Spray Painting Tips

thrax · 23rd November 2004, 6:04 PM

Has anyone got any good tips when it comes to spray painting you're case with either a spray can or a spray gun + air-compressor. It’s been awhile since I’ve actual try to do this, and more so when I actual had done it was back in high school’s shop classes which seems like a lifetime ago

. But I still remember a few fundamentals of what to do.

Stand a fair distance way from the object to avoid spatting
Take you’re time, no need to rush it
Allow up to 30 mins for the applications to dry
for an effect coat, lightly sand the applied area, and give it another light coat and repeat until satisfied.

If anyone has an good suggestions I will be more than happy to update this thread with the information, more of less this will become a reference thread for those people interesting in give there cases or other objects a bit of face lift

Things to do before painting

You should be wearing proper painting attire, i.e. old shoes, shorts and shirt.
Work in a well-ventilated area. I can't stress this enough.
Cover near by objects. The over-spray will travel farther than you think.
Rinse the objects you wish to paint, and dry them thoroughly. Make sure you wipe off ALL LINT, otherwise, you will just paint it to your surface, and leave a mark after you sand it out.
Wear a protective mask. I use a wash cloth over my mouth and nose. Trust me, the headaches you get from not wearing it, are not worth it. You will learn to hate the smell of paint, guaranteed.

Applying Your First Coat
The primer should be a relatively thin layer of paint. It does not have to be perfectly smooth, so go briskly over the surface, don't go slowly like you would with the color and clear coat. If you use too much primer, it becomes gummy and UN-paintable. Always spray away from your. This forces and pushes the over-spray past the surface. If you spray front to back, and then back to front, or side to side, the paint dust will settle on your surface and leave the finish rough and even sometimes mildly coarse. Also, paint the sides of your object first, for the same reasons..

Sanding

Sanding is the most time consuming and boring parts of the painting process.

When you are sanding, make sure it is as flat as possible. You don't want any roughness. You can tell if you did not sand properly if you can see dark spots or an "orange peel" like texture. Spend the most time with the high grit paper until it is as smooth as glass. Water should sheet right off it and leave a mirror finish.
Wet and Dry is more effect to get a mirror finish, it can be very time consuming using wet and dry dew to fines but will result is an awesome finish.

Achieving a mirror finish with spray cans

Resources sites
Painting Pointers - See painting Infomation on the left menu.

chewbucca · 23rd November 2004, 6:26 PM

1) Sand off the powdercoat with some 120-140 grit wet/dry sandpaper until its smooth (not down to the bare metal)

2) thin coat of Primer

3) Another coat of primer, bit thicker.

4) Sand with some 400 or so wet/dry sandpaper until smooth (dont sand to much, just enough to get any roughness out)

Now your ready for the actual spraypaint coats. My instructions are just what ive been doing - theyre not perfect. You can view my thread in the worklogs, i have some pics of what ive just been talkn about.

DDsD · 23rd November 2004, 9:12 PM

Thread stuck..

With any luck I (or Bluey) will be able to squish all the useful information the forum has generated into one BIG Sticky.. till then.. get used to the mess

Etacovda · 29th November 2004, 10:24 AM

This is a post of mine from another forum that I moderate, but its pretty applicable here. Theres probably glaring omissions and errors, but I did it late at night, so

Achieving a mirror finish with spray cans

Achieving a mirror finish with spray cans isnt easy; it takes a lot of work, but it can be done

If you have a good orbital sander, you're halfway there.

Equipment -

Sand Paper -

Grades - I use 180 through to 1500, wet and dry paper (its grey, and you can wet it as its wax paper backed)

Cleaning equipment -
Thinners is extremely helpful, but water works as long as you keep the surface contamination free (ie, no hands)

Primer -
A sandable primer - i use VHT sandable primer as it covers well and is very cheap at 9.99 a can. Other brands include plasticoat and duplicolor.

Base - Generally either a laquer or an enamel. Match the base coats to the clear.

Clear (optional) - Acrylic/laquer. Theres some good performance style ones - if you want to spend the money, go to a custom paint shop (the kind where they mix vehicle spray) and get some cans made up custom. The finish will almost always be better than store bought stuff.

