Planer improvement?

[Josh Doran]

So I had a thought. Wanted to see what others thought about it. Lunchbox planers are notorious for sniping.
Usually the cause is not enough support. As a longer board is inserted, the single roller may cause the board to tip into the blade resulting in snipe. What if 2 extra rollers were built into the planer, each one closer to the cutterhead. I don't know what kind of room there is available, so can't say if this is even possible. I can see 2 benefits. It would provide two points of contact before and after the cutterhead which might reduce the pivotting of the board into the cutterhead. Also it would allow shorter boards to be planed. Thoughts?

[Mike Heidrick]

An adjusted planer does not have snipe - no matter what the size machine. Has zero to do with the machine being a lunchbox. Learn to adjust your planer correctly.

[Metod Alif]

Double rollers on both, in-feed and out-feed sides would help and would need less pressure. Single rollers need more pressure (using stronger springs). Light cuts - less pull of the stock into the cutter head direction. Prevent movement into the cutter head and you cannot have snipe. Manually springing a board on both sides is a good 'external' remedy A well tuned planer is a must, but might still have 'internal' limitations, such as weak springs.
Best wishes,
Metod

[glenn bradley]

Mike speaks true. If you cannot adjust a small planer (assuming it is capable of proper operation) then buying a different planer won't help. There are some models that are notoriously poor and some even require after-market foolery to get them to perform as they should. Certainly proper stock support yields a better result but, that is true for many operations and should be assumed ;) You can't make a silk purse out if sow's ear but, any planer that isn't total junk can be setup to run snipe-free. There is an element of technique to the operation as well. Simply stuffing material in one end and catching it at the other will result in a milling quality equal to the care taken in the operation. :)

[Alan Bienlein]

This might help to explain the two types of snipe with these planers.

https://www.youtube.com/watch?v=XdDo3OEtjhc#t=385

[Dave Cullen]

An adjusted planer does not have snipe - no matter what the size machine. Has zero to do with the machine being a lunchbox. Learn to adjust your planer correctly.

Please define "adjusted correcty".

[Richard Coers]

A "real" thickness planer has an infeed top roller and infeed bed roller, both powered. The wood then sees a chip breaker in front of the cutter head and a pressure bar close behind the cutter head and then the out feed rollers. Yeah there could be improvement on the lunch box planers, but they would cost $2,000. The expense would save a couple inches on each end of each board.

[Dan Hahr]

An adjusted planer does not have snipe - no matter what the size machine. Has zero to do with the machine being a lunchbox. Learn to adjust your planer correctly.

That's a bold statement. I would love to know how to perfectly adjust my planers so that they never snipe the slightest bit. I have a DW735 and a 15" Delta. I have them adjusted as well as I believe they can be, but who am I to know for sure? The fact that the OP is referring to lunchbox planers does matter. Their sheer lack of mass, weight, and strength leads to the possibility of snipe. It doesn't mean it will all the time, but it is likely that a high end, 500 pound beast of a planer will be less likely to snipe, considering a lack of human error in feeding the board.

Snipe occurs when the leading or trailing end of a board is lifted into the cutterhead due to it being supported only in the front or back. This fact is dependent on many factors including the thickness of the board, the flexibility of the board, compressability of the board, the stability of the framing of the planer, locking ability of the cutterhead or bed, flexibility of the cutterhead, stiffness of the feed roller springs, , and manner in which it it fed into and out of the planer. A heavy duty planer that is properly adjusted will be much less prone to snipe than a lightweight cheapo planer that is properly adjusted.

Properly adjusted, all planers can snipe if the board itself allows it. You might not notice it without dial calipers or a coat of varnish viewed in the right light, but I'd like to know if you mean no snipe, as in ZERO, or relatively insignificant snipe.

OP, yes, it would help, possibly a lot, but not completely eliminate the possibility of snipe. However, it would go against the new American way of making things as cheaply as possible.

Dan

[Art Mann]

I use a lowly Ridgid lunchbox planer and it does not snipe, at least on moderate size work pieces. If the work is very long, I will hold it up above the in-feed surface table just a little bit. I occasionally measure it with digital calipers and it is 0.005" or less, which is about as accurate as that planer will plane a surface anywhere. The instructions that came with the planer said to elevate the outer edges of the in-feed and out-feed tables using the thickness of a dime as a place to start. It worked for me but I don't think that is universal. The worst snipe I have ever seen is on large commercial planers and it one reason I prefer to machine my own stock.

[Charles Coolidge]

Snipe occurs when the leading or trailing end of a board is lifted into the cutterhead due to it being supported only in the front or back.
Dan

Feed 3 boards end to end into a planer, the first board will have snipe at the front, the middle board will have no snipe, and the last board will have snipe at the end. In your example all three boards would have snipe at both ends which is not the case. Snipe seems to be more related to load, less than full load as the first board enters and less than full load as the last board exits, you can feed 100 boards through in the middle of the run end to end with no snipe. Just my observation.

[Rod Sheridan]

I guess I don't have a real planer, mine doesn't have bed rollers, which doesn't affect me as I only plane jointed material.

My planer has been adjusted for zero measurable snipe.

The issue with snipe is twofold

- lack of strength of the planer mechanism, allowing the planer to flex or allowing the wood to tip while oonly being driven by one roller

- out of adjustment rollers, pressure bar or chip breaker.

Regards, Rod.

[Phil Thien]

Feed 3 boards end to end into a planer, the first board will have snipe at the front, the middle board will have no snipe, and the last board will have snipe at the end. In your example all three boards would have snipe at both ends which is not the case. Snipe seems to be more related to load, less than full load as the first board enters and less than full load as the last board exits, you can feed 100 boards through in the middle of the run end to end with no snipe. Just my observation.

