different grades MDF?

[NCPete]

ok, I know that this isn't exactly wood, and many of us may prefer not to do anything with this material, but has anyone else noticed different 'grades' of MDF when buying from different vendors?

Lowes - seems to be very light in color, and really fine 'grained' and creates a very fine dust. mills very cleanly

Home Depot - seems to be much darker, not so finely 'grained', and the dust seems to clump more, and milled edges aren't as smooth as expected.

any others?

sure wish my Lowe's in Fayetteville (we have TWO) would stock some of that real 3/4 ply!

 

[michaelgarner]

ok, I know that this isn't exactly wood, and many of us may prefer not to do anything with this material, but has anyone else noticed different 'grades' of MDF when buying from different vendors?

Lowes - seems to be very light in color, and really fine 'grained' and creates a very fine dust. mills very cleanly

Home Depot - seems to be much darker, not so finely 'grained', and the dust seems to clump more, and milled edges aren't as smooth as expected.

any others?

sure wish my Lowe's in Fayetteville (we have TWO) would stock some of that real 3/4 ply!

Ya some nice 5 or 7 ply birch would be great. Guess we will have to take Lowe's by force and make them order what we want. LOL

 

[DaveO]

I don't think that there is grades of MDF like there are in plywood. But I am sure that there is differences in quality between different manufactors, and so there will be slight differences in product bought at different suppliers.
Dave

 

[chris99z71]

I wonder whether the difference is so much from supplier to supplier or the storage conditons of the MDF. I've experienced the same differences that you speak of and my thought that it is due to the moisture content in the "wood". More moisture = darker color, rougher edges and more clumping of the resulting dust. Less moisture = lighter color, better edges and finer dust.
I'm not saying that this is definately the case, the data just fits the theory.
Lots of questions:
Does it sit outside before they bring it in?
Is it transported in an open or closed truck?
How tightly is it covered in transit?

 

[DaveO]

Chris that is a very good point. Do you think that the moisture content of the original wood dust that the MDF is made out may have a effect also?

Dave

 

[Travis Porter]

I have seen it as well. I think I remember a FWW article about the different types and grades a while back.

As for 7 ply plywood, IIRC, I have bought it at what used to be Carolina Builders. Price was as good or better than the BORG.

 

[Ray Martin]

I have seen it as well. I think I remember a FWW article about the different types and grades a while back.

As for 7 ply plywood, IIRC, I have bought it at what used to be Carolina Builders. Price was as good or better than the BORG.

Didn't that FWW article talk about the three weights of fiberboard? Light, medium and heavy? I seem to recall the article noting the overall weight of a full sheet, and me thinking I would never work with the really heavy stuff due to the weight.

Ray

 

[Travis Porter]

It did cover that. I remember thinking as well I never want the heavy stuff either.

 

[DaveO]

According to the FWW website that article should be in Issue #104, if anyone has it.
Dave

 

[McRabbet]

I have Issue 104 of FWW (Jan/Feb 1994) and after reading the article, I would conclude that the differences in quality are probably due to the manufacturer, versus handling. I have seen cases at Lowe's and the BORG where MDF has gotten wet and it is very obvious because it swells and tends to separate in layers. The article cites 9 manufacturers back then and the heavy usage of MDF by specialty furniture and display shops for its superior machinability (it can be kerf-bent, holds good moulding edges and glues well). The dust it creates is a problem and it does contain urea-formaldehyde (use good sealers). It is cheaper than 7-layer plywood but about 40% more than particle board. I use it for jigs and templates because of the above properties and the fact that it is dead flat (again buyer beware of poorly stored material at the home centers.

Rob

 

[NCPete]

Thanks Rob!

 

[chris99z71]

Good info, Rob! I guess that my guess was a little off.
Sorry Dave, I guess I forgot about this thread and didn't answer your question...I think that Rob did though.