Re-Sizing Glued Planks of MDF

  • Advertise with us

« back to Wood & Lumber forum

Forum topic by HorizontalMike posted 11-26-2011 07:00 PM 1532 views 0 times favorited 5 replies Add to Favorites Watch
View HorizontalMike's profile


7756 posts in 2911 days

11-26-2011 07:00 PM

Topic tags/keywords: horizontal mortising machine mortiser fixture jig horizontal router mdf glue up

I am starting a project to build a horizontal mortising fixture/jig. While gluing up a stack of three 3/4in MDF panels (2 at a time), I found it near impossible to get a perfectly aligned glue-up. I adjusted for that possibility by over-sizing the pieces, but now wonder about the “Best” way to square and re-size these MDF stacks. FYI, I used TiteBond III glue.

My question centers on the possibility of gunking-up any of the following cutters when squaring and sizing these MDF stacks:

TS w/50T Freud Combination Blade

Jointer w/helical cutter

BS w/half inch 4TPI

Not really expecting problems here, but I do remember when I once cut up some PVC on the BS and had a grand old time peeling the melted PVC from the blade. ;-)

-- HorizontalMike -- "Woodpeckers understand..."

5 replies so far

View jim C's profile

jim C

1472 posts in 3095 days

#1 posted 11-26-2011 07:11 PM

It sounds like you just stacked them, right? Not edge glued. If so, why joint them at all? assuming that you have only a small overlap, just butt the edge against your TS fence, true up one edge, flip it around, and true up the other.
The glue, if completely dry, shouldn’t gunk up the blade.

View HorizontalMike's profile


7756 posts in 2911 days

#2 posted 11-26-2011 07:19 PM

That is my original plan. I have heard/read bad things about jointing/planing MDF, as it tends to dull blades rapidly. And besides, the stack only comes to 2.25in thick and the 10in TS handles that with ease. The TS is also the easiest of the three to clean up if gunking does occur.

-- HorizontalMike -- "Woodpeckers understand..."

View Bill White's profile

Bill White

4929 posts in 3957 days

#3 posted 11-26-2011 07:21 PM

Don’t use the jointer. You’ll trash the knives. That stuff is really tough on knives. Wanna know how I found out?


View A10GAC's profile


191 posts in 3075 days

#4 posted 11-26-2011 07:47 PM

I glued up two layers of 3/4” MDF and topped them with a 1/8” layer of hardboard for the router table extension on my table saw; during the glue up I kept the layers flush on one edge and then squared everything to that with the table saw. I used a 60 tooth Freud Diablo that I picked up from HD and didn’t have any problems other than the insane amounts of dust that the saw generated. Fortunately the shop has a garage door so I just wheeled the saw out into the driveway. The shopvac/dust deputy combination barely kept up; being outside kept the residual out of the shop and my lungs.

-- Men have become the tools of their tools. - Henry David Thoreau

View HorizontalMike's profile


7756 posts in 2911 days

#5 posted 11-27-2011 01:16 AM

10-4 on the DUST! I started squaring off one of my 3-stack of MDF and even with the HF DC w/separator very fine dust just shot out and back at the operator (ME!). My Freud 50T Combo does not seem any worse for the wear, BUT, with this being my first MDF project it sure comes at a heavy price lung wise ;-)

Thanks for the input guys…

-- HorizontalMike -- "Woodpeckers understand..."

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics