Thread: Thicknessing Painted Timber

It all has to do with hardness and abrasion. The paint is harder than the HSS used in thicknesers and it will abrade the blades very quickly. It is less aggressive on carbide but will still dull them more quickly. The wood is much less hard.

John

Paints often have "solids" added to them, might be kaolin clays and so forth.

You all still use HSS and carbide in your thicknessers? Why? Ceramic blades have been the norm here for decades.
No. They are not perfect, nothing is. But they do last a long time. Ceramic blades in my kitchen seem about the same.

One of the main ingredients in paint is titanium dioxide, which is the base white pigment, and other metal oxides are often used for coloured paints. They're also all quite abrasive, so when you machine painted timber you're basically machining timber with a thin layer of sandpaper stuck on the top.

What are these ceramic blades you speak of? Never come across them before.
BTW, tungsten carbide technically IS ceramic

Bugger. Wish I had read this post two days ago. I have just thicknessed a whole heap of painted boards with my new spiral head thickie!!!!

Originally Posted by Damienol

Bugger. Wish I had read this post two days ago. I have just thicknessed a whole heap of painted boards with my new spiral head thickie!!!!

Hi Damienol, I thought you were following my post where I am cleaning up all the painted recycled timber I have with my thicknesser/jointer blades BEFORE I put the spiral heads in.

Cheers

Doug

Originally Posted by doug3030

Hi Damienol, I thought you were following my post where I am cleaning up all the painted recycled timber I have with my thicknesser/jointer blades BEFORE I put the spiral heads in.

Cheers

Doug

did not compute

Thanks all.

Originally Posted by Damienol

Bugger. Wish I had read this post two days ago. I have just thicknessed a whole heap of painted boards with my new spiral head thickie!!!!

Well its buggered now.... better give it to me.

Originally Posted by cava

Most of us understand that trying to put painted timber through a thicknesser will dull the blade quickly. This is especially true of oil based paints..

I haven't noticed any difference.
Both oil and water based paints contain similar amounts of TiO₂ and it is this which buggers up the blades.

FWIW TiO2 is about the same hardness as silica, glass or garnet, so think of thicknessing a piece of sand paper while you are doing it.

A side issue might be that oil based paints take longer to dry so they might pickup a bit more grit during drying.

I notice that paint is usually softer after the surface has been cleaned with a high pressure washer. Wonder if this will make the plane blades less buggered with the painted surface is high pressure cleaned immediately before being planed?

Originally Posted by justonething

I notice that paint is usually softer after the surface has been cleaned with a high pressure washer. Wonder if this will make the plane blades less buggered with the painted surface is high pressure cleaned immediately before being planed?

It won't make much difference. The binder or resin is what has become softer but it won't change the hardness of the TiO2 = it will be like thickening wet sandpaper.

I wonder what the best way is to remove the painted skin from timber quickly then?

Removal....heatgun and mechanical stripper. Or; as happens here with house wooden weatherboards; the hot sun quickly destroys all types of house paints.

Ken

I put a partially painted crate through. Is that enough to stuff the inserts?

Now what to do with the other 4 crates!!!