Water
a non-residue based soap
Forced air heating device is handy if you have to work in colder weather (fan heater, hair dryer)
Car buffing compound is very handy
Sanding block
Wax
Cheese cloth - its basically cotton with lots of little holes in it.
Rags

First things first, take whatever is to be painted and do standard prep - remove everything from it etc. If youre painting the top of your case, you'll probably want to remove it too - if its riveted, you'll want to drill out the rivets. Take off the side panels, etc, and get them ready.

Sand everything back until it is dull with 180 grit paper, using the sanding block; wet or dry here, it doesnt really matter. Keep going until it is totally dull - it shouldnt take you too long. Keep some rags handy here, and wipe the surface down every once in a while and bang out your sand paper so you dont get deep scratching. Once its totally dull, clean it off with water and then wipe it down with a clean rag. Heating it here isnt a bad idea either, to remove the water more quickly.

Once this is done, get your primer (2 cans is always handy) and shake it up as per instructions on the can. Then lay the paint down on the surface. If you've never done this before, its a good practice to keep at least 40 cm away from the paint to avoid runs. Doing it with the work piece laid at a slight angle isnt a stupid idea either... place the panel down on the ground flat, and prop it up slightly with a piece of wood or whatever is handy that doesnt mind getting painted. This avoids runs, and still allows you to paint without having the can in a bad direction.

Once the primer is on flat, leave it for at least 20 minutes, but preferably a few hours. After this is done, get your 240/320/400 (up to 400 - i find that 320 is all thats neccessary really) grits of paper, and some soap water. Using a sanding block, sand from 320 through to 800 just as you did with the 180 - make sure its dull between and completely flat, make sure to wash down and wipe often. Once this is done, its onto the base coat (or colour coat). If you hit metal, repaint, and resand. Keep doing this until its flat.

When applying the base coat, its important to apply the right amount. Having a couple of incandesant or halogen bulbs around is handy, to put on the surface at different angles so you can accurately see by the reflection how much paint has been applied. Make sure your paint is even - I'm currently painting a case white, which is a bi*ch because its not obvious where ive been and where i havent - the lightbulb trick is helping me out here greatly.
Use the can instructions (sometimes theres leaflets on how to do it, or ask if you go to a custom shop) to paint - light strokes (two light coats is better than one heavy coat), pushing the paint away, from a distance. Generally 30cm. Try not to spray completely vertically - having the surface on an angle is good, because its easy to spray properly (being that spray cans dont like being horizontal) and the angle prevents serious running.

After this is done, break out the 400/600 grit sand paper, and wet sand the panel again, wiping down as per usual. Once this is done, another coat and another sand are required if the surface doesnt look even.

If its even looking, and you havent gone through to the primer, move to 1200 grit until its silk smooth. Clean down the surface with clean water, and dry.

Preheat the surface, then apply the clear coat.

Sand 800/1200 flat, then move to car buffing compound. Using cheese cloth for the compound is a VERY good idea, if you can find some. There are dish cloths with holes in them which should do a similar thing.

After all this is done, you should be able to see yourself in the side panel.
If you want to wax, it will protect the finish nicely.

Enjoy

Constructacon · 29th November 2004, 8:39 PM

When you have finished the coat of paint, turn the can upside down and spray for a few seconds until the the paint is out of the pick up system and nozzle. This prevents the nozzle clogging up with dry paint and making subsequent coats uneven or the nozzle spitting out large dollops of paint - ruining all your hard work.

BlueSmurf · 28th December 2004, 10:12 PM

Build a spraybooth to make sure you don't get dirt/dust on your job and overspray on everthing else.

This booth cost about $50 in wood, $15 in screws/hinges and $30 in plastic.

If you're really serious, add in the heatlamps/extractor fan. Breath easy, dry fast. Add another $100 for this and $27 for the silver slinky.

BlueSmurf.

Defyant · 21st January 2005, 9:36 AM

Heres my spray booth, an old converted bike shed 1 x ceiling fan (found in a bin) tape and plastic maybe 20 bux all up.

From this booth i got this job!

