clear coat and polishing problems

[carro]

Hi i have a dilema I know every now and then at one point or another when building model cars you come across a problem you have never seen before, specially with the painting process.I have been building models for a while now and the last 3 kits I have painted I have come across into the same problem, now before I mention my problem I have been using the same techniche for over 8 years the same brand of primer paint and clear witch is Duplicolor. I have been using the same airbrush, the same air pressure ,and yes I have a water trap on my airbrush air line and never had a problem with my paintjobs till mid this year. My problem seems to be in the clear but not while spraying it on or after the drying process, but after the polishing process. I always use primer sealer on my car let it dry for a couple of days then spray the base coat, then let that dry anywhere from 4 to 7 days (by the way is all duplicolor laquer paints) then spray the clear on let it dry for atleast one or two weeks, then I polish it.The polish I use is Meguiars scratch x fine scratch and swirl remover. And like I said I have been using the same process for many years and after I finish my models I put them in diplaying cases and never touch them again. Except for the last 3 models I painted when I look at my other models meaning my older ones witch I painted using the same process look as good as the day I finished them.Ok my problem is not fish eyes or crows feet or the usual problems that you mostly see on the clear .I noticed on all 3 models the imperfections seem to pop up 2 to 3 days after the car has been polished and the only way I can explain it, is that the clear looks like shatered glass, is stiil a perfect shine and if you touch it is extremely smooth but it looks like there is shatered glass under the clear. Please help! I'll try anything im getting to the point where im not starting anything else because Im afraid of having to strip more paint jobs. Thank you! here is a couple of pics so you get a visual.

[diymirage]

wish i could be of any help but all i can say is wow, that looks dead on like a fiberglass bumper on a poorply pimped out eclipse, i mean, it looks like the way cheap fiberglass crackes under strain

very intresting

[OneTrickPony]

Is it possible that Duplicolor has changed it's formula on one of the products you use? I know with changing EPA regulations that can happen.

Maybe you just got a bad batch of something?

[Zoom Zoom]

Tamiya at least used to have a similar problem w/their clear; if it wasn't applied to freshly-applied color, you had to wait a month to apply or it would crack over time.

This is a case where your clearcoat is drying/shrinking over the color at a different rate. That's what Tamiya said was the problem w/their clear. I had a similar thing happen to a model I shot in HOK paint and Tamiya clearcoat; even though I shot the clear immediately, after several days a series of microscopic cracks appeared in the paint. You can't feel them or even see them in direct light, but with side lighting you can see them. They didn't get worse and the model is kept in a case. The clearcoat cracked as it dried since it wasn't chemically the same as the color coat and it didn't dry/shrink at the same rate. Lacquers seem more susceptible because they shrink a lot and are not terribly flexible when dry.

Duplicolor may have changed something with their paint. Since you airbrush, you should do some testing. Instead of letting the color dry before applying clear, start applying clear immediately after color. Build it up in very light coats. You can also start mixing clear w/the color for mid-coats; so that the clear is chemically part of the color coat. This should help to alleviate the problem. I use a food dehydrator to dry paint, I do not wait weeks for paint to dry to add other layers or polish it out.

[Brendan]

I have had problems with DupliColor doing the same thing. A friend of mine told that as soon as you spray down the base coat, let it sit for maybe 10 minutes and then shoot the clear over the top. It seems to work with the cars I used DupliColor on.

[MikeMc]

Tamiya at least used to have a similar problem w/their clear; if it wasn't applied to freshly-applied color, you had to wait a month to apply or it would crack over time.

This is a case where your clearcoat is drying/shrinking over the color at a different rate. That's what Tamiya said was the problem w/their clear. I had a similar thing happen to a model I shot in HOK paint and Tamiya clearcoat; even though I shot the clear immediately, after several days a series of microscopic cracks appeared in the paint. You can't feel them or even see them in direct light, but with side lighting you can see them. They didn't get worse and the model is kept in a case. The clearcoat cracked as it dried since it wasn't chemically the same as the color coat and it didn't dry/shrink at the same rate. Lacquers seem more susceptible because they shrink a lot and are not terribly flexible when dry.

