Another Duplicolor Question

[jacko]

I am trying Steve Guthmiller's Duplicolor system and am spraying color coats I am spraying outside and have gotten a significant speck in the 2nd color coat. Should I stop to let it dry and sand out or continue with color coat? Steve, how long do you wait between each primer, color, and clear coat? Thanks, John

[Chariots of Fire]

Depending on the color you are using you may be able to sand it out but in doing so I would sand most of the paint away so that the spot will blend.  Otherwise with Duplicolor being so finely pigmented the spot may not cover well when you reapply the final coat.  Duplicolor dries quickly and quite hard so you should be able to sand within a few hours.  I've used Duplicolor for a long time with great results.

[Mike 1017]

Have you tried to warm up the can with hot water? I used to get clumps spitting out of "cold" can.  It's so aggravating 

Good luck

Mike

[ctruss53]

If you get junk in your paint, stop where you are at and let it cure. Then wet sand to remove the junk.

If you apply more paint over the junk you only magnify the problem.

[StevenGuthmiller]

22 minutes ago, ctruss53 said:

If you get junk in your paint, stop where you are at and let it cure. Then wet sand to remove the junk.

If you apply more paint over the junk you only magnify the problem.

This is exactly what my approach would be.

Be sure to give the paint ample time to cure before you start sanding, (I would wait for a day or two) and clean well when finished, and then re-coat.

 

As a general rule, I wait an hour or two between primer coats, and several hours, at least, between color coats.

As I usually use 4 or 5 coats of color, my routine is to do a couple of color coats per day, 3 or 4 hours apart.

 

 

 

Steve

Edited June 28, 2023 by StevenGuthmiller

[atomicholiday]

13 minutes ago, StevenGuthmiller said:

This is exactly what my approach would be.

Be sure to give the paint ample time to cure before you start sanding, (I would wait for a day or two) and clean well when finished, and then re-coat.

 

As a general rule, I wait an hour or two between primer coats, and several hours, at least, between color coats.

As I usually use 4 or 5 coats of color, my routine is to do a couple of color coats per day, 3 or 4 hours apart.

 

 

 

Steve

Question for you.  What is the benefit of waiting a few hours vs say, 10-20 minutes between coats?

[StevenGuthmiller]

15 minutes ago, atomicholiday said:

Question for you.  What is the benefit of waiting a few hours vs say, 10-20 minutes between coats?

It gives the paint time to cure well between coats which helps to protect what's underneath from any adverse affects from the following coats.

 

Call me nuts, but in my opinion, several coats of paint applied a few minutes apart is more like one thick coat than it is several thin coats.

With a hot paint, it's the nature of the beast that each successive coat will etch slightly into the prior coat which is desirable for proper adhesion.

Allowing each coat to gas out fully, and at least partially cure, insures that the solvents are not eating their way all of the way down through the uncured layers beneath it, which in turn can affect the plastic beneath.

I've found that it's beneficial to be safe rather than sorry, and allowing each coat adequate time to cure insures that there won't be any surprises.

 

Duplicolor, as well as most other acrylic lacquer paints, have no re-coat requirements, so I've never found any benefit in rushing it. 

 

 

 

Steve

[atomicholiday]

25 minutes ago, StevenGuthmiller said:

It gives the paint time to cure well between coats which helps to protect what's underneath from any adverse affects from the following coats.

 

Call me nuts, but in my opinion, several coats of paint applied a few minutes apart is more like one thick coat than it is several thin coats.

With a hot paint, it's the nature of the beast that each successive coat will etch slightly into the prior coat which is desirable for proper adhesion.

Allowing each coat to gas out fully, and at least partially cure, insures that the solvents are not eating their way all of the way down through the uncured layers beneath it, which in turn can affect the plastic beneath.

I've found that it's beneficial to be safe rather than sorry, and allowing each coat adequate time to cure insures that there won't be any surprises.

 

Duplicolor, as well as most other acrylic lacquer paints, have no re-coat requirements, so I've never found any benefit in rushing it. 

 

 

 

Steve

Is there any limit for length of time?  Meaning, is there such a thing as waiting too long between coats?

[ctruss53]

1 hour ago, atomicholiday said:

Question for you.  What is the benefit of waiting a few hours vs say, 10-20 minutes between coats?

There is no such thing as waiting too long. And the longer you wait, the more the finish cures and the harder it gets.

I don't wait hours. But that is probably because I apply less paint than Steve does.

I build up my primer in very light coats. And since the coats are light, they are dry to the touch in 15 minutes. So I'll apply 3-4 very light primer coats, 5-10 minutes apart. This way they are partially cured and can kind of stick together.  After that I wait 1 - 2 days before I apply paint. If I am in a hurry, I'll apply paint the next day, but I try to give the primer two days.

