Painting Question - Am I messing up?

[cowboyup3371]

I posted this in my rebuild thread but know some folks don't go in there so am asking again:

While using 1000 grit to sand the tank today, I started seeing white specks but without any obvious dulling in the paint. Am I going too far?

Here's pictures of the tank from a bit of a distance. The best picture for the specks will be the last one:









Should I keep going or stop and buff this thing yet?

 

[rustybronco]

Do the white spots wash off with soap and water (sanding dust), ? or is it primer showing through?

My immediate guess would be surface contamination of your primer.

 

[cowboyup3371]

I took a rag and dish soap to a small area and it seems to have come off but I can't be certain as I still see some. I'll keep trying.

 

[rustybronco]

Did you use gray primer?

 

[cowboyup3371]

Yes I did...will that be a problem?

 

[Paul]

did you use a rattle can or compressor?, I had white flecks in my lacquer coat, the guy didn't use a water trap on the compressor and it chucked out tiny droplets, if it were me I sand till you have an even surface unless you're going for a hammerite effect, even if you have to end up putting a few more coats on top

 

[cowboyup3371]

We used a compressor with just a filter in the gun.

Thanks, I'll keep at sanding it. Doing dinner now as we have a parent teacher conference soon.

 

[posplayr]

Just based on the pictures I would say that you have way too much orange peel to get a smooth finish. What I mean is the white spots are trapping dust because they are so deep and you would literally have to sand to the color to get them out. The likely hood of sanding through the clear is going to increase. I would just an on des praying with another clear cost after roughening it up with 400 grit. That way you will at least save the color coat. You also need to get that clear to flow better. It looks like it is going on too dry. Move the gun a little closer.

 

[rustybronco]

Yes I did...will that be a problem?

The gray primer isn't the issue, it's contamination of it or your paint that is. The more I look at your photo, the more I believe it's from your compressor and or air hose. You need to get rid of the surface contamination before trying to respray and stop whatever is causing it from happening again.

The filter in the gun will not stop anything but large particles, such as a piece of dried paint off the edge of a paint can. I removed mine and use paper strainers instead.

 

[cowboyup3371]

We did use a paper strainer when pouring the paint into the gun but the only filter on the gun is the one inside of it.

I will get back to it tomorrow night as I'm at my daughter's swim practice right now

 

[Guest]

Just based on the pictures I would say that you have way too much orange peel.

Yes, that is orange peel to the max.

 

[Fjbj40]

That is pretty heavy orange peel! What pressure you spraying at? What type of gun? Sand with 800 and hit it with 2-3 more coats of clear. Then wet sand again.

 

[cowboyup3371]

We are using a harbor freight gun with two filters at the paint and air side (I stand corrected after talking to my friend and looking at the gun). Pressure was at 80psi (+/- 5psi) when we shot it.

I'll keep working through it.

 

[almarconi]

Do you use a dedicated hose just for your spray gun? Not sure what type of paint you used but dry and oil free air is pretty much a necessity for automotive type paint.

 

[nvr2old]

How many coats of clear do you have on it at this point? It looks like you've barely sanded any of it off at all at this point. Looks to me like it's just sanded off wet clear residue that's settling into the recesses of the orange peel, or maybe dirt specks that got into it and you're sanding into those. If you have at lest 3-4 coats on it, I would continue sanding it until the orange peel goes away. Check it by wiping it dry, constantly. As long as you see white..and no blue residue while sanding..you should be fine. Are you using at least 800 at this point? Anything less will never cut it flat. Are you using a soft block with your sand paper, also? If not, you should. It'll make your life so much easier. If you're feeling uncomfortable about sanding through, because you still need to go to 1,000-1,500-2,000 and then several polishing steps..I would get it close to smooth with the 800 and then spray a few more coats of clear. Maybe thin it down just a touch so it flows out smoother. Heat will also help immensely to make it flow out. Anything less then 60 degrees and it'll just sit there. 70-80 degrees is perfect. You also need to purchase reducers specifically for the temperature you're spraying in, too.

There's a lot to this painting stuff. So many variables to consider. It's expensive and it's scary, no doubt. I've done it for 40 tears and I still have to think about it, plan for inconsistencies, and then figure out what to do to fix it if it goes bad. I've been through just about every scenario. You're not alone.

 

[stiksave]

80psi is high. I just sprayed my son's Jeep this morning,60 degrees +-, 3 coats color, 1 coat clear. 60psi at the compressor, 45 +- at the gun, old syphon gun, paint from Eastwood. Glass.

 

[SVSooke]

Yeah 80 PSI is way high.IIRC I did mine at 45 PSI

 

[cowboyup3371]

Thanks guys. I'm going in at it again later but I have two different homework assignments to help with so it may not happen tonight.

I was just using my hand instead of a block Larry so I'll swap to that. And I'm using 1000-grit right now; I can drop down but I was afraid of going too far.

 

[Govee]

I had fisheye on my car that was as bad or worse and had to use 600 grit as the first course. 1000 just would not eliminate the fisheye. I did not use a block and I used lots of water (with a little dish washing soap) and had really good results and only burnt through a couple tiny spots near an edge.

 

[nvr2old]

A soft sanding block is better because it not only covers a larger area, but it sands it evenly w/o leaving grooves that your fingers develop. 1,000 just won't cut through that much orange peel. You want it to cut quickly and evenly. The 1,000 will only remove the 800 scratches and so on. It's a step by step process of removing the previous sand scratches left by the coarser grades until you hit it with a coarse rubbing compound with a wool pad followed by a medium compound and a yellow foam pad and finally a black foam pad with a swirl remover. So many people skip steps and wonder why there are still scratches showing. Follow the steps and it works fine.