Mdf?

[Dana G.]

I plan to build a platform bed for my daughter. The structure will incorporate both shelving and storage. I will most likely paint it white. So my question is, would MDF be a suitable choice? And if not, what do you suggest?

Thanks

[FINER9998]

MDF is okay for non structural elements. I have used it to make moldings for a remodeled kitchen as I knew I was not staining the trim. Be careful using screws; its easy to split mdf if the pilot hole isn't matched to the screw pretty closely. I've seen mdf used in cabinetry for things like door inlays for recessed or raised panel doors, but surrounded with real wood stiles and rails. And three more things: it's heavy, makes a lot of dust and may be harder on saw blades than a softwood like pine.

[CheekyMonkeyWrench]

i made a basic shelving system with mdf. the corners chip like crazy, the shelves sag, and the screws are releasing. i have yet to rationalize what this product is for.

[CWSmith]

I've made only one project with MDF and frankly, I really don't like it at all. I know some of the posts I've read have lead me to believe that I'm using the wrong fastening techniques, etc., but overall, I've found MDF to be pretty poor for anything but workbench tops and perhaps simple projects where strength and/or ridgidity isn't of any concern.

My project entailed a rather simple wall unit with a couple of storage areas in the bottom with hinged doors. The upper portion would be open shelves for some of my referance books. I started off thinking MDF for the whole project, but quickly discovered that the doors wouldn't hold hinges without splitting, so I made those out of pine. Also, I knew the shelves couldn't be too wide, so I made them only 20 inches and provided a support across the back. They still sagged, not drastically, but enough to be noticeable. The sides also buldged outward (like a pear), even though I used screws to tied the top, bottom, and middle together with fixed shelves at those locations, as well as wall mounted bracing in the back. Overall, a big disappointment, and I've vowed never to use the stuff again.

MDF isn't much more than dust that is mixed with some kind of resin and then pressed together. As such, it has great "compression" strength, but very little tensile or shear strength. It also bends or sags over time. Screws directly into the ends or sides will cause it to spit and if threaded directly into the surface, they can pull out under stress. So, you need to eather bolt the stuff together using inserts to hold the screw or bolt threads or else use anchors that will sandwich the MDF between the anchor and the head of the fastener. Also, because MDF is mostly glue, you need to seal everything with paint or sealer to minimize out-gassing.

For what you describe (painted), I'd go with pine or a combination of pine and plywood. It will be lighter in weight and much easier to work with. Poplar would also be a good choice, but it is somewhat more expensive.

I hope this helps,

CWS

[Pipestone Kid]

i made a basic shelving system with mdf. the corners chip like crazy, the shelves sag, and the screws are releasing. i have yet to rationalize what this product is for.

Cheeky-- I have found it makes very good firewood. :D :D

[CWSmith]

Pipestone,

Actually it doesn't make good firewood at all. The chemical makeup of the glue often contains formaldahyde which is a carcinogin. There may also be other chemicals that are not healthy.

I have asked my local HD for a datasheet on this stuff, but they don't have a clue. They are supposed to keep these handy for customers (I believe it's a legal requirement), but they don't.

CWS

[BadgerDave]

Here's a copy of a MDF MSDS, http://www.norbord.com/MSDS_MDF_Eng.pdf

[Someguy]

Don't be knocking MDF! It is great stuff for making dispossible jigs and fixtures for the shop. ;) :D

[wbrooks]

It is also a necessary evil for building speaker cabinets. I use rabbets for all edge joints and dadoes for all interior partitions. All joints are glued and screwed with course thread screws, course thread drywall screws also work. I hate the stuff but there is nothing better for speakers. I always wear a respirator (not just a dust mask) and use a dust collector

[Pipestone Kid]

CWS, You are so right. What I was saying (tongue- in- cheek) was that was the only good thing I could think of for a use and you reminded me that it isn't even good for that. :D

[Bob D.]

I think poplar would be a better choice than pine, and probably cheaper than a decent grade pine too.

Poplar

General Description
The sapwood is creamy white and may be streaked, with the heartwood varying from pale yellowish brown to olive green. The green color in the heartwood will tend to darken on exposure to light and turn brown. The wood has a medium to fine texture and is straight-grained; has a comparatively uniform texture.

Working Properties
A versatile wood that is easy to machine, plane, turn, glue and bore. It dries easily with minimal movement in performance and has little tendency to split when nailed. It takes and holds paint, enamel and stain exceptionally well.

Physical Properties
A medium density wood with low bending, shock resistance, stiffness and compression values, with a medium steam-bending classification. Excellent strength and stability.

[Hector B]

Wow Bob D. Where do you find info on wood like that? Is there a website you could recommend? Or a book?

I think poplar would be a better choice than pine, and probably cheaper than a decent grade pine too.

Poplar

General Description
The sapwood is creamy white and may be streaked, with the heartwood varying from pale yellowish brown to olive green. The green color in the heartwood will tend to darken on exposure to light and turn brown. The wood has a medium to fine texture and is straight-grained; has a comparatively uniform texture.

Working Properties
A versatile wood that is easy to machine, plane, turn, glue and bore. It dries easily with minimal movement in performance and has little tendency to split when nailed. It takes and holds paint, enamel and stain exceptionally well.

Physical Properties
A medium density wood with low bending, shock resistance, stiffness and compression values, with a medium steam-bending classification. Excellent strength and stability.

[MDF monster]

I don't know if it's your source, BD, but I found this by Googling the above paragraphs:

The Center for Wood Anatomy Research at http://www2.fpl.fs.fed.us/

Tax dollars at work!

ps - I guess I gotta change my login name, based on some of the posts in this thread....

[Dana G.]

Thanks for the input guys!
Dana

[Dana G.]

Same issues with Melamine?

[Bob D.]

"Wow Bob D. Where do you find info on wood like that?"

Yes, there are many sites with enough material to keep you so busy you won't even have time to use your tools :-)

You can try here for a fairly long list of woodworking related sites:
http://home.comcast.net/~sparc/woodworking/woodworking_bookmarks.htm

The one I looked at was this: Hardwood Information Center (http://www.hardwood.org/)

[Hector B]

I thank you greatly Bob D. Two excellent links.
M2C1

[Orange Apron]

Same issues with Melamine?

Melamine is just a particle board (weaker than MDF) with a colored coating on it. Melamine is the second from lowest of the low, with regular part. board being the lowest)

[AnthonyD]

I would use plywood and solid pine , . I use MDF for stiles and rails on small rasied panel doors that are painted. Like anything else MDF has its purpose , in your case consider your options. Good luck

[RevEd]

I use MDf for all sorts of things however you have to know it's limits. For instance it won't work as an unsupported 4 foot shelf. It will split if the right screw/nails are not used. It will water damage and it is heavy.

I use it where I would use wood or ply and it will be painted. I have also found that if you finish it in tung oil and a coat of poly it looks alot like leather.

While dusty it is fairly easy to cut, shapes good with a router and once painted it pretty stable.

I usually use it for stacking cubes that as so popular now, bed platforms, anything I need a really flat surface on, jigs/fixtures, templates, architectural mouldings, decorative pieces and router cut mock raised panel door.

My wife had me contruct 8 columns that were fluted to go between some mirrors. They had to be about 3 inches proud of the mirror and have top and bottom finals that were intricately routed. I use MDF and was able to cut rout and finish the columns so the finished product looked like marble. Had I used anything else the cost would have been out of sight.

Like everything else you just have to know what your doing and the limitations of the product.