Duplicolor may have changed something with their paint. Since you airbrush, you should do some testing. Instead of letting the color dry before applying clear, start applying clear immediately after color. Build it up in very light coats. You can also start mixing clear w/the color for mid-coats; so that the clear is chemically part of the color coat. This should help to alleviate the problem. I use a food dehydrator to dry paint, I do not wait weeks for paint to dry to add other layers or polish it out.

LISTEN TO BOB

[E St. Kruiser50]

I have had problems with DupliColor doing the same thing. A friend of mine told that as soon as you spray down the base coat, let it sit for maybe 10 minutes and then shoot the clear over the top. It seems to work with the cars I used DupliColor on.

Hey Brendan

Absolutely true in my experience.

It's known as "Painting wet in wet".'In my experience and talking to guys over the years who paint the 1 to 1 cars, and my own experience painting, letting the paint dry too long between coats can be disastrous.

When you paint a wet coat over a completely dry surface, the wet wants to shrink, which is a normal part of the drying process, and something has to give, also if there are chemical problems with compatibility, that just adds to the "Pandora's Box". Been there - done that

For centuries artists who paint wth oils, and now with acrylics, have used this wet in wet process to blend colors and texture's. The same process works just as well today.

I can even "PAINT LACQUERS OVER ENAMELS" with zero attacking, spraying the lacquer over enamel that has set for just a few moments. Spray one color enamel, and as fast as you can, pick up the can of lacquer and spray a second color, using the Wet in Wet process combining one color over another, I call layering, and then in just a few moments later, start the clear-coating process, with no ill-affects, and be done with a beautiful paint job in less than an hour.

Yeah - no kiddin

Hope this helps - dave

Edited December 6, 2008 by Treehugger Dave

[carro]

Is it possible that Duplicolor has changed it's formula on one of the products you use? I know with changing EPA regulations that can happen.

Maybe you just got a bad batch of something?

Thank's I tought that with the first kit it happened to so I went and bought more clear before I started on the second one I had a problem with just in case that was the problem (getting a bad batch ) But on Duplicolor changing something in their formula due to the epa regulations you may be right . Thank you all for taking the time to look at this and giving me feedback. I will be trying the wet on wet aproach on my next one! And if that don't work I guess i'll be changing the brand of products I use.

Edited December 6, 2008 by carro

[E St. Kruiser50]

Thank's I tought that with the first kit it happened to so I went and bought more clear before I started on the second one I had a problem with just in case that was the problem (getting a bad batch ) But on Duplicolor changing something in their formula due to the epa regulations you may be right . Thank you all for taking the time to look at this and giving me feedback. I will be trying the wet on wet aproach on my next one! And if that don't work I guess i'll be changing the brand of products I use.

hey carro

Don't give up on the Duplicolor.

To me it's a really good quality of paint for "rattle cans".

For clear, I like to use Plasti-kote #349 clear Classic Lacquer.

I do the "Typical " three coat, 15 minute thing.

Real car builders as well as guy's who write articles in the modle mags tell you;

1) One light coat of color

2) Wait 15 minutes

3) Second coat a little heavier........ you know the drill.

After the third coat wait 15 minutes and start with the clear. Same thing all over again.

With the right compatible brands, it's a system that will serve you well for years.

A little tip for ya.

I only wait for a day before I start the "Rubbing Out" process, because I have found that the clear plasti-kote lacquer I mentioned will actually smooth out under the pressure of "Rubbing".

I hardly ever need to sand the clear as that breaks that beautiful glossy surface that smooth's out so nicely.

I learned this technique, from painting urethanes and actually reading the instructions in the Valspar HOK tech book, on using their products and finishing - WHAT A CONCEPT HUH?

They recommend on their final clear coat, not to wait more than 24 hours for the final polishing to begin, otherwise it dries hard as a rock and doesn't finish nearly as well.

What I've found over and over is, if all else fails, read the instructions , and talk to an expert.

Too many guy's try to come up with their own "System', and hear over and over about the problems their having.

Anyhow, I begin with Novus #2 and a really nice soft blue cloth that I get from Tap Plastics especially made for polishing Plexiglass and being used with the Novus.

