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

http://i.imgur.com/0ILTI0j.jpg

[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-Fed-Feed-HVLP-Spray-Paint-Painting-Gun-1-4mm-1-7mm-2mm-Tips-Included-/360603492647?pt=AU_Building_Materials&hash=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-SET-UP-SPRAY-GUN-POLISHED-plastic-pot-/151009133366?pt=AU_Air_Tools&hash=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

[FastFwd]

Aight, I have purchased the first link. Give that a go, work on my technique and go from there. I believe the issue with my current gun is it is 1.4mm or less using acrylic paint. And the 2hp compressor can't keep up with the bottom feed gun. That and the paint to thinner mix.

[MassiEk4]

Just out of curiosity, did you fiddle with the spray gun's setting while you were spraying.
The dry spots might be because you weren't spraying enough paint through the gun's nozzle.

[FastFwd]

Just out of curiosity, did you fiddle with the spray gun's setting while you were spraying.
The dry spots might be because you weren't spraying enough paint through the gun's nozzle.

Yeah i did and i wound it all the way in and all the way out, it was making a difference when i wound it all the way out but not enough. But like other users have mentioned that i could be spraying through a nozzle smaller than 2.0.

Few issues i did feel was the spray wasnt constant pressure, it wasnt a solid constant stream of paint when i sprayed, and when it was at its best it just didnt feel think/wet enough. Could that also because of the thinners to paint mix? some guys mentioned running a 75/25 or a 60/40. I was running a 50/50, will running a thicker paint mix also make it wetter, and with a combination of a 2.0mm head and a top fed gun which i have purchased and just waiting for delivery. I could be resolving most of my paint issues.

I want to get to a point where my setup is dialed in and i can just work on my technique.

[jdm_b16a]

Yeah i did and i wound it all the way in and all the way out

You need to understand what the adjustments on your gun do. If you continued to spray whilst adjusting the nozzle this would explain for the most part the varying finish you were getting.

http://www.global-b2b-network.com/direct/dbimage/50354445/HVLP_Spray_Gun.jpg

In the above example:

(1) the smaller topmost knob allows you to spread or fan the spray of paint. You should aim for a hand width pattern so spray a demo on a piece of scrap metal and then spread your hand out so the resulting spray is the width of your hand from thumb to fingers.

(2) the larger of the two knobs (2nd from the top) controls the needle aperture. Wind it all the way in and then there is no fluid (paint); all the way out and then you have maximum fluid flow. You should aim at somewhere in between usually about 2/3 way. Trial and error, and practice.

(3) On more expensive guns you can also have a third knob which controls the amount of air into the gun. This is usually on the bottom of the handle as in the example above.

The fact you still had problems suggests

(a) your mix was too much paint not enough thinners and

(b) your aperture nozzle was too small to allow enough fluid out.

Another factor is the temperature of the day and therefore the temperature of the panels. If its hot paint in the shade as a hot panel will evaporate the thinners from your job too quickly; too cold a day and you might have to warm up the panels a little with a heat gun.

Also note that you can also change the fan pattern from vertical to horizontal by loosening and turning the cap 90degs.


Few issues i did feel was the spray wasn't constant pressure, it wasn't a solid constant stream of paint when i sprayed

Simply put, your compressor wasn't replenishing air quickly enough - not enough pressure - it couldn't keep up with you. You need to work around this by slowing down and giving the compressor a chance to catch up. Do small sections at a time.

A key factor here is making sure your air hose to the gun is as short as practicable.


Will running a thicker paint mix also make it wetter?

No, it will make it worse. Think about it, the more paint the harder the compressor has to work to push the thicker fluid through the gun, and a small aperture compounds this. That's why you need 2.0mm tip and needle. The reason you add thinners is, as the name implies, to thin the fluid and allow the gun to 'atomise' the paint mix and air for application to your panel.

Also be careful here. You have to match the 2.0mm needle with the 2.0mm air cap. They should be stamped. Don't mix and match 2.0mm needle with a 1.4 or something else air cap.


I want to get to a point where my setup is dialed in and i can just work on my technique.

Absolutely. Your local library will have some spray painting books - they might be a little bit old but the general technique has never changed.

Failing that, look around the web for this ...

http://ecx.images-amazon.com/images/I/41q96jUigML.jpg

Great book with useful setup hints and how to's with lots of photos.

Also don't be lazy because at the end of the day you will be tired even exhausted as spray painting is a physical and mental strain. You have to make sure you disassemble all your equipment and clean it thoroughly otherwise paint will dry inside the gun and block airways etc. No. 1 priority is a clean setup to work at it's best. Which also means when you reassemble you have to recalibrate for the next job, but that's part of the fun. A setup from one day may not be ideal on another day - remember the temperature, and also if its humid there's more water in the air so adjust, adjust, adjust.