Can be seen here in pcdb worklog & entrys

http://forums.overclockers.com.au/sh...5&page=2&pp=15

Ronza · 22nd January 2005, 11:56 AM

Hmmm, seeking some advice on where to go on my spray painting from here. (Feel free to delete this after)

Its the fourth coat, Ive been sanding down in between each coat. Its pretty shiny but there are a couple of blobs and runs from previous coats are showing through, I can live with it but.....

Should I put the Clear Coat on now or Give it another Colour Coat or Sand it to 1500-Grit etc?

Defyant · 22nd January 2005, 5:52 PM

no need to sand between coats!
But, if you are sanding between coats how do you still have a run?

yes your on the right track tho, another coat of colour then clear,

i havnt used cans in a long time! the paint you see above is streight off the gun
no buffing chopping sanding, that would drive me nuts!!!

Etacovda · 26th January 2005, 6:10 AM

What compressor + gun do you have, and what specs do you recommend (ie pressure that the compressor can keep up with) - wanting to do spraying on a budget - v. nice paintjob btw

Harry72 · 8th February 2005, 2:24 AM

Blue smurf and Defyant, you two have been very lucky so far with your booths... your both using a extraction fan that is a non sealed motor, you are sucking highly explosive fumes through a electrical motor that has bare sparking contacts/bushes, Id advise buying a Xlotto ticket because you are very lucky to have not end up in a burns unit so far.
Do not use a non-sealed motor fan when spray painting... think about it, If you happen to breathe in some fume and the fan ignites an explosion your lungs will be singed, possibly causing your death, is your computer worth that much.
The same goes for all electrical gear in a spray booth, you can actually buy proper sealed switches/conduit/lights/fans, they cost heaps , and Im not even going to start telling you about EPA reg's...
Look up on the paint makers website and look up the MSDS for your paint.

BlueSmurf · 8th February 2005, 8:45 PM

Quote:

Originally Posted by Harry72

Look up on the paint makers website and look up the MSDS for your paint.

According to the MSDS I need a vapour concentration 35g/m3 for the hardener or 35g/m3 for the paint proper to reach the listed Explosion point.

While I have no doubt that the materials I'm using are flammable, there are a couple of mitigating factors.

- I'm using an airbrush.
- It doesn't even hold 35g of paint
- The booth is 3.8 m3
- The booth is not sealed

So even if I was able to instantly convert the contents of the airbrush to vapour, I'd be lucky to make 9.2g/m3 concentration (assuming a sealed booth).

I'm far more worried about the decrease in fertility and other nasty effects rather than the risk of explosion in these circumstances. If I was using a normal air gun, it'd be a different story.

BlueSmurf.

BlueSmurf · 9th February 2005, 8:11 PM

Guys,

I've merged discussion of Defyant's case to his worklog here:

http://forums.overclockers.com.au/sh...d.php?t=334935

Lets get back to spraypainting discussion.

BlueSmurf.

Defyant · 9th February 2005, 9:28 PM

ive already got a full work log posted there,delete it! its all pretty much explained in the worklog.

EDIT;
Cheers smurf ty

Harry72 · 11th February 2005, 4:49 PM

Expolsion point, is whats reached when heat is envolved... think of it this way, grab a can of flyspray flick a lighter in front of the spray stream what happens... it lights real easy doesnt it, but your in a big room. Your drawing the fume into an electrical appliance that has a several exposed arcing points.
You dont need to reach the quoted point. What they are saying this is when the fume reaches its most volatile concertration!
They have laws governing things like this for a reason.
Its your life, abeit maybe a short one... turn the fan off, or find a sealed motor.

