Paint Your Wagon - with a roller!

[HarryMann]

Was it a fresh roller and tray?

[RobMS88]

As the sheets of metal were plain, mild steel, I did not key them up. Opps. I know you definitely do this for the wagon / car, but I assumed the paint would be OK for the sheets of metal if all I did was clean them up with white spirit. I rubbed them down several times with a cloth, hard, until no dirt came off them any more - then let them dry.

It was a fresh roller and tray.

Here are two links to photos of the result I got after one coat of paint on the sheets. I am not sure whether the contamination came from the roller, sheet, paint or what, but next time I will definitely clean everything a lot more and key up the sheet. It might just be imperfections in the steel. Don't particularly want this when I take the plunge with the real thing.

Speculations welcome.

http://i384.photobucket.com/albums/oo28 ... C00008.jpg" onclick="window.open(this.href);return false;
http://i384.photobucket.com/albums/oo28 ... C00009.jpg" onclick="window.open(this.href);return false;

Cheers

[HarryMann]

Definitely particles and not bubbles?
Image loses definition when zoomed so makes it difficult.

Can you not pick a particle out of the surface and examine it?
Did you not see anything on the roller?
Did you put the roller down on anything other than the tray at any time?
Could anything have blown or dropped into the tray, say from the paint tin lid?
Was the steel rusty to start with?

...have you got good closeup eyesight?

[ermie571]

my two penneth on this....

You didn't have your roller fully saturated before you applied to the metal. It looks like the dried air bubbles I got the first time I attempted this. Also....bits of dust etc from your roller?

To get rid of the air bubbles I would go over very very very lightly.....this reduced to the orange peel effect spoken of earlier.

regards

[RobMS88]

Unfortunately, I do not have a better camera, so I cannot get one that zooms better.

I only painted it a day ago, so I am going to let it harden up for a while before I scrape a piece out to see what it is.

I will update if I come to any conclusions. I will eventually wet and dry it back and see if it comes out. Hey ho.

I appreciate the input with places to look for errors I may have made.

Rob

[HarryMann]

Yes Emma air bubbles
They look a bit moon shaped as if some have popped...

Rob how much thinning did you give it?

The best period for final rollering seems to be between the roller skidding to start with and later when it starts pulling the paint back off...
unless you are rolling out runs when even late doors it's still worth it with a dryish roller to save a lot of flatting thick wet runs.

[RobMS88]

I kinda guessed on the thinning for the roller. I do not know for sure how much, but it took about 4 seconds for it to drip from the stiring stick.

I used a paint brush before the roller and thinned the brush paint by ~18%. By that I mean 2 parts thinner to 9 parts paint. For example, total volume, if each part is 10ml, equals 110ml.

110ml x 18.18% = 19.99ml (or 20ml of thinner).

I know this can get confusing as some people thin with a different formular. For example, thining by 10%, some might do 10 parts paint to 1 thinner, whereas others do 9 parts paint to 1 thinner to express they have thinned by 10%. I guess whatever works for you is good by my book.

The roller I definitely thinned by more than this. It was probably in the realms of 25%, i.e 3 parts paint to 1 part thinner. It rolled OK, but there was loads of bubbles. Another way of looking at it is that I rolled with the steel panel verticle to see if it ran so that when I come to do the real thing, I know it won't run. It didn't run at all. It wasn't like near water consistency. Not thinned that much.

I just sanded down the panel I did by brush and the "grit" that was left by the brush was less than the roller, and it came off with 600 grade wet and dry. I am holding out hope it will do the same with the roller panel when I come to do that as well.

[HarryMann]

I know what you mean by different interpretations of say a 25% thinning.
The relationship you are using gives a greater thinning.. 1:3 is a lot!

Last night I knocked some paint up and added about 1:9 or 1:10 - notice that the absolute error between the two interpretations diminishes as the % drops!
Went on lovely by the way..normal problem though run out of light or paint or both as I'm finishing


Rawlinsons paints once told me that above 10% thinning starts to diminish the paint's inherent properties. .. read what you like into that.

I understood originally that the 25% figure is more for spraying than brushing or rollering.

Hopefully Ralph & others with a lot more experience will comment.

[baaaron]

Hi guys,

finally I will start painting my van tomorrow! Now I hope someone can quickly answer me the following question regarding masking:
I`m doing a two colour painting (RAL 5010 blue + RAL9010 white). As the opacity of blue is obviously better than white I will first start with white following blue (on the picture white will be fresh white and yellow will be blue):
https://www.dropbox.com/s/uex8je6h7uieo ... 1%2046.jpg

Now how long should I wait until I can mask the white parts for starting with blue? Time is unfortunately limited and I`d like to do the van on sat/sun but my fear is that the colour will come off when removing the masking on the new white color

I`m using the 3M Scotch masking tape:
http://www.amazon.co.uk/dp/B004L9XBDO

Any suggestions?

thanks & regards

[RobMS88]

Hello, Baaaron

You might want to wait for someone with real life experience as I can only inform you based upon what I have read. Although you may have already read it, too.

I have seen posts where people say that you need to wait at least 3-4 weeks for the paint to really cure. With that in mind, my advice, if I was in your shoes, would be wait as long as possible to give myself the best chance with the masking.

It might be possible, if the white paint did come off, to go back over the white paint with a high grade wet and dry paper to smooth it out again, then buff back to a shine? Again, if I was in your shoes, I would put at least 4 coats of paint on and / or try it out on an old piece of metal first; paint it up, mask the old piece of metal and see what happens.

Regards

Rob

[PeeSG]

Hi all,

If you're going to paint your van, please do it responsibly, my van was roller painted and the paint is stretched, wrinkled, peely and different colours. This is what i have to deal with now - i did pay a good price and am not complaining, but this is just an insight into what can happen, and for a better finish, you might consider investing in a HVLP spraying kit. This was all peeled off by hand as easy as wet wallpaper.

[HarryMann]

By good price you mean ? Cheap?

'Stretched' not quite understand how paint can be stretched.
Anyhow, sounds fundamentally very bad or zero prep and a rather slapdash approach.

I don't think roller painting is suited to a commercial service, due to its very nature, much better matched to DIY and a steady Eddy unrushed piecemeal approach.

[HarryMann]

Images have just rendered. . Looks like it wasn't even washed and degreased before painting let alone thoroughly flatted back.
How many coats did you pay for?

[PeeSG]

I think you are getting the wrong idea, i bought the van and it was aleady done, just showing that it needs to be done properly no matter how anal it sounds. I would never pay for my van to be done! especially not rollered.

I have seen some guys on youtube form america doing a demo of the rollering and buffing, it looks amazing, but i dont think its the same over here.

By stretched, i mean that it has shrunk back and pulled itself out of the corners etc. i dont know who did it, but it looked alright from a distance, but up close it was rough as. Here it was.



As for HVLP, you can get a turbine setup from ebay for as little as £200 and spray the whole lot. obvioulsy plus paint costs.

[HarryMann]

Sorry! A good price for the van, yes... and had obviously a quick one-two with the roller. Probably straight over the last coat of wax (as in waxed 10 years before... and never washed)

I wonder what makes it shrink back.. applied very hot or very cold, maybe too much thinning or not enough