Question about Storing MR-MDF?

[lemonjeff]

Two questions really,

My workshop can be damp, up 85% humidity for very short periods but generally around 70% humidity or lower during dry spells, could I store MR MDF without it soaking up moisture under these conditions?

Can MR MDF sheets be stored upright ok for a few months? If so is there a better way than just leaning them against the wall?


Jeff.

 

[Scrit]

Sheet materials are possibly better stored horizontally although they should never be stored in direct contact with a concrete or similar floor (as they will potentially take-up moisture) and ideally they should be stored either on a pallet or cross bearers at 18in (or less) centres to avoid the material taking on sags. If on the other hand you choose to store upright it should be at no more than about 20 degrees off the vertical and preferably sitting on the long edge, once again to reduce the tendency to sag. Once again the timber will need to be raised off the floor and adequately supported on a cradle such as this:

to ensure that a permanent sag doesn't occur under a combination of the material's own weight and the possible absorbtion of moisture (sorry about the poor sketch, but it was a 2 minute job....). If you just lean them against the wall with no support they will take on a permanent sag.

In either case you should try to ensure that the building has good through-flow ventilation to ensure that any moisture condensing on the surfaces overnight can be allowed to evaporate in the morning before black mould has a chance to form.

Scrit

 

[Anonymous]

For me the answer is to buy only what you need, when you need it. Then you'll never need to store full sheets for more than a week or so. Offcuts can be stored on simple racking for future projects.

Savings made on bulk purchases can soon be lost by deterioration in storage - particularly if your workshop is as damp as yours.

You'll have more room to work, too.

 

[lemonjeff]

Thanks for the info Scrit, the sketch however quick more than adequetly explains whats needed. I don't have the room to store flat so it would have to be something like you suggested.

Hilsty you've hit the nail on the head, I'm trying to decided whats going to be more cost effective, the nearest suppliers are some 15-20 miles away so popping out for the odd sheet or having it delivered is going to add up. On the other hand as you pointed out I could end up with swollen sheets.

Will MR-MDF withstand the amount of moisture I have in the workshop?

Jeff.

 

[greybeard]

My three-happorth for what it's worth; mostly on the topic of bendy MDF, cos I asked a very similar question of a friend who consumes sheets of the stuff, mostly the 12mm and 19mm or thereabouts, in a kitchen joinery business.

He assured me that the 'd**n stuff' (I have edited a few other words out, this is a topic very close to his heart, and I do believe he was getting just a bit emotional at the time!) will bend almost visibly if it isn't stored flat, and even then it needs to be properly/well supported.
He had really horrible tales of it actually bowing on the job when precut lengths had been propped up vertically 'out of the way' for just a few hours. I've no means of knowing whether that was just a wind-up!, but it worked to put the wind up me for sure!

Of course he exaggerated (?I think?!), but he was at pains to confirm that it really does bend/bow very quickly, and that it is almost impossible, and of course usually impractical, to try and restore it to a flat state.

I also asked about damp (my 'store' is not too dry!), and as others have advised he reckoned that it's not actually a sponge, but that it probably belongs biologically in the vicinity of the sponge family.

 

[Scrit]

He had really horrible tales of it actually bowing on the job when precut lengths had been propped up vertically 'out of the way' for just a few hours. I've no means of knowing whether that was just a wind-up!, but it worked to put the wind up me for sure!

He's right! On a damp day the stuff can bow amazingly quickly, although the edge storage rack I've sketched does work providing there's an angle of around 15 to 20 degrees and the sheets are tightly stacked. For that matter vertical storage racking works but you either neeed to keep the racks full all the time or employ wedges to hold everything dead verical, hence my reason for not recommending.

Scrit