23rd November 2004, 6:04 PM	#1
thrax Member Join Date: Aug 2002 Location: Brisbane Posts: 136	Spray Painting Tips Has anyone got any good tips when it comes to spray painting you're case with either a spray can or a spray gun + air-compressor. It’s been awhile since I’ve actual try to do this, and more so when I actual had done it was back in high school’s shop classes which seems like a lifetime ago . But I still remember a few fundamentals of what to do. Stand a fair distance way from the object to avoid spatting Take you’re time, no need to rush it Allow up to 30 mins for the applications to dry for an effect coat, lightly sand the applied area, and give it another light coat and repeat until satisfied. If anyone has an good suggestions I will be more than happy to update this thread with the information, more of less this will become a reference thread for those people interesting in give there cases or other objects a bit of face lift Things to do before painting You should be wearing proper painting attire, i.e. old shoes, shorts and shirt. Work in a well-ventilated area. I can't stress this enough. Cover near by objects. The over-spray will travel farther than you think. Rinse the objects you wish to paint, and dry them thoroughly. Make sure you wipe off ALL LINT, otherwise, you will just paint it to your surface, and leave a mark after you sand it out. Wear a protective mask. I use a wash cloth over my mouth and nose. Trust me, the headaches you get from not wearing it, are not worth it. You will learn to hate the smell of paint, guaranteed. Applying Your First Coat The primer should be a relatively thin layer of paint. It does not have to be perfectly smooth, so go briskly over the surface, don't go slowly like you would with the color and clear coat. If you use too much primer, it becomes gummy and UN-paintable. Always spray away from your. This forces and pushes the over-spray past the surface. If you spray front to back, and then back to front, or side to side, the paint dust will settle on your surface and leave the finish rough and even sometimes mildly coarse. Also, paint the sides of your object first, for the same reasons.. Sanding Sanding is the most time consuming and boring parts of the painting process. When you are sanding, make sure it is as flat as possible. You don't want any roughness. You can tell if you did not sand properly if you can see dark spots or an "orange peel" like texture. Spend the most time with the high grit paper until it is as smooth as glass. Water should sheet right off it and leave a mirror finish. Wet and Dry is more effect to get a mirror finish, it can be very time consuming using wet and dry dew to fines but will result is an awesome finish. Achieving a mirror finish with spray cans Resources sites Painting Pointers - See painting Infomation on the left menu. __________________ Intel Core 2 Quad Q6700 / Zalman CNP9700 NT \| EVGA 750i SLI \| BFG 8800 GTX \| 4x 1GB G.Skill F2-8500CL5-1GBHK DDR 2 (4096 MBytes) \| Windows Vista Ultimate 64 \| CPU-Z Report \| PC.DB Entry Last edited by thrax; 30th November 2004 at 5:28 AM.

23rd November 2004, 6:26 PM	#2
chewbucca Member Join Date: Jun 2003 Location: London Posts: 1,772	1) Sand off the powdercoat with some 120-140 grit wet/dry sandpaper until its smooth (not down to the bare metal) 2) thin coat of Primer 3) Another coat of primer, bit thicker. 4) Sand with some 400 or so wet/dry sandpaper until smooth (dont sand to much, just enough to get any roughness out) Now your ready for the actual spraypaint coats. My instructions are just what ive been doing - theyre not perfect. You can view my thread in the worklogs, i have some pics of what ive just been talkn about. __________________ Bobby Fischer: "I like the moment when I break a man's ego."

