Thread: Help with building custom shelfs.

Cost wise, I think you'd be better off buying cabinets from Ikea, unless you are able to get things such as the acrylic sheet for free (for a plastic, it's surprisingly expensive). Fully enclosed, glass fronted cabinets also keep the dust off better than shelves.

http://www.ikea.com/au/en/catalog/products/S39020506/

(At least, that's what Adam from Mythbusters did for his movie prop collection)

Thanks for that but it's no good due to the size of some of my display pieces there would not be enough room in those.

Hi and welcome

2.7 METRES is a serious span even for an empty shelf. Let alone one with something displayed on it.

If an 800mm wide Ikea book shelf unit is too narrow, or shallow, I strongly suggest you get your display shelves custom built.

without knowing what you are planning to display, my first suggestion is a stainless steel frame

I saw the 2.7span and questioned it myself. So I plugged in a few details into the sagulator. http://www.woodbin.com/calcs/sagulator.htm and to my surprise it passes with 30mm thick hardwood shelves, MDF fails miserably.

I would use hardwood shelving and support all 3 edges using cleats. You can put a stopped rebate on the underside of the shelves to conceal the cleat, it can only be seen from underneath. Or u can use angle iron and run a groove in the edges of shelves to accept the iron "tongue" for completely concealed fixing except for some screws stopping the shelf from shifting forwards.

Hi Kuffy

given the shelves will be 700mm deep, I plugged in 20kg / foot as the load -- which returns 40mm for thickness

whether it's 30 or 40mm hardwood, each shelf would be a serious piece of wood -- weight in teh order of 45kg per shelf

Oh, I thought the calculator takes the weight of the shelf material into account automatically. So I just chose white oak at 2700mm span, 700mm deep at 30mm thick with a total load of 30kg and it gives less than a mm in deflection.

But if It needs the shelf weight added, I dunno how heavy it is, but at a guess I would say about 60-80kg. So about 10kg per foot for shelf plus 4kg/foot for stuff on the shelf gives about 3mm deflection which is pretty crappy and it only gets worse as more stuff gets put on the shelves.

The design probably needs atleast one support in center of span.

Thanks for the replies guys...Not sure if it's a silly question but would I maybe be better off building just big rectangular boxes and sitting them on top of each other?

"boxes on top of each other" is another way of describing shelves with intermediate supports

if the shelves need to be 700 deep, the implication is that the items are rather heavy which in turn means thick shelves.

it would help some if we had an idea of what the "movie memorabilia" is

Originally Posted by Kuffy

Oh, I thought the calculator takes the weight of the shelf material into account automatically. So I just chose white oak at 2700mm span, 700mm deep at 30mm thick with a total load of 30kg and it gives less than a mm in deflection.

But if It needs the shelf weight added, I dunno how heavy it is, but at a guess I would say about 60-80kg. So about 10kg per foot for shelf plus 4kg/foot for stuff on the shelf gives about 3mm deflection which is pretty crappy and it only gets worse as more stuff gets put on the shelves.

The design probably needs at least one support in center of span.

I think sagulator takes the shelf weight into account -- it will be pretty much a constant on a square foot basis anyway -- I was more intending to advise the OP that the shelves themselves would have a significant weight.


but back to the shelves themselves -- I chose Meranti and simple supports
Because 700mm deep is around 3 times the depth of an Ikea shelf I allowed 10kg / foot for the load and checked for a 150kg total load. Sagulator suggests minimum 40mm shelf thickness

Sounds like the shelves would be better off as torsion boxes.