sand like appearance of paint ...

[Guest]

Hi , i tried to achieve chipping with salt.

First I applied black alclad primer (super!!)

then alclad aluminum (super!!)

then salt and gunze aqua color diluted 50-50 with IPA (not so super...)

the result is a sand like effect on the final color..

is it airbrush/color/pressure problem or something has reacted badly ?

thanks

makis

[stona]

Your problem has almost certainly been caused by the paint drying before it has formed a layer on the model surface. This maybe caused by spraying from too far away,but ther are many factors effecting the rate at which the paint dries after it leaves your airbrush nozzle. I'm not familiar with your paint system but I notice that you thin with IPA which is very fast drying.

Cheers

Steve

[Guest]

I think your right Steve. IPA is great for washes and pin washes because of its evaporation rate. This im almost certain will be a problem when diluting paint as it will evoporate at it atomises causing the paint to dry miliseconds before impact leaving a sand blasting effect. Adding the factor of distance to the model will make the paint drying factor even quicker. Just my opinion, i stand to be corrected if necessary.

Andy

[Guest]

Your post doesn't make it very clear, can you confirm that you added salt to a wetted surface shaped where necessary and left it to dry thoroughly then pained over with your acryl.

If so, you shouldn't have had any problem, if not if you could clarify your procedure and one of us should be able to point you in the right direction.

[Guest]

I think your right Steve. IPA is great for washes and pin washes because of its evaporation rate. This im almost certain will be a problem when diluting paint as it will evoporate at it atomises causing the paint to dry miliseconds before impact leaving a sand blasting effect. Adding the factor of distance to the model will make the paint drying factor even quicker. Just my opinion, i stand to be corrected if necessary.Andy

I spray Tamiya acryl thinned with IPA, it's all i've ever used and never had this prob, if you sprayed at a great distance from the model, or at too high a pressure or in a very very hot room then it could happen, otherwise it should be fine.

[Guest]

Just re-read and noted you mention Gunze aqua, if this is the same kind of formulation as revell aqua the thinning agent would be a problem, when I thinned revell aqua with IPA it coagulated and clogged the AB very quickly and didn't spray well at all, you'd need to thin with water or it's own brand thinner.

[Guest]

concerning the salt procedure I let it dry overnight . It was the first time i diluted gunze with IPA , till now I diluted it with window cleaner with no significant problems , but read that IPA makes an excelent finish .

I will try adding some water and probably reduce the heating in the room. I will post the results.

[Guest]

ok ,here are the results. I sanded the areas with 2000 grit wet and resprayed with gunze diluted with IPA at a 70:30 ratio. It seems ok. probably there was too much IPA in my first solution , hence the quick drying time.

I will try adding a few drops of acrylic retarder next time.