Smoothing out wood grain

[cliveb]

We have a bay window, and the top face of the internal sill is painted plywood with a very obvious grain showing through which I'd like to smooth out. Presumably wood grain filler will work, but wondering if there's a less labour intensive option. Has anyone used Polycell Crack Free paint? I realise it's intended for ceilings, but do you think it would fill in the grain? And can you apply it on top of existing gloss (after keying with coarse sandpaper)? Any other suggestions?

 

[BrianM]

I’d change the sill out and use MDF if you’re just going to paint it, not sure why the carpenter would have used plywood in the first place….

 

[cliveb]

I’d change the sill out and use MDF if you’re just going to paint it, not sure why the carpenter would have used plywood in the first place….

Thanks, but that's not an option, given that we had new windows installed recently which have trim on top of the plywood that I don't want to disturb.
So using some kind of filler remains my only option.

Have also considered vinyl wrap, but suspect the grain will show through.

 

[GreiginFife]

We have a bay window, and the top face of the internal sill is painted plywood with a very obvious grain showing through which I'd like to smooth out. Presumably wood grain filler will work, but wondering if there's a less labour intensive option. Has anyone used Polycell Crack Free paint? I realise it's intended for ceilings, but do you think it would fill in the grain? And can you apply it on top of existing gloss (after keying with coarse sandpaper)? Any other suggestions?

I wouldn't use the filler paint, as the plywood will absorb all of it's moisture and it will just crack and end up a god awful mess. Plywood shouldn't have too much grain showing on it's surface unless it's been affected by moisture at some point (or just poor quality ply).

When it comes to wood though, and if it's quite bad, I'd skip the quick fixes and just get the filler out (a decent wood filler with lower water content), sand the surface then fill, sand again and then paint.

In my experience a rushed or shortcut finish on any wooden surface will look like a rushed or shortcut finish. You'll probably end up doing it twice at double the effort.

A second option, and one that seems to be more and more popular in the furniture world, is covering it with either a plain, coloured or patterned melamine sheet. Not for me, personally, but seen a lot of bench tops being covered in it.

 

[cliveb]

I wouldn't use the filler paint, as the plywood will absorb all of it's moisture and it will just crack and end up a god awful mess. Plywood shouldn't have too much grain showing on it's surface unless it's been affected by moisture at some point (or just poor quality ply).

When it comes to wood though, and if it's quite bad, I'd skip the quick fixes and just get the filler out (a decent wood filler with lower water content), sand the surface then fill, sand again and then paint.

In my experience a rushed or shortcut finish on any wooden surface will look like a rushed or shortcut finish. You'll probably end up doing it twice at double the effort.

A second option, and one that seems to be more and more popular in the furniture world, is covering it with either a plain, coloured or patterned melamine sheet. Not for me, personally, but seen a lot of bench tops being covered in it.

Thanks Greig.

I'd already stripped it back to bare wood, sanded it and applied 3 coats of primer undercoat and 2 coats of satin gloss, in the expectation that would give a smooth finish. Was quite surprised to see the grain showing through so prominently. Obviously should have used filler before the primer. Schoolboy error.

I'll look into the melamine idea, but the sill is a complicated shape and I'm not confident of cutting it accurately. Hence the thought of using vinyl wrap.

 

[GreiginFife]

Thanks Greig.

I'd already stripped it back to bare wood, sanded it and applied 3 coats of primer undercoat and 2 coats of satin gloss, in the expectation that would give a smooth finish. Was quite surprised to see the grain showing through so prominently. Obviously should have used filler before the primer. Schoolboy error.

I'll look into the melamine idea, but the sill is a complicated shape and I'm not confident of cutting it accurately. Hence the thought of using vinyl wrap.

Vinyl wrap is a pain to get it to adhere to and stay stuck in my experience.

If you are able to mask off the window and any other exposed areas and use a high build automotive primer, that should fill any smaller pits and troughs that the grain is showing. With ply it's not really grain you're seeing, it's the laminate splitting apart leaving gaps.

 

[cliveb]

Vinyl wrap is a pain to get it to adhere to and stay stuck in my experience.

If you are able to mask off the window and any other exposed areas and use a high build automotive primer, that should fill any smaller pits and troughs that the grain is showing. With ply it's not really grain you're seeing, it's the laminate splitting apart leaving gaps.

Thanks for the info about vinyl wrap.

Interesting comment about the laminate splitting. On closer inspection I can see the "grain" is quite variable. But none of the splits are long, maybe 1cm max. That's why I mistook it for grain.

Looks like will just have to use filler and repaint.

 

[GreiginFife]

Thanks for the info about vinyl wrap.

Interesting comment about the laminate splitting. On closer inspection I can see the "grain" is quite variable. But none of the splits are long, maybe 1cm max. That's why I mistook it for grain.

Looks like will just have to use filler and repaint.

If you are sanding it again, be careful not to blow through the surface laminate of the ply.

I've found out a few times that it's best to spend time doing it correctly than trying to do it quick. I ruined a walnut desk top by rushing a finish a couple of years back, ended up taking me twice as long as cost me a packet.

 

[Doon frae Troon]

Zinsser B.I.N. paint primer and top coat might do the job if the grain is not too severe.
Follow instructions carefully, apply with a roller.
Very expensive but also very good.
It's what the Pros use.

Amazon.co.uk

 

[GreiginFife]

Binder paint under and top coat might do the job if the grain is not too severe.
Very expensive but also very good.
It's what the Pros use.

How would binder solve the problem? It will just flow in to the cracks like any other paint.
Binder is just for pigment.

Personally don’t know any wood finishers that use any form of binder to seal or fill ply.

 

[Doon frae Troon]

We re painted all our 40 year old woodwork from frames and skirtings of dark mahogany to white.
Following advice from my friend, who works at re-furbishing banks, we used B.I.N.
We filled and smoothed all scars and dents then followed the paint instructions for a really brilliant job.
Over ten years on from then it still looks good.
Although the paint was expensive it saved us a small fortune as we were going to replace all the woodwork and doors

BTW you can buy smaller tins than in original picture.

 

[GreiginFife]

We re painted all our 40 year old woodwork from frames and skirtings of dark mahogany to white.
Following advice from my friend, who works at re-furbishing banks, we used B.I.N.
We filled and smoothed all scars and dents then followed the paint instructions for a really brilliant job.
Over ten years on from then it still looks good.
Although the paint was expensive it saved us a small fortune as we were going to replace all the woodwork and doors

BTW you can buy smaller tins than in original picture.

Ok, so Zinser BIN isn't a binder. It's a stain blocker/shellac paint. Using it on something with tight grain like mahogany (or meranti) is very different to using it on plywood.

It's also not a filler, as you even note you had to do the filling.

BIN isn't needed if the are is dry and doesn't suffer mold. A decent water based undercoat and a finish coat of acrylic gloss will do the job just as well.