What is LDF???

[jay tomaka]

i went to the home depot and they have no ldf? they have MDF but no ldf. does it go by another name?? need it for my top spoil board of a vacuum system. thanks

[Donna]

Jay,

If you contact Georgia Pacific Distributors they can tell you where your local distributor is. You will probably have to purchase it in a unit.

Donna

[davenadeau]

Jay,

Low density fiberboard is available, but is certainly rarer than MDF, so Home Depot may not stock it or may only occasionally stock it. Your local hardwood/plywood/cabinetry supplier may stock small quantities of it or sell it on a special-order basis. If you are seeking it to make large quantities of parts out of it, then Donna's suggestion to contact GP directly is probably the way to go for large quantity. If you are seeking it to make a vacuum system bleeder board, then you presumably only need a few sheets at most instead of an entire unit. I've bought individual MDF sheets (for use as a ShopBot spoilboard) along with entire units of plywood from a local hardwood/plywood supplier. They usually shipped the MDF and plywood units together to me, but the only reason they shipped to me at all was because the 30-sheet units of 31/32" plywood were worth about $1200 each. I don't know how many sheets of LDF are in a unit, but if a unit of LDF is about the same as a plywood unit and you need only a sheet or two for your vacuum table then the cost may be prohibitive.

If LDF is unavailable or cost-prohibitive, I would use 1/2" MDF. Since MDF has a dense, smooth, less-porous surface on both sides relative to the center, you can fly-cut both sides of it to reveal a relatively low density core that is much more porous to air flow than intact MDF. After adjusting your Z axis to get the bit as plumb as possible, suck a sheet of MDF down on your plenum, then fly-cut the upper surface of the MDF to remove about 1/16" to 1/8" of the upper surface. Be sure to start with an empty dust collector, and consider pausing 1 or more times to empty the collector during cutting if necessary. You may also want to use duct tape or something similar to temporarily seal the gap between MDF and plenum to keep dust out and vacuum in. After fly-cutting the upper surface the MDF will probably have a strong bow in it, so keep the vacuum on to keep it sucked down while you clean up remaining dust with a ShopVac (this will keep stray dust from going into your vacuum plumbing). Flip the sheet, suck it down again, and fly-cut the other side...

David Nadeau
Technical Support
ShopBot Tools