Mdf Shelves, need some advice please

[leevis]

Hi
I am in the process of making 5 mdf shelve which are U shaped and have 4 rouded edges on the 4 internal corners.
I have done this with a hole saw and a jigsaw and they kinda look ok (only going to be in a cupboard anyway) but i was wondering how to finish these off.
My cutting of the widths wasnt the greatest so they are a little short but i will be attaching some quadrant to the external sides of these to hide my mistakes plus i think that they will look a bit better this way.
My question though is to do with the front edge.
What would be the best way to finish these, the mdf is 12mm, is there a plastic strip this size that you can buy and would it be worth it? The reason i ask is would be pliant enough to go around the rounded edges easily?
Or would be easier just to prime, sand, prime again and then gloss?
Help
Lee

 

[big-all]

how wide is the span on the front edge

 

[leevis]

From memory its around 81 inches, 12 mm high

 

[big-all]

dependent on load you will need 1 or 2 intermediate supports and or a supported front edge with something like 18x44[2x1" par] timber rebated 12x12mm

how deep are the shelves and likely load

 

[leevis]

Its only for shoes, will be supported with batons at the back and sides so should be ok but i might go for another one, the question was more about the finish of the front of the mdf

 

[foxhole]

I would have used 18mm , easier to fix , less support required and generally cheaper than 12mm and then bull-nose the front.

 

[big-all]

it will sag if unsupported as i said above 2x1 with a rebate you may get away with it thick edge to the face i would still want 1 support along the span this can be a dividing panel under the shelve

 

[leevis]

Good idea, a vertical divider, nice one.
On painting the mdf on the edge (nasty) side, whats the general opinion?
I have read multiple layers of emulsion (about 3) each one sanded down afterwards but i have also read one layer of pva sanded down afterwards.
Whats the best way?
Lee

 

[foxhole]

I use either mdf primer or emulsion [cheaper if you have some] which seals the mdf ready for whatever you want on top.