Shelving mistake?

[edl]

Opted for MDF board as shelving material - good cutting characteristics - holds weight well - BUT, one application I had not thought of was screwing various typed of hooks or other under shelve storage solutions that would mount/screw in to the under side of the MDF board

- is MDF up to this kind of application?
- can it hold as much weight on something hanging on a hook as the equivalent thickness (3/4") plywood?

If not, what would be some solutions to using these applications with MDF (for example, drill a hole and let hooks pass through and attach to some sort of spreader on top - as you would for drywall ceiling mounts)?

thanks!
stephen

 

[MXtras]

MDF has more tendency to sag over time. It handles well, looks good and is uniform, but it does not handle weight as well as plywood in my opinion. It may depend on how much humidity it is exposed to (?).

It definately will not hold a thread as well as plywood. They make special threaded screws specifically for MDF but I doubt you will find hooks and other hangy things made specifically for MDF.

I would suggest drilling through and countersinking machine screws through to hang stuff. You might also want to stiffen any unsupported lengths with small pieces of angle or a firing strip along the leading edge of the shelves, for example.

Scott

 

[edl]

I would suggest drilling through and countersinking machine screws through to hang stuff. You might also want to stiffen any unsupported lengths with small pieces of angle or a firing strip along the leading edge of the shelves, for example.

Scott, many thanks - sorry for being such a novice - can you elaborate on the "countersinking" - I don't quite follow; also, what is a "firing strip"?

Separately, if I go to plywood, is there an easy way to bullnose (round) the leading edges?

thanks,
stephen

 

[the intimidator]

I would simply run a strip of 1/2x3 inch pine strip along the front or middle of you're shelves, old skids work good run them threw a planner and then rounded of with a router it will allow you to hang stuff of them and it will prevent the shelves from sagging.

plywood will also sag and is not the best to make shelves out of either I Would use the mdf or go to a soft wood (pine ect) panel it will be very solid and will last many years to come and will look very good when stained

A firing strip is a 1/2x1.5 inch pice of wood used used for framing a cement wall to install drywall or that fake wood type panel stuff to the wall. You ancor the wood strip to the wall then srew or nail the finishing material to the wood strip. it is cheap framming for basement's that have no wood frame

 

[cc_rider]

I've found MDF is pretty lousy over time. BUT there's a trick you can do to make them stronger and nicer looking. Get a stick (10') or two of extruded aluminum 'C' channel of the correct thickness; I think Home Depot has the right size. Cut to the length of your shelf and shove it onto the outermost edge. Cleans up the edge and adds a ton of strength.

MDF (or any particle-type material) loses it's strength over time and exposure to moisture. Plywood is better since it has oriented strands. For shelves, I'd never use anything less than 3/4" veneered plywood. The veneer adds a pinch of strength and guarantees a smooth surface. Best to seal them with poly or some kind of sealer/finish before you load them up.

Another way to make MDF pretty strong is to laminate Formica (countertop laminate) onto it. If you do BOTH sides you get a darn strong board! That's a long way to go.

c.

 

[wilbilt]

what is a "firing strip"?

I think the intended term is "furring strip"

i.e., a 1x2 board.

 

[the intimidator]

well at least somewon knows the correct term

 

[MXtras]

I pretty much agree with everything said so far - MDF has advantages over plywood, but I have found plywood stronger overall. Some may dissagree but that's my general observation. If I have a simple box made from plywood and it falls out of the bed of a truck, it's more likely to stay together than an equivalent box made from MDF.

I have seen MDF sag and I have seen plywood sag - the recommendation to reinforce with something is a very good idea - whether you use MDF or plywood. Ccrider's suggestion is what I would do - the aluminum would look nice and add a lot of support.

Countersinking - I will sketch up what I am talking about and post up a pic in just a bit - I am at work and things are busy at the moment.

Scott

 

[fenderwasher]

I have used both MDF and plywood for years for shelving. Both have worked well, with a one difference. Compared to plywood, you need to use more support brackets with MDF. For an 8’ long MDF shelf I’ll use 4 brackets evenly spaced compared with just 3 for 8’, ¾ inch plywood shelf. Any shelving material will sag if it’s not properly supported and I think MDF gets a bad rap for sagging but I find if it’s supported well it will last for years.

Also, don’t use wood screws, they ****. They are shaped like a wedge and will split the MDF. Instead use sheet metal screws. The have an aggressive thread which will provide a good bite and are straight shafted so they don’t act like a wedge when screwed in, like wood screws do. Always pre drill your holes before screwing. Use a drill bit 2 sizes smaller than the screw size.

Finally, keep in mind that one 4 x 8 sheet of ¾ MDF weights 96 pounds. Get help when lifting it. Whenever I buy the stuff I have the lumber yard rip it down for me to the rough sizes I need and then I’ll fine tune when I get home. It’s much easier on your back. If I buy it at my local Home Depot they’ll give me one free rip and then its 50 cents for every rip after that. Money well spent.

Good Luck.

 

[dboat]

good advice

I have used both MDF and plywood for years for shelving. Both have worked well, with a one difference. Compared to plywood, you need to use more support brackets with MDF. For an 8’ long MDF shelf I’ll use 4 brackets evenly spaced compared with just 3 for 8’, ¾ inch plywood shelf. Any shelving material will sag if it’s not properly supported and I think MDF gets a bad rap for sagging but I find if it’s supported well it will last for years.

Also, don’t use wood screws, they ****. They are shaped like a wedge and will split the MDF. Instead use sheet metal screws. The have an aggressive thread which will provide a good bite and are straight shafted so they don’t act like a wedge when screwed in, like wood screws do. Always pre drill your holes before screwing. Use a drill bit 2 sizes smaller than the screw size.

Finally, keep in mind that one 4 x 8 sheet of ¾ MDF weights 96 pounds. Get help when lifting it. Whenever I buy the stuff I have the lumber yard rip it down for me to the rough sizes I need and then I’ll fine tune when I get home. It’s much easier on your back. If I buy it at my local Home Depot they’ll give me one free rip and then its 50 cents for every rip after that. Money well spent.

Good Luck.