DIY Forum

 

Ultimate HandymanUltimate Handyman on Pinterest

 

DIY Forum/Home improvement advice forum

 

 

A-Z CONTENTS | DISCLAIMER | DIY VIDEO | HOME | SAFETY FIRST | FORUM RULES

It is currently Fri Apr 19, 2019 9:35 am


Time zone: Europe/London [ DST ]




 

 


Post new topic Reply to topic  [ 9 posts ] 
Author Message
PostPosted: Fri Sep 21, 2018 11:13 pm 
Online
Newly registered Member

Joined: Thu Feb 08, 2018 9:25 pm
Posts: 25
Has thanked: 1 times
Been thanked: 5 times
Last time I painted a window sill I burnt off all the old paint to bare wood. Sanded it down smooth. Painted with Dulux Trade quick dry undercoat. Followed by 2 coats of Dulux Trade quick dry gloss PBW. It may have been 3 in the end, can't remember.

However the finish wasn't smooth. You could see the grain was raised and was bumpy to touch.

Does this happen because the paints are water based and the wood is soaking up the moisture?

I'm going to be doing another window sill and would like this to have a better finish. What did I do wrong?

Do I need to apply 1 coat of undercoat then sand until smooth and apply a second undercoat?

Thanks in advance
AnthonyImage

Sent from my XT1580 using Tapatalk


Share on FacebookShare on TwitterShare on DiggShare on Delicious
Top
 Profile  
Reply with quote  
PostPosted: Sat Sep 22, 2018 8:31 am 
Offline
Senior Member

Joined: Wed Feb 26, 2014 9:35 pm
Posts: 3522
Has thanked: 45 times
Been thanked: 747 times
Probably a combo of not sanding smooth enough in the first place, then lack of sanding between coats of paint causing the grain to raise.


Top
 Profile  
Reply with quote  
PostPosted: Sat Sep 22, 2018 9:49 am 
Offline
Senior Member

Joined: Thu Apr 14, 2011 7:33 pm
Posts: 4140
Location: Dundee, Scotland.
Has thanked: 786 times
Been thanked: 884 times
:withstupid:

There are lines from the window towards where you are standing for the photo. Are those lines something you can feel with your finger tips or some trick of the photograph with light? If you can feel them certainly more sanding.

Water based paint will raise the grain more than solvent based paints, and you need to sand before the next coat using something like 300ish grade paper and then make sure the surface is perfectly clean (use a tack cloth). The raising of the grain is tiny little spots of wood lifting ... it is not "bumpy".

You should have used Primer, Undercoat, Top coat ... I think you missed the primer but this has got nothing to do with the problem you describe.

Finally, did you stir the paint well? And did you let each coat dry as much as possible, i.e. more than the tin says for recoating time? The opacity does not look any good either.


Top
 Profile  
Reply with quote  
PostPosted: Sat Sep 22, 2018 10:27 am 
Offline
Senior Member

Joined: Wed Feb 26, 2014 9:35 pm
Posts: 3522
Has thanked: 45 times
Been thanked: 747 times
Something else that can be a problem (and very hard to solve) with painting softwoods is that when moistened the softer grain raises quickly but takes a while to dry out, whereas the harder grain absorbs moisture more slowly and doesn't raise as much.

What ends up happening is the soft grain plumps up, you sand things smooth and level and over time the soft grain dries out and sinks back down which is now below the level of the harder grain leaving you with an uneven surface. Trying to sand this smooth can be a real pain as the harder grain resists the sandpaper and if you use a sanding surface that is too soft you end up just digging out the softer grain even more.


Top
 Profile  
Reply with quote  
PostPosted: Sat Sep 22, 2018 11:37 am 
Online
Newly registered Member

Joined: Thu Feb 08, 2018 9:25 pm
Posts: 25
Has thanked: 1 times
Been thanked: 5 times
Ok,I didn't sand between coats. By the sounds of it that's where I've gone wrong.

The sill was perfectly smooth before undercoat. And it was a couple of days between coats.

I have some zinsser bin. Should I use this as a primer before the undercoat? Or some other primer?

So would this be correct?
1 primer
2 undercoat
3 sand with 300 then first coat
4 sand with 300 then second coat

The vertical thin lines are from my mobile. It didn't like the led torch I was using.

Thanks
Anthony

Sent from my XT1580 using Tapatalk


Top
 Profile  
Reply with quote  
PostPosted: Sat Sep 22, 2018 11:53 am 
Online
Newly registered Member

Joined: Thu Feb 08, 2018 9:25 pm
Posts: 25
Has thanked: 1 times
Been thanked: 5 times
I've just done a Google for primer.

Would dulux trade quick dry wood primer undercoat be a better option than using the zinser?

Would I need to sand after applying this primer undercoat?

Thanks

Sent from my XT1580 using Tapatalk


Top
 Profile  
Reply with quote  
PostPosted: Sat Sep 22, 2018 2:39 pm 
Offline
Senior Member

Joined: Thu Apr 14, 2011 7:33 pm
Posts: 4140
Location: Dundee, Scotland.
Has thanked: 786 times
Been thanked: 884 times
Yes use the Dulux stuff. You need primer or primer/undercoat if you have bare wood.

You need something thicker for the first sanding of the wood ... after you finish scraping. 120grade followed by 180 ??? (a lot depends how much sanding is needed and how heavy handed you are). You are better off using a sanding block example when doing the first sanding.
These are example for in between coats papers http://www.oakey-abrasive.co.uk/products/between-coats/ B&Poo used to do a pack with a selection of sheets but I have no idea what it has now.

Whether you need to sand in between every coat or not. Raised grain feels like 1 or 2 days growth of whiskers/beard, and if you are a woman all I can suggest is go around and run the back of your fingers at random blokes' faces. You will soon get the idea of what scrapes your skin and what doesn't. If the wood feels rough, sand in between coats and clean afterwards.

You only have to remove the sticky out bits not be heavy handed.



For this message the author OchAye has received gratitude : demusss
Top
 Profile  
Reply with quote  
PostPosted: Sat Sep 22, 2018 5:06 pm 
Online
Newly registered Member

Joined: Thu Feb 08, 2018 9:25 pm
Posts: 25
Has thanked: 1 times
Been thanked: 5 times
Brilliant thanks for the advice.

Guys will look at me daft if I start feeling up their stubble :)

Anthony

Sent from my XT1580 using Tapatalk



For this message the author demusss has received gratitude : OchAye
Top
 Profile  
Reply with quote  
PostPosted: Sat Sep 22, 2018 6:57 pm 
Offline
Senior Member

Joined: Thu Apr 14, 2011 7:33 pm
Posts: 4140
Location: Dundee, Scotland.
Has thanked: 786 times
Been thanked: 884 times
demusss wrote:
Guys will look at me daft if I start feeling up their stubble :)
You might look equally daft if you use the back of your hand to "feel" the wood and then feel your face, sand and repeat.

BTW. It was damn hard at my working life to try and learn not to assume gender. Often still is ::b

PS. Unfortunately the brush aficionados are not posting any more. We told each other stories of brushing "gently" our lips with new brushes (in the bathroom) and then practicing dry cutting in on the inside of the bathroom door.


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 9 posts ] 

 

 




Similar topics
   

Time zone: Europe/London [ DST ]


Who is online

Users browsing this forum: No registered users and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Visit Solent plastics


 

 

 

News News Site map Site map SitemapIndex SitemapIndex RSS Feed RSS Feed Channel list Channel list
ultimatehandyman privacy policy

Contact

 

Powered by phpBB® Forum Software © phpBB Group

phpBB SEO