Then I also apply the paint in very light coats. I only wait 7-10 minutes between coats of paint, but again, I am applying it very lightly. I add as many light coats as it takes to get the color nice and even with as little paint as possible. usually 3-5 light coats.  Then I wait at least 48 hours before I clearcoat.

And then clearcoat, I apply clear in light coats as well, to begin with. I apply a few very light coats 5-7 minutes apart. Then I apply 2-4 heavier wet coats, 10-15 minutes apart.  And once clear is on there, I wait at least a week before I'll wet sand it.

But here is where I might do things really different.

After a week goes by and I am ready to wetsand, I put time in between the sanding stages too.  I'll start at 2000 or 3000 grit depending on how bad the orange peel is. I'll wet sand the whole body. Then I let it sit overnight to cure some more now that the "skin" is missing.

The next day I'll wetsand with 5000 or 6000, again depending on the surface. I'll sand the whole body and then let it sit overnight again to cure.

The next day I'll wet sand with 12000.  And after I'm done sanding the whole thing, I'll let it sit overnight again.

The next day I use rubbing compound.

Then the next day I'll use polishing compound.

Then the final day I'll apply Mequires Scratch-X and then wax it.

I learned to put time in between all the steps from a guy I see at model shows. He is always winning best paint. His finishes are always flawless.

[StevenGuthmiller]

1 hour ago, atomicholiday said:

Is there any limit for length of time?  Meaning, is there such a thing as waiting too long between coats?

Nope.

You can wait for a year if you want.

 

 

 

Steve

[atomicholiday]

Good info to know.  Thanks gentlemen!

[StevenGuthmiller]

1 hour ago, ctruss53 said:

But here is where I might do things really different.

After a week goes by and I am ready to wetsand, I put time in between the sanding stages too.  I'll start at 2000 or 3000 grit depending on how bad the orange peel is. I'll wet sand the whole body. Then I let it sit overnight to cure some more now that the "skin" is missing.

The next day I'll wetsand with 5000 or 6000, again depending on the surface. I'll sand the whole body and then let it sit overnight again to cure.

The next day I'll wet sand with 12000.  And after I'm done sanding the whole thing, I'll let it sit overnight again.

The next day I use rubbing compound.

Then the next day I'll use polishing compound.

Then the final day I'll apply Mequires Scratch-X and then wax it.

I suppose that you can allow your curing time between coats of paint, or between sanding grits.

In either case, allowing curing time is beneficial, and the time required will equal out.

When I begin polishing, I will polish entire sections of the body from start to finish in one session, and then move on to the next section.

 

I've just found in my experience that piling on too much paint in a short period has the potential to cause problems.

In this case, very light coats would be required.

I've had plastic craze from piling on too much paint in a short period, even late in the process, so I refrain and give the paint time to cure between coats.

 

I've had very good luck for many years with the system that I use.

I think I've only stripped a couple of paint jobs in the past 10 years or so.

 

 

 

Steve

Edited June 28, 2023 by StevenGuthmiller

[atomicholiday]

Never ceases to amaze me how different people can use the same product but with different techniques and still get great results.  Makes it difficult for beginners to understand how it’s done.

 I guess this just reinforces the idea that you need to experiment and find what works best for your particular style.

[ctruss53]

If there was only one way to do everything this forum wouldn't exist.  haha

[atomicholiday]

27 minutes ago, ctruss53 said:

If there was only one way to do everything this forum wouldn't exist.  haha

Absolutely.?

Sometimes it feels like I learn something new on here everyday.  Of course, half the time it opens more questions.  Love it!

[StevenGuthmiller]

51 minutes ago, atomicholiday said:

Sometimes it feels like I learn something new on here everyday.  Of course, half the time it opens more questions.  Love it!

Your sentiment is understandable.

 

In the end, you're not likely to find very many definitive answers on this, or any other forum.

But you will find lots of ideas that will help you to formulate your own processes.

 

 

 

Steve

[ctruss53]

1 hour ago, StevenGuthmiller said:

Your sentiment is understandable.

 

In the end, you're not likely to find very many definitive answers on this, or any other forum.

But you will find lots of ideas that will help you to formulate your own processes.

 

 

 

Steve

This is exactly it.  I always find 5 ways to do something and jumble them all together into my own thing.

[jacko]

I masked off the spot of grit, then began very lightly sanding with 1000 grit.  The little "island" within the sanded area gradually decreased until almost gone but then the surrounding area lightened slightly. I untaped, decanted a few ccs of my duplicolor dark blue and slowly airbrushed about a 1.5 in. circle around the defect until everything looked the same. I now plan to do a couple more color coats from the can before starting clearcoat.

Thanks, John