MDF or Particle board ?

[JackG]

I am considering building some sort entertainement unit essentially composed of boards, some will be Melamine some veneered.
I have used MDF and Particle boards on other occasions and have found that the MDF tends to sag a little more than particle boards. Is it a fact ? did I just get poor quality MDF ?(it was rather cheap) Would you rather use one or the other for this application ?

Also while I am at it, where is a good place in Sydney to buy Black melamine boards and MDF/Particle boards veneered ?

Cheers

[craigb]

Dont know about black melamine, but Brims sell venerred particle board.
www.brims.com.au

As far as the sagging of MDF goes, check out The Sagulator
http://www.woodworkersweb.com/sagulator.htm

[Kev Y.]

Jack, because MDF has no grain structure, it will tend to sag if used as shelving, especially if the shelves are over 1m in length.

To over come this you could use some 50mm X 25mm pine as a strengthener under the back and front of the shelves.

IF You are using the MDF as a vertical partition, one way of controlling the sag effect would be to make several smaller partitions and stack them to the height you require. OR you could from the edges with a strip of hardwood or pine.

[Dion N]

My father in law has been a cabinet maker for 40 years. He would never even think about using MDF instead particleboard. Particleboard is stronger and better resists moisture.

I would suggest going to the Laminex Group website and downloading their "Tradesman's Guide to Whiteboard", which will give you shelf loadings for various thicknesses and spans of particleboard.

[Ticky]

Jack, I am wondering if you have concidered using real timber as opposed to manufactured sheets for this job. You probably would have to join boards to get your shelf width, but apart from that, is there an advantage to using sheet products over timber?

ticky

[Skew ChiDAMN!!]

MDF has it's place. When building something you want to be proud of, that's not it. QED.

[JackG]

Thank for the info, it confirms what I was thinking that the particle board is more suited.

Ticky,
I have and still am considering real timber, the cost of course is an issue, I am looking at about 3-4 m2 of timber. I do have enough timer I got trough the BB from that $100 pack bonanza (thanks again) but I wonder if I want to use it for that. Another issue is the seasonal movement, the base will be 3000mm long and I am a bit worried that I wont be able to open the doors and drawers in summer.
I am not really excited about this project, it something I have to do, I rather do joinery than work with boards but hey ! I have to justify the toys in the shed.
Anyway I broke my wrist a few weeks ago and I still have a few more weeks before I can do anything in the shed, just doing plans and getting the stuff ready.

Thanks for the feedback

[mkemila]

[quote=Dion N]Particleboard is stronger and better resists moisture.

Really depends on the application and the type of MDF purchased......I hate both evenly, but have used MDF on my router table top because of its densityCheers