Veneered MDF - A/B side?

[gidon]

Hi
I bought some 19mm A/B oak veneered MDF from Edens. How does one tell which side is the better side? (I'm sure this has been discussed but can't find it in the archives ) On each sheet one side has what looks like an 1/8 mm laminate under the veneer (not sure if this helps). The grain is different on each side - neither side of the boards looks that bad. Some the repetition is more obvious, but some the grain looks very plain?
Sorry not very well described but hopefully someone can help [-o<.
I don't normally handle full 8x4 sheets - it's a nightmare - they're flippin' heavy!
Cheers
Gidon

 

[tim]

Its worth asking them. With oak boards it is often that one side will be crown cut and the other QS rather than one being better than the other. With maple etc it is likely that the B side is more noticeablly marked or discoloured. Often I have found that both sides are good.

Cheers

Tim

 

[gidon]

Thanks Tim - I will check with them. I've just looked at the receipt - it is referred to as crown cut (guess this refers to the A side?) - but I don't know what the other side is meant to be.
Cheers
Gidon

 

[JFC]

One side as said above is crown cut and the other side will be a balancing veneer ( the one with more repartition in the grain ) Both sides are usable its just up to you to choose what side you want showing .

 

[orangetlh]

you can normally tell by the width of each length of veneer. The face tends to have a lot wider strips of veneer

 

[Scrit]

Gidon

If your board is edge printed with a description (and most are), e.g. "18MM CROWN OAK VEN. A/B", then the face side will be the side visible when the sheet is laid flat on the sawbench and the lettering is right way up (i.e the side nearest the top of the lettering). However, the width of the strips is not always a good indicator of the crown face. Oak MDF is frequently crown one side and quarter sawn on the other and the trade is trying to achieve a uniform repeatable finish - not a distinctive one - so the crown cut veneer is the one generally used as the show face. I agree, though, that if the B side is good enough then that is just as good in certain circumstances. Watch-out for defects such as patch repairs, knocked-out "eyes", defective glue stitching, etc. in QS stuff. Also be aware that when finishing a QS board if the veneer strips are too narrow you can end-up with a distracting, stripey-looking panel, especially if staining to bring-out the ray fleck effect. Withoout seein a board I'd advised you to cut and finish a piece before making your piece of furniture QS side showing (you might be surprised). Some board makers do supply quarter sawn A-grade veneered MDF, but generally only in contract quantities (so not normally available through timber or board merchants) as consistency is apparently difficult to achieve in a batch on batch basis.

Scrit

 

[gidon]

Great - thanks for all the pointers. Scrit, unfortunately the edge doesn't appear to be edge printed - shame because it would have been nice to be sure. I don't quite understand this QS thing - surely quarter sawn would be considered better than crown cut? So why would the boards be specified as crown cut and this be the supposed better side? Hold on - just read your reply again - are you saying it's because it'll be QS - but low grade QS? Is there a good website does anyone know describing all the terminology?
Many thanks,
Gidon

 

[tim]

Not necessarily lower quality but because of the figuring.

The word quality is better exchanged for fitness for purpose ie wild grain patterns are difficult to match evenly across large areas, which is what the largest users of sheet materials will want to do.

Re definitions, I posted it some time ago - I'll see if I can find it.

Here it is although applies to birch ply.

Birch plywood quality is determined according to its face veneer grade. Each side is graded therefore you can have any combination of grades.

B - for high quality, painting, staining and lacquering. Some selection may be required. Mainly white veneers with no patches. Minimal light discolouration permitted.

S - For good quality, painting, staining and lacquering. Some selection may be required. Plug free. More discolouration permitted.

BB - Suitable for interior paint finish, overlays, films and veneering. Knots or holes over 6mm are replaced with oval or butterfly patches - up to 20 per sheet. Dark and light sound knots allowed.

CP - Solid repaired wood patches up to 40 allowed, but generally no more than BB grade. Heavy staining allowed.

WG - For use where face appearance is not important. Sound knots up to 65mm allowed. Heavy staining, rough patches and glue percolation allowed. Can also be fall down grade from higher grades.

C - for use where face appearance is not important. Usually unsanded with splits and small open defects.


Cheers

Tim

 

[Scrit]

Hi Tim

Pretty much what I'd say - "fitness for purpose", although I think you'll only ever find grades A and B in veneer. After B they tend to use a different species for backing (e.g. sapele)

Gidon

...unfortunately the edge doesn't appear to be edge printed - shame ...

In that case it is probable that the A side is the crown cut for the reasons I stated - better quality (less repairs), wider leaves, more consistent, etc.

...surely quarter sawn would be considered better than crown cut? ...

Actually, no. QS veneers are generally narrower and require more repair work to defects (all veneers require some repair work in fact) and the thing about making furniture in sets or batches is that you want consistency and repeatability over "flashyness" any day. The joints in QS veneering tend to stand out and detract from the overall impression in many cases and the furniture trade requires a much less "flashy" finish - for example a 10 ft long piece of Hulsta wall furniture would be simply overpowering if done in QS and you'd really struggle to find matching off the shelf solid wood lippings. In any case oak is no more than a colour to many customers! If you are happy with the QS appearance then fine, use it as your face side, but test finish a piece first to check for consistency.

Scrit

 

[gidon]

Tim - thanks - think that was the post I was thinking of.

Scrit - yep this is A/B. Thanks for the explanation on the QS - think I've got it now. This is a for a built in (very basic) desk for the inlaws - and the QS sides do look to repetitive over such a large area.

In any case oak is no more than a colour to many customers!

And to some it's only a binary colour - ie dark or light!

Many thanks,

Gidon