Cracks in gloss

[Jacko74]

Further to my recent post regarding glossing my garage door black.

Job done, all looked lovely for a week or so.

As can be seen from the photos, cracks have started to appear.
Previous cracks were here, but I filled over them > sanded back > 2 x undercoat > 2 x gloss.
What Have I done wrong? Or indeed, what can I do to stop it coming back again?

I used dulux weathershield u/c (water-based). Would it of been better to use a (thicker) oil based u/c?

Thanks in advance

Untitled

• Jacko74
• 20 Oct 2011
• 1

 

[Robbie uk]

Why have you used water based under coat outside? ... and i can hear several people saying about moving out of the dark ages..etc.. but you cant beat oil based undercoat outside. I dont believe that the water based undercoats made today are able to withstand the expansion and contraction of a black door in the sun. Having cracks there in the first place wont have helped. Sometimes better to strip it back and start again.
I know weathershield is a cracking paint but would have used their oil based undercoat and gloss system.

 

[Jacko74]

Why have you used water based under coat outside?

Simple really.
Because the can says EXTERIOR undercoat.

 

[elrobbo82]

what filler did you use?

 

[TheDec]

Looking at that pic there seem to be other areas apart from the obvious cracks that really dont appear to be looking very healthy, apart from sanding back the filler what other prep did you do.

Dec

 

[joe-90]

I know weathershield is a cracking paint

Say no more.

 

[Jacko74]

RE: Prep work:
The whole door was rubbed flat with 120 paper, 240 paper on beading.
Filled where needed with Metolux 2part wood filler.
Sanded filler with 120 then 240.
Dusted off with meths/rag.

Apart from the cracks, the door is like a mirror.
White specks showing up in the picture are just dust on the paint.

 

[sparkwright]

If the cracks were there before possibly this is due to poor preparation before painting the door the time before - if that makes sense.

 

[Jacko74]

If the cracks were there before possibly this is due to poor preparation before painting the door the time before - if that makes sense.

Couldnt agree more.
When I did the door from new, I did no research, just slapped on Ronseal 5 year woodstain.

All I'm after now is a way of stopping the splits appearing again and again.

 

[Robbie uk]

Jacko, i wasnt trying to be sarcastic. Water based undercoat just doesnt cut it outside. I dont care what anyone sasy it just wont move with the timber like oil based undercoat will. Its too hard and wont penetrate the wood anyway. Just because it says it on the tin doesnt mean it will do it. Its trial and error with most things and i have tried most things in the last 30 odd years of painting.

 

[Jacko74]

So sand back, fill, sand, 2 x oil-based u/c, gloss.

Ignore me snapping Robbie, must have my period this week.

Cheers.

 

[joe-90]

You can get exterior undercoat that is extra stretchy. Dulux and even Wilkos do one.