# Correct Jointer Technique



## Hawgnutz (Mar 29, 2007)

I thought a jointer is supposed to give you a flat surface to referrence on to get all 4 sides surfaced flat. I tried to get a flat surface tonight on a face of 1/2" MDF. The ends were noticably thinner than the middle. Am I doing something wrong? I used a pushblock on the feed table all the way through. 
Am I, inadvertantly, putting pressure on outfeed side? 
Just what is correct use of a jointer. I just got a used one two months ago and I am still learning it.

Thanks for your insight.
God Bless,
Hawg


----------



## cajunpen (Apr 9, 2007)

You MUST put pressure on the *Outfeed* side. It sounds like you are putting pressure on the Infeed side, close to the cutters. What you need to do is put pressure (using your push blocks) on the end closest to the cutters. As soon as that end clears the cutters, switch your left hand over to the Outfeed side and continue putting downward pressure on that side (Outfeed) ONLY. I switch both hands to the outfeed side as soon as I can.


----------



## MsDebbieP (Jan 4, 2007)

one of the Wood Whisperer's first podcasts demonstrates using the jointer … video is always helpful.


----------



## Kaleo (Jan 25, 2007)

Mdf is known to bow amd move after you remove the outer skin. To be honest you should have to put MDF through your jointer to get a flat face. It should be flat already. Plus man made boards like MDF and Chipboard are full of abrasives and will blunt your jointer blades really fast.

As for technique, it's been said that you shold put the pressure on the outfeed side of the blade. If you put to much pressure on the infeed table you will plane the surface and it will be the same as before. I reckon your problem is that your outfeed table is not lined up with your blades, thus giving you an uneven cut. Try setting up your outfeed table to the exact same height as your blades.


----------



## Chipncut (Aug 18, 2006)

*Also make sure all of your blades are set to the same height.*


----------



## coloradoclimber (Apr 7, 2007)

It sounds like everyone has already nailed it but to reiterate, the pressure goes on the outfeed table. You set your outfeed level with your knives, you start the board across the knives, as soon as there is enough wood on the outfeed table to get a good grip with your push blocks you move all your pressure to the outfeed side, basically dragging your wood from the infeed across the knives.


----------



## Hawgnutz (Mar 29, 2007)

Kaleo, I know that the face of my MDF was flat, but I needed to change the thickness from 1/2" to 3/8". I do not have a stand for my planer, yet, so I was using my jpointer.

I made sure thath the outfeed table was even with the blade heighth befiore I cut. I was just unsure of the proper technique. It made sense to keep pressure on outfed, but I was keeping pressure on infeed. OOPS

I only needed about 30" length and 4" wide to go through the jointer, so I hoped that the blades would hld up. I plan to hone the blades soon. I am getting a new caliper gauge to measure the blade height.

Thanks for all the feedback!
God Bless,
Hawg


----------



## MikeLingenfelter (Feb 19, 2007)

Keleo is right MDF can bow very easily. I've never try to plane MDF before, but if changing your technique doesn't work. Try attaching the MDF to another piece flat and stiffer wood, so it doesn't flex. Some double stick tape should work. I'd also use long strips of tape so that it won't flex between the tape.


----------



## Hawgnutz (Mar 29, 2007)

that attaching MDF to a stiffer board seems like teh way to go! I hate to plane or joint it cause it tears up the blades, but sometimes you gotta wht ya gotta do!
Thanks for all the info!

God Bless,
Hawg


----------



## MikeLingenfelter (Feb 19, 2007)

I bet it chews up the blades. I did a little hand planing on a piece of MDF to tweak the fit once. I lost my cutting edge pretty fast.


----------



## misch (Aug 11, 2007)

Also, you mentioned you bought your jointer used. It's possible the infeed and outfeed tables aren't "coplaner." Even though they operate at different levels, the infeed and outfeed tables should be on the same plane with one another. A drastic example would be to imagine a "U" shaped infeed and outfeed table. As you feed your wood in, it takes some off the leading end and hits the outfeed table where it slopes upward, missing the center section with the blades and finishes on the tail end by hitting the blades again. Search online under "coplaner jointer" for a better explanation and resolution. Hope that helps.

-Steve


----------