29th November 2004, 10:24 AM	#4
Etacovda Member Join Date: Jun 2003 Location: Dunedin, New Zealand Posts: 511	This is a post of mine from another forum that I moderate, but its pretty applicable here. Theres probably glaring omissions and errors, but I did it late at night, so Achieving a mirror finish with spray cans Achieving a mirror finish with spray cans isnt easy; it takes a lot of work, but it can be done If you have a good orbital sander, you're halfway there. Equipment - Sand Paper - Grades - I use 180 through to 1500, wet and dry paper (its grey, and you can wet it as its wax paper backed) Cleaning equipment - Thinners is extremely helpful, but water works as long as you keep the surface contamination free (ie, no hands) Primer - A sandable primer - i use VHT sandable primer as it covers well and is very cheap at 9.99 a can. Other brands include plasticoat and duplicolor. Base - Generally either a laquer or an enamel. Match the base coats to the clear. Clear (optional) - Acrylic/laquer. Theres some good performance style ones - if you want to spend the money, go to a custom paint shop (the kind where they mix vehicle spray) and get some cans made up custom. The finish will almost always be better than store bought stuff. Water a non-residue based soap Forced air heating device is handy if you have to work in colder weather (fan heater, hair dryer) Car buffing compound is very handy Sanding block Wax Cheese cloth - its basically cotton with lots of little holes in it. Rags First things first, take whatever is to be painted and do standard prep - remove everything from it etc. If youre painting the top of your case, you'll probably want to remove it too - if its riveted, you'll want to drill out the rivets. Take off the side panels, etc, and get them ready. Sand everything back until it is dull with 180 grit paper, using the sanding block; wet or dry here, it doesnt really matter. Keep going until it is totally dull - it shouldnt take you too long. Keep some rags handy here, and wipe the surface down every once in a while and bang out your sand paper so you dont get deep scratching. Once its totally dull, clean it off with water and then wipe it down with a clean rag. Heating it here isnt a bad idea either, to remove the water more quickly. Once this is done, get your primer (2 cans is always handy) and shake it up as per instructions on the can. Then lay the paint down on the surface. If you've never done this before, its a good practice to keep at least 40 cm away from the paint to avoid runs. Doing it with the work piece laid at a slight angle isnt a stupid idea either... place the panel down on the ground flat, and prop it up slightly with a piece of wood or whatever is handy that doesnt mind getting painted. This avoids runs, and still allows you to paint without having the can in a bad direction. Once the primer is on flat, leave it for at least 20 minutes, but preferably a few hours. After this is done, get your 240/320/400 (up to 400 - i find that 320 is all thats neccessary really) grits of paper, and some soap water. Using a sanding block, sand from 320 through to 800 just as you did with the 180 - make sure its dull between and completely flat, make sure to wash down and wipe often. Once this is done, its onto the base coat (or colour coat). If you hit metal, repaint, and resand. Keep doing this until its flat. When applying the base coat, its important to apply the right amount. Having a couple of incandesant or halogen bulbs around is handy, to put on the surface at different angles so you can accurately see by the reflection how much paint has been applied. Make sure your paint is even - I'm currently painting a case white, which is a bich because its not obvious where ive been and where i havent - the lightbulb trick is helping me out here greatly. Use the can instructions (sometimes theres leaflets on how to do it, or ask if you go to a custom shop) to paint - light strokes (two light coats is better than one heavy coat), pushing the paint away, from a distance. Generally 30cm. Try not to spray completely vertically - having the surface on an angle is good, because its easy to spray properly (being that spray cans dont like being horizontal) and the angle prevents serious running. After this is done, break out the 400/600 grit sand paper, and wet sand the panel again, wiping down as per usual. Once this is done, another coat and another sand are required if the surface doesnt look even. If its even looking, and you havent gone through to the primer, move to 1200 grit until its silk smooth. Clean down the surface with clean water, and dry. Preheat the surface, then apply the clear coat. Sand 800/1200 flat, then move to car buffing compound. Using cheese cloth for the compound is a VERY good idea, if you can find some. There are dish cloths with holes in them which should do a similar thing. After all this is done, you should be able to see yourself in the side panel. If you want to wax, it will protect the finish nicely. Enjoy Last edited by Etacovda; 16th April 2005 at 8:45 PM.*

29th November 2004, 8:39 PM	#5
Constructacon Member Join Date: Nov 2004 Location: Brisbane, QLD Posts: 209	When you have finished the coat of paint, turn the can upside down and spray for a few seconds until the the paint is out of the pick up system and nozzle. This prevents the nozzle clogging up with dry paint and making subsequent coats uneven or the nozzle spitting out large dollops of paint - ruining all your hard work. __________________ MAME Over - Custom built arcade cabinet This season's mod - The New Black Previous work - Got Milk?

28th December 2004, 10:12 PM	#6
BlueSmurf Dream it. Build it. Join Date: Aug 2001 Location: Baldivis, WA Posts: 2,398	Build a spraybooth to make sure you don't get dirt/dust on your job and overspray on everthing else. This booth cost about $50 in wood, $15 in screws/hinges and $30 in plastic. If you're really serious, add in the heatlamps/extractor fan. Breath easy, dry fast. Add another $100 for this and $27 for the silver slinky. BlueSmurf. Last edited by BlueSmurf; 28th December 2004 at 10:29 PM.

