The Spray Painting Thread

[pac]

If your using basecote system it will be flat when dry but then has to have a clear cote for gloss

[o_man_ra23]

I wasn't talking about the needle. At the top of the pot, there is a breather hole. This MUST be 100% clear. It often gets dried up paint in it as it gets neglected all too often during cleaning.

[Gibbon]

I wasn't talking about the needle. At the top of the pot, there is a breather hole. This MUST be 100% clear. It often gets dried up paint in it as it gets neglected all too often during cleaning.

Yup - I clean that every time I clean the gun as well. It's all clear.

[ian]

what is the brand of paint
ian

["Z" UTE]

Yes - using the 1.4mm tip.

Results of the first coat - the camera isn't really capturing the white color correctly.

It's like a real chalk white. It hasn't got any gloss to it - sounds like I wasn't mixing it correctly. Just been putting the paint and the thinners into the gun pot and mixing until it's even. whoops.

The paint dude said I wouldn't need to use any clear

Air pressure at the compressor 45 -50 psi, with 9 metres of hose, good clean gun, you should have gloss. If your air pressure is too high, the paint will be really rough and chalky when dry.

Try my method of mixing, and lay on a heavier coat, overlap the that coat by 50% with the next, and so on.

cheers Chuck.

[Gibbon]

Ah - much better now.



The camera is not showing how white the paint is - but here's a piccy trying to show the sun shining off the roof.

Should come up nicely after the first rub back.

How long should I leave it before starting to rub it back?

["Z" UTE]

Ah - much better now.

Should come up nicely after the first rub back.

How long should I leave it before starting to rub it back?

Looking good mate, with acrylic, I would leave it for 3 days before colour sanding. Park it in the sun in the middle of the day, for a couple of days, the UV helps to cure the paint.

When cured, run your hands over the paint and feel for any bits of lumps of stuff trapped in the paint. Grab some 1500wet and dry that has benn soaked in warm water and detergent for 20 minutes. I use a block of wood about the size of a matchbox and wrap the 1500 around that. Give all the lumpy bits a quick knock down, then switch to 2000 wet and dry that has had a similar soaking. Again use the little block, and do about a square foot at a time. For the curves and edges, use a flexible piece of rubber about 15mm thick. NEVER rub paralell with the swage lines or edges, always criss cross these areas at a 45deg angle.

When finished with the 2000, grab some 3000, available only at paint shops, and repeat the rub down. At this stage you should have no orange peel, and a perfectly flat surface, ready for compound buffing. I have recently used a compound called "JUICE" available from Allards Paint in Fyshwick, the stuff is amazing. Use a very soft black foam pad, and remember to work a small section at a time. Buff edges with the pad rotating off that edge, going the opposite way will tear the pad and your paint.

cheers Chuck.

[Gibbon]

Awesome - I can sit around for 3 days watching paint dry

Will I need to do a coats of clear to get a full gloss?

Cheers for the advice so far.

[briggsy]

Ah - much better now.



The camera is not showing how white the paint is - but here's a piccy trying to show the sun shining off the roof.

Should come up nicely after the first rub back.

How long should I leave it before starting to rub it back?

did you put sealer around the rust repairs?

["Z" UTE]

Awesome - I can sit around for 3 days watching paint dry

Will I need to do a coats of clear to get a full gloss?

Cheers for the advice so far.

From your previous posts, I thought the paint was a topcoat colour. If so, no clear required. If it is a basecoat colour, then you will need to clearcoat. Sand the colour coat with 800 wet and dry, or scuff with the painters red scotchbrite pad, then apply 2 -3 coats of clear at the recommended thinning ratio, and a final coat with 10-20% clear the rest thinners. This last coat really brings up the gloss.

A clear coat is normaly applied as soon as the last colour coat has "flashed off". Leave it for any more than a couple of hours, then you have to scuff the surface, as though starting from scratch.

cheers Chuck.

