4mm pine to MDF

[Destructive Dave]

I'm looking to bond some strips of pine to MDF as wardrobe doors. Is it advisable? Would bonding to plywood be more suitable? I'm wanting to do Japanese wood burning on the pine as a feature and use the MDF/Ply for structure. Any help for a noob of the realm?

 

[MikeG.]

No problem at all. It's done all the time.

 

[Myfordman]

Ideally use MRMDF and appy the veneer to both sides to avoid warping. Similarly apply finish to both sides

 

[MikeG.]

Ooooh, I wasn't reading it as a veneer. If it is, then Myfordman has the right advice.

 

[Destructive Dave]

Is it necessary to vaneeer both sides if I use 18mm MDF? The pine is 4mm. Would you seal the MDF first and use wood glue? Thanks for replies

 

[TheTiddles]

Is it necessary to vaneeer both sides if I use 18mm MDF? The pine is 4mm. Would you seal the MDF first and use wood glue? Thanks for replies

Yes (and no to the second question) hope you’ve got a vac bag?
Aidan

 

[Trevanion]

Are you burning it before or after bonding?

 

[AJB Temple]

If you are using burnt 4mm pine facing as shou sugi ban I would prep that first - including all finishes - and personally I would use 18mm ply rather than putting pine on the back as well. 4mm pine will burn really easily.

 

[custard]

This gets a bit contentious. Really thick (up to about 3/16"), saw cut veneers we're often laid onto soft wood substrates for antique furniture making, and even today you have engineered wood floors where similar thickness veneers are laid onto ply cores.

BUT, none of that means you'll get away with your plan!

The chap who was John Makepeace's head cabinet maker at Parnham (and the same chap that actually built the Millennium Chair, possibly the most iconic piece of 20th century British furniture) conducted exhaustive trials to determine the optimum thickness for saw cut veneers. There's loads of ifs and buts, however in a nutshell the conclusion was that you go above 1mm at your peril! And of course the backing veneer needs to be similar thickness and from a species with similar density.

 

[Destructive Dave]

Yes I will doing all prep before bonding when you say Ply I hope you mean the cheaper stuff as the price of quality birch etc has put me on to vaneering I was just going to toast the Ply but it's expensive for high grade in my opinion I see a better finish and a lot cheaper this way. No vac bag!

 

[TheTiddles]

I’d try an experiment on a small bit first. I suspect you will end up with a burnt toast look.

To do a large area you’ll need a vac bag or a veneer press, the glue you will use will take some heat and probably steam, I’d be impressed it anything less than epoxy held up.

do you know dyed ash will be black and shiny too? maybe that would be easier

Aidan

 

[custard]

The scorching element brings all sorts of challenges. Firstly all the adhesives that you're likely to use, from epoxy to PVA, are heat sensitive. Then you've got the fact that scorching around an edge is much more aggressive than scorching a flat surface (when I scorch and iron stain furniture, which I do regularly, I give a much more gentle round at every arris to combat this. On your panels you may need to scorch and then trim off the edges.

Another thing is that scorching generally ends up looking a bit patchy. You've either got to stain over the scorching (so the scorching is done for texture and the stain delivers the colour), or you've got to practically incinerate the piece!

Before you spend much money do a trial first, that may persuade you to think again.

 

[AJB Temple]

The scorching element brings all sorts of challenges. Firstly all the adhesives that you're likely to use, from epoxy to PVA, are heat sensitive. Then you've got the fact that scorching around an edge is much more aggressive than scorching a flat surface (when I scorch and iron stain furniture, which I do regularly, I give a much more gentle round at every arris to combat this. On your panels you may need to scorch and then trim off the edges.

Another thing is that scorching generally ends up looking a bit patchy. You've either got to stain over the scorching (so the scorching is done for texture and the stain delivers the colour), or you've got to practically incinerate the piece!

Before you spend much money do a trial first, that may persuade you to think again.

I agree. as I am developing a Japanese style garden, with buildings, I've been experimenting with shou sugi ban. It is a lot more difficult than people think (and you tube videos suggest) to get a good consistent finish. The best ones IMO are very charred. I would not personally use it for an internal finish. I've experimented a bit with oak (I have a surplus of rough sawn oak roof laths) and larch. Tried wire brushing and different depths of burn. Have not fitted any to an actual building yet.

 

[Trevanion]

I've machined a couple thousand meters of douglas fir half-lap for burning recently, my only worry is that is it going to look extraordinarily naff in a couple of years like most of these stupid trends.

I have toyed with the idea of a burnt staircase in my head though, might look interesting.

 

[AJB Temple]

I've machined a couple thousand meters of douglas fir half-lap for burning recently, my only worry is that is it going to look extraordinarily naff in a couple of years like most of these stupid trends.

I have toyed with the idea of a burnt staircase in my head though, might look interesting.

You may well have a point. I have travelled in Japan extensively but I don't recall ever seeing burnt wood cladding. I came across it on You Tube.

 

[TheTiddles]

It’s like river tables, upcycled pallets, tensegrity, skinny jeans and beards, just give it time and the naff-ness will be apparent.

However a well proportioned refectory table will look good for centuries.

Aidan

 

[Destructive Dave]

I have already done testing and staining with exceptional results. You do have to scorch to a depth to get the grain groves that manifest with using flap brush. My only problem is the dye I'm using kindof dyes the charred parts until I lift it with wire wool. Maybe an oil based dye would work better? I've used littlefairs water based because I want a real unique colour showing through the light parts. It's just going to be a lot work to lift the dye but the overall finish with contrasting groves and colour looks awesome call it fad if you like but sure as hell looks better than laminate veneer which I was doing up until I saw the wow factor from my own testing

 

[Woody2Shoes]

Silly question - why not just use solid pine? That would remove a whole set of risks/imponderables and cost (in materials and time quite likely). If I were scorching pine, I'd be particularly wary of setting fire to and/or liberating sap from around knots and/or sap pockets.
Cheers, W2S

 

[Destructive Dave]

Good question, I've not been able to find solid pine in the required size I need for the doors. I've searched everywhere online without luck. 76x 158cm

 

[Myfordman]

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