Carpentry and Woodworking - 3/4" oak, mdf vs plywood core

would like to build some cabinets and bookshelves. i see that there are two types of oak veneered products out there. one looks like regular plywood except the outer layes are oak veneer. the other has an mdf core with oak veneer. what are the pros and cons of both? is one stronger than the other? i've used biscuits in the plywood type on other projects; does the mdf accept biscuits?

thanks,

The MDF is a lot heavier. MDF takes glue and biscuits well. It does poorly with other fasteners unless you bolt through the material or are using a fastener to hold a joint until the glue sets. Air driven fasteners tend to telegraph through the piece where the fastener enters the end. Drilling pilot holes and driving square threaded fasteners would be better. MDF has no grain or true structure and fasteners alone do poorly, in general.

To me, the only advantage that MDF has is cost.

Hope this helps.

Having recently built a large cabinet and several book shelves and making several mistakes, here's what I've found.

Be picky about the plywood, then clean it with paint thinner or such before trying to stain it. Mine had shoe prints on it after the stain was applied, and only hours of sanding and re-staining fixed it.

I used 1/4 round to hold up shelves, using short wood screws and glue to fix it all in place. Driving screws into plywood was a bit troublesome, but overall it worked well.

Use real board when possible (i.e. book shelves) when the pieces you need aren't too wide to be practical. Real wood, even cheap pine, is easier to work with, doesn't need trim on the edges, and accepts screws and such much more easily.

I just recieved the October issue of popular woodworking and low and behold there is a chart in there that tells all the info you need to space your shelving to keep it from sagging.

3/4'' material
solid wood max span 36''
vaneer core ply max span 36''
MDF max span 32''

and here is a weight chart to tell you what kind of weight the span can hold for the materials. I am only putting the harder woods in here becouse that is what you stated you wanted to use and the list is long

Hard maple and red oak 36'' span 313lbs
MDF 36'' span 87lbs
MDF with .05'' thick laminate 36'' span 205lbs
MDF with 1/8'' wood edge 36'' span 79lbs
MDF with 3/4'' wood edge 36'' span 90lbs
MDF with 3/4''x1 1/2'' wood edge dropped 36'' span 241lbs