Replies

1. 
   stevemorris | Dec 28, 2008 03:48pm | #1

   you'll have two issues here

   first of all, never joint the faces of a laminated material like plwood,mdf or particle board, the piece probably will peel apart.  edges yes no problem exept that the grain in plywood is half end grain on the edges and wont joint very well

   second is the dust especially from mdf, its nasty stuff.  if i can, i machine it outside

   a decently tuned table saw will cut sheet goods perfectly with a good blade so really a jointer isnt needed any way, i just use an old portable table saw i keep in the shed or my work truck for particle board or mdf and use it outside for that stuff

   the other option for those sheet goods is an edge guide system and a circ saw, again a well tuned saw witha decent blade and the edge guide, you'll get a perfect straight cut

   and a final note, i dont use mdf for jigs and templates, hate the stuff, that 3/4 paint grade maple plywood from home depot is much better and you can machine it inside

1. 
   marty52 | Dec 28, 2008 08:33pm | #4

   Thanks Steve.  I only did the plywood and MDF edges and I noticed the MDF dust right away. 

   I used MDF for the base of a crosscut sled because it was flat; the pieces of plywood I got from Home Depot were not.  I am trying to flatten them with weights.  I have also read that Baltic birch plywood is also used often for crosscut jigs and maybe for larger jigs in general.  I have not located a supplier of 2x4' or4x4' sheets in my area (near Philly) yet.

   Thanks again,

   Marty

1. 
   RalphBarker | Dec 28, 2008 09:03pm | #5

   Most Home Depot and Lowes stores carry Baltic Birch ply in small "handy" panels. Look near their "premium" pine and poplar section.Be sure to check it for flat, however.Another option for jigs is Phenolic ply (1/2" or 3/4") from Woodcraft. Just wait for a free shipping special.Edited 12/28/2008 1:04 pm by RalphBarker

   Edited 12/28/2008 1:06 pm by RalphBarker

1. 
   northhouguy | Dec 29, 2008 12:21am | #6

   Previous threads on this forum have indicated that a lot of plywood from the Big Boxes is Chinese junk. 

   Reported problems include warping, de-laminating and voids.  Buyer beware.

2. 
   hammer1 | Dec 28, 2008 04:09pm | #2

   Jointing plywood or MDF will just beat up your knives, very quickly. If you can't cut it straight, you should work on that. Either that or get real good at sharpening and changing knives.

   Beat it to fit / Paint it to match

1. 
   marty52 | Dec 28, 2008 08:26pm | #3

   Thanks Hammer.  I'll joint some solid wood and use that on the saw to get a straight cut for the plywood or MDF.  Sound reasonable?

   Marty