[hamgatan]

define "flashed off"

ive noticed recently if i shoot clear about an hour after the last colour coat goes on, when the clear cures it has millions of tiny microscopic bubbles in it..

if i leave the colour to dry overnight lets say.. then i come back next day and shoot clear, i get an overall ok finish, but some areas still develop the same microscopic bubbles.

thinking it was my compressor setup.. i tried the same process again on a test bumper, but with pressure pack this time.. same results... bubbles...

[twentyEight]

Flash Off is the term used to describe the solvent (thinners) evaporating.

The problem you're describing is Pinholing or Solvent Popping.

This happens when the thinners has too fast a flash off period for the ambient temperature. In Winter you should use a Fast Thinner, in Summer a Slow Thinner, in between use a Medium Thinner. (Pinholing can also be caused by insufficient flash time in between coats, or the application of coats too heavy.)

You cant repair the problem. You will need to sand down the finish and repaint it. Use a slower thinner. (Wait longer in between coats, or apply less material, if these are determined to be the cause.)

[tomvale13]

Looking good mate, with acrylic, I would leave it for 3 days before colour sanding. Park it in the sun in the middle of the day, for a couple of days, the UV helps to cure the paint.

When cured, run your hands over the paint and feel for any bits of lumps of stuff trapped in the paint. Grab some 1500wet and dry that has benn soaked in warm water and detergent for 20 minutes. I use a block of wood about the size of a matchbox and wrap the 1500 around that. Give all the lumpy bits a quick knock down, then switch to 2000 wet and dry that has had a similar soaking. Again use the little block, and do about a square foot at a time. For the curves and edges, use a flexible piece of rubber about 15mm thick. NEVER rub paralell with the swage lines or edges, always criss cross these areas at a 45deg angle.

When finished with the 2000, grab some 3000, available only at paint shops, and repeat the rub down. At this stage you should have no orange peel, and a perfectly flat surface, ready for compound buffing. I have recently used a compound called "JUICE" available from Allards Paint in Fyshwick, the stuff is amazing. Use a very soft black foam pad, and remember to work a small section at a time. Buff edges with the pad rotating off that edge, going the opposite way will tear the pad and your paint.

cheers Chuck.

awesome post, we're doing acrylic as well (white) and this is gold.



Thanks Chuck.

["Z" UTE]

define "flashed off"

ive noticed recently if i shoot clear about an hour after the last colour coat goes on, when the clear cures it has millions of tiny microscopic bubbles in it..

if i leave the colour to dry overnight lets say.. then i come back next day and shoot clear, i get an overall ok finish, but some areas still develop the same microscopic bubbles.

thinking it was my compressor setup.. i tried the same process again on a test bumper, but with pressure pack this time.. same results... bubbles...

Flash off can best be described as a visible drop off, of the wet look of the paint, this is used as an indicator that the paint solvents have evaporated sufficiently for you to apply another coat.

If you do not wait long enough, the next coat of paint will tend toward runs and sags. Leave it too long between coats, and the various layers will have a semi cured layer on top of each them, forming a semi porous barrier, effectively sealing in some of the solvents in those individual layers.

So you either observe flash off time between coats and keep applying paint and clear, (this is generally known as wet on wet) or you do one coat, let it dry completely, sand that coat, paint again, let it dry again, sand again, and on you go. The sanding between the dry coats is to roughen the surface, to allow the next coat to bond to the previous. The wet on wet allows the build up of a uniformly wet paint film, which will dry as a single layer.

In a garage paint job, the fast thinners is used in cooler conditions, as the evaporation rate is perfect for those temps.

The slow thinners is used in hotter temps, to give the paint a chance to flow out (this is what helps the paint to lay flat on the panel with minimal orange peel) before the thinners evaprates totally.

cheers Chuck.

[Z2TT]

Hi guys,

I need to touch up a section of my rear 1/4 panel, I accidentally got it down to the primer when buffing it as there had been little paint left before the primer on one section.

So it's white in colour and I'll be working with acrylic lacquer paint. How should I go about blending it in once I have sprayed on some paint? What sort of sandpaper should I use and which a block or just by itself?

Any other tips on blend ins?