Painting car parts yourself, help wanted.

[FastFwd]

So basically I want to learn how to paint parts, panels and if possible my whole car. I have purchased and used the following:

• acrylic paint made up from auto1
• acrylic clear coat
• primer
• thinners
• bottom feeder spray gun and 2hp compressor
• 400/800/1200 sandpaper
• compressor sandgun

I've used my gun with primer many times before but never painted because I was to scared but now I'm keen to learn. So i painted my turbo territory front grill today to learn on. It's black siloette paint.

I follower a guide on the net. Basically as follows

Grease and wax remover
Primer
Sand with 400
Grease and wax remover again
Paint 3 coats, 20 mins between each
Sand with 800
Grease and wax remover
Clear coat 2 coats 20 mins between
Sand with 1200

I used 1 to 1 with paint and clear coat as that's what auto1 told me if it's over 20 deg.

My spray gun is bottom feed, $70 gun and could be better.

I have ended up with an uneven looking job. Some looks clear and some looks rough and dry.

What have I done wrong? Is it that my gun hasn't been setup correctly for the spray. It's was very thin application but I made sure it was fully wet looking.

Any feedback or help would be great.

[FastFwd]

This is what it looks like...you can see what i mean

[mocchi]

uneven can be the way you hold the gun not at constant distance & angle. could also be your compressor losing pressure halfway or too high psi at the gun.

if all looks dry n rough, try use a retarder on your paint. this delays the flash point and allows your paint to 'wet' down and kinda level itself giving that wet look.

youll have orange peel.

[Daveho1]

also acrylic isnt glossy off the gun, it needs to be wet sanded and buffed.
may i ask what size nozzle the gun is? realisticly i would use 2mm-2.5mm for puttys, 1.8mm for primer and 1.4mm-1.6mm for bases and clears. also on a small compressor like that you should be using a hvlp gun

[FastFwd]

uneven can be the way you hold the gun not at constant distance & angle. could also be your compressor losing pressure halfway or too high psi at the gun.

if all looks dry n rough, try use a retarder on your paint. this delays the flash point and allows your paint to 'wet' down and kinda level itself giving that wet look.

youll have orange peel.

Can you explain what a retarder is?

[FastFwd]

also acrylic isnt glossy off the gun, it needs to be wet sanded and buffed.
may i ask what size nozzle the gun is? realisticly i would use 2mm-2.5mm for puttys, 1.8mm for primer and 1.4mm-1.6mm for bases and clears. also on a small compressor like that you should be using a hvlp gun

I did wet sand it but I didn't buff it? What compound or product should be buffing with?

Also if i wet sand it more will it even out the current issue?

I don't know what gun head but I will find out and let our know.

What is a hvlp gun?

[jdm_b16a]

So basically I want to learn how to paint parts, panels and if possible my whole car.

I used 1 to 1 with paint and clear coat as that's what auto1 told me if it's over 20 deg.

This is why your finish is like rough sandpaper. Too much paint and not enough thinner.

Are you using General Purpose Thinners or Acrylic Thinners?

GP Thinners is only for undercoating. Acrylic Thinners is for finish coats.

The correct ratio is 1:1.5 - 1 part paint to 1.5 parts thinners.

However, having said that it also depends on the temperature of the day, your technique and the quality of the gun.

If you are using Acrylic you should be using a bigger aperture - 2.0mm tip. 1.4 is for 2pac.

I've asked the question several times at spray painting classes and the answer is always the same. The cost of a respray is not in the materials; it's in the expertise of the painter. You pay for experience.

My spray gun is bottom feed, $70 gun and could be better.

Don't expect a top class job from a $70 gun. But it's a good place to start. You should be using a HVLP (High Volume Low Pressure) gun that feeds via gravity (from the top). Your suction feed gun is less forgiving than the HVLP gun.

What have I done wrong? Is it that my gun hasn't been setup correctly for the spray. It's was very thin application but I made sure it was fully wet looking.

Your compressor should deliver a constant volume of air so that the gun atomises the paint mix correctly. If it's struggling you have no option but to wait until it catches up. Also make sure your line from the compressor to the gun is as short ads possible as there will be a pressure drop according to the length of the line.

