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I recently had trouble trying to plane a block of maple on my 12" Makita planer. The block measured 12"L x 2 1/4"T x 8"W. I set the planer to remove just a fraction of wood, maybe 1/64th at most. A second after the first roller grabbed the wood I heard a quick but horrible sound of wood being pulverized. I ended up with terrible snipe across the first 1/2" of the block. The gouge was about 1/8" deep give or take. I've had a little snipe before but nothing like that. I'm guessing it was caused by the short length of the wood which allowed the front end to pivot up into the blade rather than stay flat on the table. Can someone verify this for me or give me an alternative explanation?
Probably due to the short length and perhaps lack of proper feed technique. Did you push the front end of the wood down against the table while holding up the bottom of the back edge of the board while feeding it into the machine? I have found that this helps to get the shorter pieces started through the planer while minimizing snipe.
Is this a portable planer? If the rubber feed rollers get worn, or are out of adjustment, they won't control a small part very well at a light cut setting. It generally helps to skew short parts diagonally to feed them.
I angle short boards when feeding them into my sub-par planer. That makes the effective length longer.
It depends on your planer, but typically there is a chip breaker right in front of the knife head that holds the piece against the bed plate. These chip breakers are spring loaded as they have to open different amounts depending on the thickness of the incoming stock. So, with very dry, dense wood, the knives will try to push the piece up against the chip breakers and often will win the battle. As soon as there is some wood fed past the head, then the pressure bar, which is fixed, will take over and hold the piece.
With longer lumber gravity and an unsupported end cause the front or tailing end into the knives and give snipe.
As mentioned, feeding at an angle works, as the small amount of wood going into the planer knives initially is not big enough to create a lot of force on the chip breakers, and then after an inch or so of feed, the pressure bar takes over and holds the piece against the end. If the PB is too tight, then the piece will not feed easily. If too loose, the piece will move and chatter. The PB should be adjusted initially so it holds the lumber, and then as the PB wears or the knives wear and are shorter, the PB again needs adjustment. The ability to make adjustments is what makes planers expensive...cheap planers give cheap results, especially after a little wear.
This is a short bit on a complex subject, so ask any questions