Plywood has gone furry, fibrous

[Monty_jon]

I left some plywood outside and it's gone very fibrous on the surface, is this normal?

The plywood is quite old as it was up my father's loft for years. (I think it was from originally some large packing containers)

I’m not worried about the piece I’ve left outside, but I’ve made a few workbenches out of the rest

Is there something wrong with it or has it got something on it?

 

[Deleted member 174758]

What"s wrong with it is that you left it outside where it has absorbed water and the grain has swelled. Your description of it as "fibrous" inclines me to think it may be something like Gaboon plywood (often mid to dark reddy-brown), which is fibrous and splintery, especially when cut across the grain. In the past it was often used for packing cases and the like in thicknesses from 4mm up to about 13mm because it was relatively cheap. I don't recall seeing it in thicker sheets
It isn't always particularly pleasant stuff to work with (due to the splinters), but it is pretty stable, although there is no guarantee that the glues used will be waterproof or damp proof

 

[Monty_jon]

What"s wrong with it is that you left it outside where it has absorbed water and the grain has swelled. Your description of it as "fibrous" inclines me to think it may be something like Gaboon plywood (often mid to dark reddy-brown), which is fibrous and splintery, especially when cut across the grain. In the past it was often used for packing cases and the like in thicknesses from 4mm up to about 13mm because it was relatively cheap. I don't recall seeing it in thicker sheets

thank you, this is 6mm thick

It was quite splintery when I cut it, but I'm no expert when it comes to woodworking!

 

[Monty_jon]

I've seen a few pictures of decking that's gone fuzzy, is this the same thing?

 

[opps]

I have seen decking do that when an aggressive pressure washer was used to clean it- That said, I was the person that used the aggressive pressure washer...

 

[Deleted member 174758]

Soak any timber (or leave it outside for long enough the British climate) and you'll raise the grain

 

[foxhole]

Packing crates use very low grade ply .

 

[Monty_jon]

Agreed, I’ve got a tin of old varnish so I’ll seal the benchtops with that