Next, I use Finesse-it II #05928, a finishing material I get from a local body and paint supply store.

Lastly, I use Meguiar's Mirror Glaze, #7 Professional Show Car Glaze polish - not a wax and can be painted over.

Shines like wet glass.

Hope this helps

All the best - dave

Edited December 6, 2008 by Treehugger Dave

[carro]

hey carro

Don't give up on the Duplicolor.

To me it's a really good quality of paint for "rattle cans".

For clear, I like to use Plasti-kote #349 clear Classic Lacquer.

I do the "Typical " three coat, 15 minute thing.

Real car builders as well as guy's who write articles in the modle mags tell you;

1) One light coat of color

2) Wait 15 minutes

3) Second coat a little heavier........ you know the drill.

After the third coat wait 15 minutes and start with the clear. Same thing all over again.

With the right compatible brands, it's a system that will serve you well for years.

A little tip for ya.

I only wait for a day before I start the "Rubbing Out" process, because I have found that the clear plasti-kote lacquer I mentioned will actually smooth out under the pressure of "Rubbing".

I hardly ever need to sand the clear as that breaks that beautiful glossy surface that smooth's out so nicely.

I learned this technique, from painting urethanes and actually reading the instructions in the Valspar HOK tech book, on using their products and finishing - WHAT A CONCEPT HUH?

They recommend on their final clear coat, not to wait more than 24 hours for the final polishing to begin, otherwise it dries hard as a rock and doesn't finish nearly as well.

What I've found over and over is, if all else fails, read the instructions , and talk to an expert.

Too many guy's try to come up with their own "System', and hear over and over about the problems their having.

Anyhow, I begin with Novus #2 and a really nice soft blue cloth that I get from Tap Plastics especially made for polishing Plexiglass and being used with the Novus.

Next, I use Finesse-it II #05928, a finishing material I get from a local body and paint supply store.

Lastly, I use Meguiar's Mirror Glaze, #7 Professional Show Car Glaze polish - not a wax and can be painted over.

Shines like wet glass.

Hope this helps

All the best - dave

I really apreciate it Dave. Now about the clear plasti-kote lacquer do you know if that is compatible with Duplicolor lacquer paints?

[E St. Kruiser50]

I really apreciate it Dave. Now about the clear plasti-kote lacquer do you know if that is compatible with Duplicolor lacquer paints?

O yeah.

Been usin' them together for at least 5 or 6 years. Very compatible and gives a beautiful finish.

Temperature is very important when shooting lacquer colors and clear.

I live in Oregon, and the ambiant air temp. is all over the map all year long.

I like to have a dependable temp., so I have a temperature controlled small walk in spray booth, 5X10, that's also lit and vented.

I like to shoot the lacquers at at least 80 degrees, after I've warmed the spray can.

90 degees makes the paint lay down and dry smooth and glossy, and oh so nice

Have fun - dave

Edited December 6, 2008 by Treehugger Dave

[carro]

O yeah.

Been usin' them together for at least 5 or 6 years. Very compatible and gives a beautiful finish.

Temperature is very important when shooting lacquer colors and clear.

I live in Oregon, and the ambiant air temp. is all over the map all year long.

I like to have a dependable temp., so I have a temperature controlled small walk in spray booth, 5X10, that's also lit and vented.

I like to shoot the lacquers at at least 80 degrees, after I've warmed the spray can.

90 degees makes the paint lay down and dry smooth and glossy, and oh so nice

Have fun - dave

Thanks again Dave I really apreciate all the tips and answers you have given me.

[motorcitymadman]

dude i use waterbase tamiya paint and waterbase clear no problem, i usually put about 6 to 10 coats of finsih colour and depending on decals i wait two days up to one week after decals are put on then wait 3 days then shoot clear usually 6 to 10 coats i shoot all coats one after a nother no drying time at all between coats by the by the by using air brush on so it is thin layers of paint and clear. build 1/12 tamiya f-1 models started in 2000 so far 14 awards plus best of show 2 times back to back. so hang in there im 61 if i can learn any body can learn. esp. a kit costing over 100.00. rots-a-ruck holmes

Edited December 9, 2008 by motorcitymadman