faux buiult up moldings--design question

[tom coleman]

I am looking at a plan in Handyman magazine for a 3 unit shelving system. Two side units about 68 tall and 30 wide and a center unit that is 80 tall x 40 wide. The center unit is deeper than side units. The author suggets using 2 pieces of 3/4 stock for a layered top and for a layered base. Size these pieces to give impression of built up moldings. Pretty clever and not too difficult to execute. My question re what profile to cut. My family room where this unit would be installed has 5 inch crown cove molding on the ceiling. Should I cut cove profiles on edges of the 2 base pieces and 2 top pieces to sort of match the ceiling or doesn't it matter. The author used bun feet under each unit, I think I prefer rectangular base. I plan on painting the units and may use mdf for tops and bottoms...........I heard mdf is excellent for painting and easy to route edge profiles. Yes/No? Thanks--my first furniture piece beyond simple bookcase.

[Joe Scharle]

From bottom up; ogee to roundover is a safe profile. I built some bookcases a couple of years ago using a similar construction technique, where the bottom is a web frame with furniture wood on the exposed front and poplar on the other three sides, followed by furniture wood for the base top. I like the web frames for cabinetry because if I can get the small, lightweight web frame squared.....then the large cabinet will follow.
And even though MDF mills nicely (no grain) it will quickly dull an edge. Hone your router bits before use. Have fun...

[Prashun Patel]

I wouldn't use MDF for the edges. It holds up well for crown and is a good choice where the walls are wavy. It also copes and rasps very easily, so inside corners are easy. However, for a shelf unit or base, it will take a beating after several years. I would use poplar if you are going to paint.

Can you post a pic of the suggested edge profile? I'm contemplating the same thing for a media console top. I'm thinking bull nose edge with a cove underneath.

Personally, I don't believe the molding needs to match; but the style should. If your crown is angular and Shaker, then I wouldn't put a lot of ogees and curves and fillets on the edges. However, if the crown has some curves and fillets, I find as long as you incorporate a similar element on the edge or under the shelf, it ties in. My 2c.

[Rich Engelhardt]

I heard mdf is excellent for painting and easy to route edge profiles. Yes/No?
Use poplar - MDF is just plain nasty.
Poplar takes paint well also & it doesn't make the nasty dust MDF does.

Routing MDF is like taking a dozen cans of snuff and tossing it all over the place.

[Myk Rian]

Routing MDF is like taking a dozen cans of snuff and tossing it all over the place.
Ain't that the truth. :)