There are so many variables that all you can do is get a scrap panel and practice with gun setup, pressure and paint mix.

Also acrylic isn't glossy off the gun, it needs to be wet sanded and buffed.

Not really true - acrylic is glossy off the gun but as it dries (via air evaporation) it loses some of its gloss. Too much thinners will result in that gloss disappearing quickly. I've paint panels that have retained their gloss with Acrylic. Make sure you are using Acrylic (High Gloss) Thinners and not the cheaper General Purpose Thinners.

Good luck.

Peter

[Daveho1]

thiners to paint ratio dose change quite a bit depending on brand, but 1:1.5 is a good starting point.

as for acrylic not bing glossy of the gun i guess i miss typed, but it is common practice to buff and wet sand, compaired to 2pak where if applied well dosnt.

fluid tip wise i stand by what i typed, i know several profesional painters that also agree with me.

[jdm_b16a]

Thinners to paint ratio does change quite a bit depending on brand, but 1:1.5 is a good starting point.

Agreed. I think different manufacturers specifiy varying formulas based on their paint characteristics.

I'd start at 1:1.5 and then play with that until you get a good finish. I know some manufatcurers recommend 1:1 for the undercoats but 1:1.5 or higher gets a better flow and smoother finish.

One thing I've taken on board over the years on Forums and with questions like this, is that you will never get complete agreement on what constitutes "best practice" but each person has a diferent methodology depending on their own experiences. No-one is really "wrong", but the best course of action is to do one of those TAFE short courses or (if you're in Sydney) go to the VG Auto Paints free Saturday morning classes. I've been [amateur] painting for many years, done a TAFE course (12 weeks) and been to two of the VG sessions and I've learnt a lot and improved my technique but I'm still not at a standard where I would safely say "Yeah, I'll paint your car". I've done my own for sure and I'm happy with the results of late.

As for acrylic not being glossy of the gun I guess I mistyped, but it is common practice to buff and wet sand, compared to 2pak where if applied well doesnt.

No question. You are absolutely right. I didn't mention cut and polish as I thought it was a "given" but, yes, even if you get a good finish off the gun, you have to cut and polish to really bring up the finish. One thing about "Acrylic vs 2Pac" is that acrylic requires regular maintenance to keep the finish whereas 2Pac just requires a wash to show it's best. Acrylic is easier to apply and more forgiving - if you make a mistake you can wait a couple of hours then sand back and reapply. 2Pac requires good technique and high quality equipment (not too mention a spray booth and correct safety gear). It took me quite some time to get the hang of painting 2Pac in a booth - it's completely different to acrylic, requires fine atomisation (1.4mm tip) and a constant flow of high quality air.

Remember, acrylic dries through evaporation of the solvents in air; 2Pac is a chemical bonding process. That is why you bake the 2Pac job for the right finish - the paint flows out and levels in the baking process.

Fluid tip wise I stand by what I typed. I know several profesional painters that also agree with me.

See my comment above re: technique and best practice.

Standard practice is smaller tip for 2Pac (due to the fine atomisation I was talking about above) and larger tip for acrylics/primers. Exactly what sizes constitute "ideal" I'll leave that open but again suggest experimentation and what works best for each individual.

Peter

[FastFwd]

Ok i believe its my gun/pressure setup/nozzle setup. So I'm going to purchase a HVLP gun...What is your thoughts on something like this? I know its not a known brand or anything like that but im just starting out and i just want to have a play and hopefully learn some new tricks.

http://www.ebay.com.au/itm/Gravity-F...item53f5a4a127

Or something like this - but it only comes with 2mm tip but i guess im only spraying acrylic for the time being so im sure thats fine.

http://www.ebay.com.au/itm/HVLP-2MM-...item2328d88336

[jdm_b16a]

What is your thoughts on something like this?

They look OK and will allow you to practice your technique and settings.

Peter

[Daveho1]

agreed honestly i have some nice guns but i keep coming back to my old super cheap gun lol i donno it just seems to work, the thing is as im sure you have noticed painting is easy but painting well is very hard. its really a skill that needs practice