Thursday, October 25, 2012

V3.42 - Yes, a ‘snipe hunt’ is a real thing.

Ok, so we’ve talked about planers, what they will do and what they won’t...what causes the biggest problem (and it really is a simple solution). Now this time, we get to talk about one of the biggest pains in the you-know-where.

This week I’d like to introduce you to one of the most frequent problems of a planer. Snipe. Yes, it really IS called that…among other things. The basic symptom is that after the board has been run through the planer, the thickness of the ends is thinner than the middle of the board. Remembering that the purpose of a planer is to make the board the same thickness in all areas, Snipe is not an acceptable outcome.

Snipe can also be known as ‘cut out’; ‘dip out’; ‘notching’- names like that.

Essentially tho, one looks at the board surface and sees where, for the first few inches and usually the last few inches, the knives have made a deeper cut than they do on the rest of the board. For the purpose of our discussion, we’re going to limit ourselves to lunchbox planers that do not have bed rollers. [Bed rollers, which are mostly found on industrial planers. create other situations that we aren’t ready to talk about].

Alright, so you’ve sent a board thru and you see and feel snipe on the ends of the board. The first thing to realize is that this is being caused by the head of the planer rising as the board gets underneath both feed rollers. Again, we’re talking about lunchbox planers that usually are pretty simple- they have a fixed bed and a movable head. The head moves up and down to adjust the thickness of the cut.

So what happens- as the board is placed on the bed and pushed into the planer, the infeed roller grabs it and pulls it in, about 2 inches into the planer, the board runs underneath the knives and starts being cut. About 2 inches after that, the board runs underneath the outfeed roller and starts being pulled by both rollers, AND this is where the snipe stops… on the front end of the board. As it comes out, it leaves the infeed roller and snipe starts on the trailing end of the board. In this case you would have a 2” snipe on each end of the board.

Lots of background I know, but knowing the basics is essential to knowing why snipe occurs and what to do about it…and that we will do next time.

Send your questions or comments to: and we’ll see what we can do to help you.

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