium with a fine brush where I want it.
• Dipping a toothbrush in the medium and spattering the surface to produce discrete, circular patches in the base coat.

Unusual effects:

Use white as a top coat over a continuous coat of the medium. Wet the surface as soon as the top coat is dry. Remove entire top coat with a soft brush—instant faded paint!

Wet the surface as soon as the top coat is dry. Draw a fine, fairly stiff brush over the surface to produce fine, parallel streaks, such as flow lines.

Spattering with a toothbrush works, but not too well with undiluted medium.

Still working on brush application in specific areas.

Vallejo told me there's no need to spray a clear coat over the base colour.  haven't tried it again though, so can't report how well that works sorry. 

Josh Ryder

I've just starting to use Vallejo Chipping Medium, to some mixed results. I'm laying down a primer, base coat, then the chipping medium. I let those layers dry at least 24 hours. I spray a light final coat over that, waiting around 10 min, then wet that down with warm water, and use different tools to create chips.

When it works, it works great. When it doesn't it creates more of a worn patch, rather then chips.

Can anyone speak into this, changing paints or process, timing?

The mixed results with Vallejo Chipping Medium might stem from factors like paint compatibility, layer thickness, or water application. Experiment with adjusting the final coat thickness and water application intensity to achieve the desired chipping effect. Trying different paints or extending drying times between layers could also improve results. Balancing these factors and practicing with various tools will likely enhance the chipping outcome, creating the intended weathered look rather than worn patches.