Your technique is similar to mine. I actually run the 1st board through after the last board, just turn it around so the snipe is at the end, and voila, you only have snipe at one end of the first board, none of the other boards have ANY snipe.

My Dewalt DW734 produces very nominal amounts of snipe, but when you are working with shorter boards (as I often am), a little snipe on the end of each one quickly adds up. So ganging them and then reversing the first board for a 2nd pass as I've outlined above is a real materials saver.

Are you related to our 30th president?

[Phil Thien]

The issue with snipe is twofold

- lack of strength of the planer mechanism, allowing the planer to flex or allowing the wood to tip while oonly being driven by one roller

- out of adjustment rollers, pressure bar or chip breaker.

Regards, Rod.

Yep! Even the lunchbox units that have a cutterhead lock (such as mine) still just aren't beefy enough that they can withstand the leverage of a thicker piece of material. The cutterhead locks reduce the snipe, but I don't think they will ever eliminate it.

[Steve Baumgartner]

Yep! Even the lunchbox units that have a cutterhead lock (such as mine) still just aren't beefy enough that they can withstand the leverage of a thicker piece of material. The cutterhead locks reduce the snipe, but I don't think they will ever eliminate it.

+1 The key to the problem is leverage, although I would say "longer" rather than "thicker", since the center of mass of a long board is farther from the support table and has a greater lever arm against the rollers in the planer. This leverage can flex the machine or compress the rubber rollers enough to cause snipe. So, better support of the stock is your first option. Lifting the trailing end as the board enters, and the leading end as the board leaves the planer will reduce the leverage and reduce snipe.

But some lunch boxes are so flexible that they will bend due to the uneven pressure when the wood is under one roller but not the other as the wood enters and leaves the planer. In that case the best cure, as noted earlier, is to feed a sacrificial piece of the same width before and after the "keepers". Using the same width is important, since pieces of different width will press against more or less of the roller and that will still produce an uneven pressure - less so, but still there.

[Charles Coolidge]

Your technique is similar to mine. I actually run the 1st board through after the last board, just turn it around so the snipe is at the end, and voila, you only have snipe at one end of the first board, none of the other boards have ANY snipe.

My Dewalt DW734 produces very nominal amounts of snipe, but when you are working with shorter boards (as I often am), a little snipe on the end of each one quickly adds up. So ganging them and then reversing the first board for a 2nd pass as I've outlined above is a real materials saver.

Are you related to our 30th president?

Yes actually our family is related to Calvin Coolidge, pretty cool.

[Charles Coolidge]

By the way even industrial CNC machines flex, your talking 10,000 to 14,000 pound beasts. Take a heavy cut with a CNC lathe, then repeat that cut with the exact same settings and it will remove more material that wasn't removed on the first cut.

[Phil Thien]

+1 The key to the problem is leverage, although I would say "longer" rather than "thicker", since the center of mass of a long board is farther from the support table and has a greater lever arm against the rollers in the planer.

Agreed. But the thinner boards (1/2 or 3/8 and thinner) will flex some, thicker boards require the mechanism that moves the head to flex.

[Prashun Patel]

Sorry Op, that your theoretical question got a lot of accusations about your technique. I agree with Metod and Dan that it would with help but not eliminate the snipe. I also believe that it's straightforward idea that must factor into the designers' mind. The fact that most lb planers are designed the same way suggests it's been considered and dismissed before.

IMHO, (and I bet Archimedes'), the leverage is easiest counterbalanced at the extreme points of infeed and outfeed. For thick stock, when I can't use 1ft longer stock, I use a sled.

Caveat emptor on this (I have not yet tried it): For thinner stock, i heard a neat tip on FWWShoptalk whereby you feed in the thin stock in, and bend it upward as dramatically as you can stomach until the piece contacts the cutterhead. Then you lift it similarly on the outfeed.

[Dan Hahr]

You are correct about your method of eliminating snipe. I believe it is the absolute best way of doing so. However, I think it is due to the fact that the friction of the end to end contact is holding each end down.

To illustrate, try doing so with a 1/4 inch gap between the boards.

Also, Rod, as far as measurable snipe goes, what are you measuring with?

Art, 5 thou is not that bad, but it does sound like snipe.

Mine snipes around .003 on 3/4" material but it is observable and is snipe.

Dan


Feed 3 boards end to end into a planer, the first board will have snipe at the front, the middle board will have no snipe, and the last board will have snipe at the end. In your example all three boards would have snipe at both ends which is not the case. Snipe seems to be more related to load, less than full load as the first board enters and less than full load as the last board exits, you can feed 100 boards through in the middle of the run end to end with no snipe. Just my observation.

[Josh Doran]

Thanks for the replies. Interesting info. I had been feeding the boards by tipping the ends as they entered and left. Still got snipe but less so. My main frustration
was that the boards were coming out with a hump in the middle. I thought the snipe was causing this as the board was flipped over each pass. This is especially frustrating after hand planing one side true then getting it mangled in the planer. I recently took the wings off to try out some torsion boxes I made to replace them. I measured the bed with a straight edge and discovered the bed was humped in the middle. This wasn't noticed when I first set up the planer as my straight edge was longer than the bed and so also touched one of the wings. I've sent the planer to repaired. Hopefully this fixes things.

[Guy Belleman]

Having used lunch box planers for years, I found that adjusting the infeed and outfeed tables perfectly with the inside bed almost impossible. After using the technique of putting a smooth surfaced board, hooked over the end of the infeed table and the board going all the way through, boards had no snipe and almost always turn out perfectly. Good luck.

[Myk Rian]

I find that my DW735 produces some snipe when it's cold.
Seems the rollers get hard, and bump the head a bit.