4mm pine to MDF

[Destructive Dave]

A decent timber merchant will plane that to size but will charge for the service, otherwise design your door around standard sizes.

How do you mean plane it to size? I'm no joiner I understand that but it doesn't stop me from trying and enjoying which is the main thing. I wanted a big rustic looking wardrobe from the floor to ceiling and I'm 80% done and happy with my progress. Next time I will account for standard sizing like you say it's just a school boy error, you live and learn.

 

[TheTiddles]

Yeah, you should be able to buy that, have you got any pictures?

a

 

[Trevanion]

Bear in mind Dave said 76x158cm which means 760 x 1580mm doors, I would notbe doing that in a single panel of pine because it would warp on itself and you'd end up with U shaped doors, it would have to be a framed door with a floating panel.

 

[Destructive Dave]

I've remeasured to 72cm I'm going to have 18mm ply cut to measure, process my 4mm ply beams and wood glue them to the ply on the untreated side. Making it 22mm doors. Shirley it wouldn't suffer warping would it??

 

[TheTiddles]

Bear in mind Dave said 76x158cm which means 760 x 1580mm doors, I would notbe doing that in a single panel of pine because it would warp on itself and you'd end up with U shaped doors, it would have to be a framed door with a floating panel.

Oops! Not my fault he’s using weird unit!

 

[spb]

I've remeasured to 72cm I'm going to have 18mm ply cut to measure, process my 4mm ply beams and wood glue them to the ply on the untreated side. Making it 22mm doors. Shirley it wouldn't suffer warping would it??

Pine will expand and contract with the seasons; plywood won't. If your pine covers the whole of one face and expands, then the plywood sheet will have no option but to warp in order to make room for the pine. The only way to prevent this is to make your wood veneer thin enough that it can be held in place when the moisture content changes, and to balance it with the same veneer on the other side. As custard said up above, the limit for this is typically 1mm thick - not really enough to be burning.

If you need something in that size, with a thick face of solid pine, I'd be looking at something more like a planked or boarded door with braces behind to keep it flat. It'll look more ... rustic than a single smooth slab, but it'll last a lot longer. MikeG did one a few months back that you can look at.

 

[Destructive Dave]

How about routering out brace wells In the ply? Also what about treating the pine beams before bonding to the ply? Would rule out wood glue probably but maybe no nails or epoxy?

 

[Destructive Dave]

Also the intention although not what I'm using it for of shou sugi ban is to preserve the wood wouldn't that prevent moisture?

 

[TheTiddles]

I think you will have a lot of issues in this approach, I’d really try it on a test piece. But the whole thing sounds interesting, please post some pictures

Aidan

 

[AJB Temple]

shou sugi ban does not "prevent moisture" it just resists rotting.

 

[profchris]

Also the intention although not what I'm using it for of shou sugi ban is to preserve the wood wouldn't that prevent moisture?

If you char it the whole way through, yes.

But wood constantly absorbs or loses moisture to the atmosphere, as humidity changes. Across a panel that size you could see 10 mm or more of movement across the grain, and that's enough to bend your ply over time.

Building to account for humidity changes is an important thing to learn.

 

[AJB Temple]

If you char it the whole way through, yes.

So that would be charcoal then

 

[Destructive Dave]

What about treating the wood first wouldn't this stop the moisture? It's sealing the wood I understand that moisture is a threat as you all show concerns with it and so will I. I stated about treating the wood first and using no nails or epoxy but nobody has advised if it's a good approach. Who crashed the site today?

 

[TheTiddles]

You really can’t stop moisture, short of a complete seal with resin and fibreglass. That’s part of the fun in woodwork, the material moves and keeps moving, a good piece accommodates this and still looks good

if you put thick pine on one side and thin on the other, they will both expand but the thicker will exert more force. Timber treatments just prolong the life of wet wood, it’s still wet

Aidan

 

[Destructive Dave]

So completely sealing the wood in varnish wouldn't stop moisture, got ya. We're talking pine on ply now as per my intention, it's either seal the wood first and bond with poxy or no nails to ply or bond untreated to ply with wood glue. Decisions decisions

 

[Destructive Dave]

So that would be charcoal then

Groovy

 

[TheTiddles]

Completely sealing in varnish may be possible, but you’ll keep in the moisture that’s there now and as a glue surface it’s terrible

aidan

 

[Destructive Dave]

So toast both side seal with varnish attach with poxy or no nails. throw a bucket of water over it every year? Sounds like a plan

 

[AJB Temple]

This is usually the point where someone suggests using rare earth magnets.

 

[Trevanion]

Now, heres the thing with rare earth magnets...