21st January 2005, 9:36 AM	#7
Defyant Member Join Date: Mar 2004 Location: Sydney, Bardwell Park Posts: 902	Heres my spray booth, an old converted bike shed 1 x ceiling fan (found in a bin) tape and plastic maybe 20 bux all up. From this booth i got this job! Can be seen here in pcdb worklog & entrys http://forums.overclockers.com.au/sh...5&page=2&pp=15 __________________ Don't "Just Cross that bridge when you get to it" , *Mod it!* Never argue with an idiot. They will drag you down to their level and beat you with experience! Last edited by Defyant; 9th February 2005 at 9:37 PM.

22nd January 2005, 11:56 AM	#8
Ronza Member Join Date: Aug 2004 Posts: 3,159	Hmmm, seeking some advice on where to go on my spray painting from here. (Feel free to delete this after) Its the fourth coat, Ive been sanding down in between each coat. Its pretty shiny but there are a couple of blobs and runs from previous coats are showing through, I can live with it but..... Should I put the Clear Coat on now or Give it another Colour Coat or Sand it to 1500-Grit etc?

22nd January 2005, 5:52 PM	#9
Defyant Member Join Date: Mar 2004 Location: Sydney, Bardwell Park Posts: 902	no need to sand between coats! But, if you are sanding between coats how do you still have a run? yes your on the right track tho, another coat of colour then clear, i havnt used cans in a long time! the paint you see above is streight off the gun no buffing chopping sanding, that would drive me nuts!!! __________________ Don't "Just Cross that bridge when you get to it" , *Mod it!* Never argue with an idiot. They will drag you down to their level and beat you with experience!

26th January 2005, 6:10 AM	#10
Etacovda Member Join Date: Jun 2003 Location: Dunedin, New Zealand Posts: 511	What compressor + gun do you have, and what specs do you recommend (ie pressure that the compressor can keep up with) - wanting to do spraying on a budget - v. nice paintjob btw

8th February 2005, 2:24 AM	#11
Harry72 Member Join Date: Feb 2005 Location: planet earth Posts: 9	Blue smurf and Defyant, you two have been very lucky so far with your booths... your both using a extraction fan that is a non sealed motor, you are sucking highly explosive fumes through a electrical motor that has bare sparking contacts/bushes, Id advise buying a Xlotto ticket because you are very lucky to have not end up in a burns unit so far. Do not use a non-sealed motor fan when spray painting... think about it, If you happen to breathe in some fume and the fan ignites an explosion your lungs will be singed, possibly causing your death, is your computer worth that much. The same goes for all electrical gear in a spray booth, you can actually buy proper sealed switches/conduit/lights/fans, they cost heaps , and Im not even going to start telling you about EPA reg's... Look up on the paint makers website and look up the MSDS for your paint.

9th February 2005, 8:11 PM	#13
BlueSmurf Dream it. Build it. Join Date: Aug 2001 Location: Baldivis, WA Posts: 2,398	Guys, I've merged discussion of Defyant's case to his worklog here: http://forums.overclockers.com.au/sh...d.php?t=334935 Lets get back to spraypainting discussion. BlueSmurf. Last edited by BlueSmurf; 9th February 2005 at 9:36 PM. Reason: Merged thread when discovered worklog exists

9th February 2005, 9:28 PM	#14
Defyant Member Join Date: Mar 2004 Location: Sydney, Bardwell Park Posts: 902	ive already got a full work log posted there,delete it! its all pretty much explained in the worklog. EDIT; Cheers smurf ty __________________ Don't "Just Cross that bridge when you get to it" , *Mod it!* Never argue with an idiot. They will drag you down to their level and beat you with experience! Last edited by Defyant; 9th February 2005 at 9:39 PM.

11th February 2005, 4:49 PM	#15
Harry72 Member Join Date: Feb 2005 Location: planet earth Posts: 9	Expolsion point, is whats reached when heat is envolved... think of it this way, grab a can of flyspray flick a lighter in front of the spray stream what happens... it lights real easy doesnt it, but your in a big room. Your drawing the fume into an electrical appliance that has a several exposed arcing points. You dont need to reach the quoted point. What they are saying this is when the fume reaches its most volatile concertration! They have laws governing things like this for a reason. Its your life, abeit maybe a short one... turn the fan off, or find a sealed motor.