220 grit Paint job!?!

[scadaman29325]

When I joined this forum (Awsome! btw), I went back and read every post under 'technique' and looked up most of the sites referenced. I wanted a good looking rocket this time! I could go through all those steps I learned, but it would be repetitive, so let's just say I spent a great while on this rocket.

I put my first coat of krylon blue on (after repetitive priming and sanding), this coat consisted of 3 or 4 VERY light coats from a warmed can. I purposely avoid the 'wet coat' finish, trying to avoid runs, but it was still covered well. when it dried it felt like 220 grit sandpaper, maybe little finer. You could see (almost see) the uniform 'grit'. Yes, I did wipe it down first...

Potential problems:

I am wondering, was my 1st 'dusting' of krylon my problem? The grit was almost the texture of that 'dusting'. I've never had this problem before.

No paint booth? It was too uniform to be actual dust, I think.

Krylon paint? I wouldn't think so. It's my first use of Krylon, but its suppose to be good.

Prep work? Like I said, primed and sanded with 600 grit prior to first painting (several times). Heck, the primer was smoother than this.

Warmed can? Never done this before.


Second Coat:
I made my 2nd coat a little thicker (after sanding). It still was not glass like, but a little (lot?) better. I used 600 grit again and now I'm waiting for a good day for coat number three, then on to some clear coats.

BTW topic:
How about that 'scotchbrite' stuff used as a polisher. I can't find any marked 'fine'. I've seen the standard 'green' and a 'redish' one, and even a very coarse black one used for stripping paint. Is the green or red supposed to be 'fine' or should I look for something else? I wanted to use it for the FINAL sanding since I can't find sand paper finer than 600 grit.


Thanks in advance for y'all's input!

 

[Stewart32]

I'm no expert...

Your preperation appears good. How hot is your warm paint application? It sounds like your paint maybe nearly dry before it hits the subject, thus the gritty sand paper like feel. Perhaps a lower temperature? Good luck.

 

[lalligood]

I would think it pretty important that your subject (the rocket) be warm like the paint too. Otherwise, there might be a chilling effect causing the paint to misbehave during the curing process. The warmed can is typically only used when you are painting below 60 degrees. Soaking the can in warm water for a few minutes warms the paint & makes it more "active". Warming your paint area with a space heater if possible/necessary too.

It sounds like the problem might have been that you were holding the paint nozzle too far from the subject. The paint can actually dry in midair to the point that it causes a dusty effect. Keep the can 9-12 inches away when spraying. Investing in one of those clip-on handles to make it easier to spray continuously is a great $1.50 investment & saves your finger too!

You problem sounds fully repairable. I have used the 3M Polishing Compound (it acts like a 1500 grit abrasive) & plenty of "elbow grease" to buff out darn near all but the biggest mess ups! An 8oz bottle is available for ~$6 in the automotive section of Wal-Mart. Just use a little on a dry cotton cloth in a circular motion. Wipe clean with another dry cotton cloth. Repeat if necessary.

That'll give you the mirror glass finish you were looking for!

 

[Fore Check]

I am fully aware of and painfully familiar with your "sandpaper" finish.

Anyway, I've noticed that this is probably due to your light coats. I use Krylon sprays, and go for that "wet" look. This usually fails when I apply in higher winds, or right underneath an air conditioning/heater vent while that system is running. This tells me that only a light spray is hitting the rocket.

I suggest you sand it with a minimum of 400 grit (maybe 600 would be better) just to smooth it down a tad. Then apply another coat, but lay it on a bit thicker. I suspect your problem will then go away.

 

[flying_silverad]

I have had this problem in the past and I would over up these trouble shooting hints.

Was humidity an issue? If it was humid, it does kill the gloss.

Was the paint warmed too much? I really don't like this method...instead i prefer to let it sit in the same area, hence temp, that I am painting. If your subject was aloy cooler than your paint, this could be an issue.

Primer and Top coat both Krylon?

Holding the can to far away or moving can to fast? Sometimes this lends itself to faster drying without the levelling that you need for gloss.

If you can, let dry for a few days and sand with 400/600 and respray.

 

[astrowolf67]

I usually apply 2-3 good dusting coats, then a couple of good wet coats. The key to getting good wet coats, without runs, is patience. You have to wait until the previous coats are tacked up real good. I usually wait about 5-10 minutes between coats with Krylon. Once the final coat is on, move the rocket into a climate controlled area (about 70-80 degrees, no humidity), and let it set for a day or two.

 

[Hospital_Rocket]

Nobody answered this question for you, however the green and red scotchbrite pads are considered medium grit abrasives. If you want the soft stuff you need to look for white or a light tan color.

Keep in mind these are classsified a extra heavy duty (Black or Dark Blue), heavy duty (green), regular duty (green), and light duty (white). These things work for abrasion, however were designed for cleaning.

A

 

[Lee Reep]

Originally posted by scadaman29325


BTW topic:
How about that 'scotchbrite' stuff used as a polisher. I can't find any marked 'fine'.

I use 400 grit or 600 grit Wet or Dry sandpaper, and wet sand between coats. Be careful not to get the rocket too wet, especially at the ends where there is no paint, since the water can wick into the ends.

Keep the paper clean by running it under water to clear it. You can wipe the rocket with a cloth or damp sponge, or run it under the tap if careful!

I put a laundry tub in my shop -- a real must for cleanup, washing parts, cleaning up after doing household painting, AND wet sanding rockets.