Max load on MDF?

[maxima]

I am going to build a custom cupboard which will have shelves 65cm D x 62cm W.

I am going to use 18mm MDF and attach shelves to the sides by screws.

Can anyone please tell me - is it good idea to screw MDF parts together or shall I look into some kind of support for shelves from beneath (like angle brackets)? If screws are OK how many I need on each side and what size?

And the most important - how much of uniform load the shelf can hold safely?

 

[foxhole]

You can screw thru the sides into shelf but you need to pilot hole each fixing and stay at least 80mm from any edges to avoid splitting.Glue as well for sturdier shelves. Or you can use small brackets which support from below and remove the risk of splitting which mdf is prone too if not treated correctly.
Should take a fairly heavy load, certainly OK for books etc, what do you want to load it with?
If screwing use 4 screws per side about 50-60mm with brackets 3 per side will suffice. You can increase the strength by adding a 50mm strip of mdf [or 2"x1"]glued/screwed to front edge but with reduce spacing between shelving.This also reduces bowing.

 

[maxima]

thank you.

all kind of load. the house has no storage but very big kitchen so I took the corner and building a storage effectively. 3.2m high (2 cupboards on on top of another). the books and papers will be the heaviest I imagine. Can it hold 90Kg in extreme case?

by adding a strip you mean to screw/glue the strip to the sides and then screw the self to the strip to make 3d side of support? can it be done on the back?

 

[foxhole]

No the strip is for below the front edge to strengthen it and prevent it bowing.
The rear can be supported off a fixed rear panel.

 

[maxima]

clear now. thank you very much