I think you are probably coming to realise why spraying a whole car costs what it costs!

Good luck.

Peter

[jdm_b16a]

Go the VG Auto Paints (http://www.vgautopaints.com.au/) site. They have lots of info for the budding car painter.

As I said before they also have lessons and demos on Saturday mornings - they had one last Saturday focussing on painting with 'candy' paint.

These guys know their stuff and these demos aren't just 'hard sell' opportunities.

Plus they have a raffle and a BBQ so you can get fed after the demos and even maybe win some car care prizes.

I've been to a few of these (and yes I do buy all my supplies from these guys because they're local and are helpful with advice)

Peter

[FastFwd]

I will be receiving my new gun in 1-2 days so once i get it i will prep my area and give it another try. Unfortunately im in perth so i wouldn't be able to make the saturday lessons or else i would defiantly do it.

Thanks a bunch for your information. I will be prepping a nice little area in the next couple of days to start my painting this long weekend.

So just for example. This weekend in Perth will be around 28-31 degree's but i will be doing all my painting in my shed in the shade. What thinner mix should i be running then? 60% thinner 40% paint?

[jdm_b16a]

What thinner mix should i be running then? 60% thinner 40% paint?

Start with the usual 1:1.5 mix (1 part paint to 1.5 parts acrylic thinners; or general purpose thinners if only doing undercoat)

The paint should go on "wet" but flash off and be touch dry in about 10 minutes. Just keep the panels out of direct sunlight.

Although you could put them out for a minute or two to warm up and then bring them inside and paint. If they're 'hot' to the touch then wait awhile.

Let us know how you go.

In the meantime here's some self promotion on my part to inspire you ...

This is a DA9 that was Milano Red, now Type R yellow. This is only colour coat - no gloss lacquer applied.

http://i46.tinypic.com/21oziat.jpg

http://i45.tinypic.com/iyjsqe.jpg

http://i46.tinypic.com/x3hncy.jpg

http://i48.tinypic.com/f1zi8z.jpg

http://i50.tinypic.com/347bonl.jpg

http://i45.tinypic.com/25klv9t.jpg

http://i49.tinypic.com/30w3vyb.jpg

http://i47.tinypic.com/2r7vy3d.jpg

http://i49.tinypic.com/t4ww79.jpg

This is an ED6 Civic project

http://i38.tinypic.com/2rz8gm1.jpg

This EG5 Civic was oncer an automatic in silver, and its now one of a few in Grand Prix White (not buffed in these photos)

http://i56.tinypic.com/2hfoscl.jpg

http://i53.tinypic.com/5n7odg.jpg

http://i52.tinypic.com/2s84ivp.jpg

Yes I even paint behind the door skins

http://i56.tinypic.com/9u6ed2.jpg

http://i56.tinypic.com/e02zdf.jpg

Turning these

http://i51.tinypic.com/2dj79eq.jpg

into these

http://i51.tinypic.com/vp8fp4.jpg

into these

http://i56.tinypic.com/28ux3n.jpg

Peter

[FastFwd]

wow a lot of inspiration for me. great work, cheers.

[jdm_b16a]

I've been painting for almost twenty years so don't expect to pick it up quickly - take your time, develop your technique and practice, and keep learning. It's all down to preparation.

Peter

[FastFwd]

Peter,

I did some painting on the weekend. Basically did all of the same as my original post but with new hvlp gun the correct thinner mix and this is how I went.

First and second coats of paint went awesome, looked really good. Issues came whilst painting the clear coat and after. I don't know if ii was doing it correctly or the correct mix of thinners but some parts of the panel came out perfectly clear coated and some came out with a haze of white almost looked like dust. It was kinda like over spray residue leaving a film of dust and I had to go back over it. When I went back over it, it was fine. After 3 coats of clear I got a perfectly sprayed panel. About 10 minutes after the last clear coat it was decently touch dry so i put the panel on the car. After that all he'll broke loose. All the paint started to bubble. It was hot outside that day so I believe it was the heat which I should have left it in the shade but can you confirm this for me so I don't do it again.

[jdm_b16a]

Hazy white : too much product through the gun - back off the amount of paint/clear. Basically you need more air and less product. On the other hand could be you got too close to the panel. The paint should be atomised into a fine mist.

Bubbles : you had too much thinners and it ate through to the original paint, causing a reaction that was incompatible. I've done it myself - sand it all off and start again!

Personally you don't need three coats of clear. You're thinking if one coat of clear is good, three will really make it glossy! Not so, the real shine is in the cutting back and buffing/waxing.

Trial & error is the learning process.

Cheers
Peter

[BG-33P]

Love your work peter. Always refinishing cars to a clean OEM standard. Wish i had the space to practice my own painting.

Good luck with the project fastFwd.