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Yea, just not in English you can understand.
Is some planer snipe to be expected?
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Your graphic doesn't accurately explained it to me. If it did, every board I run through my planer, heavy or light or long or short, would have snipe. That simply is not the case. short light boards go through without snipe and without any assistance of any kind.
With long heavy boards, you've got to do both.
No one that advocated "lifting the board" is talking about lifting the infeed end. Of course, that would be problematic. The object is to take the weight off of the trailing end in order to keep the infeed end in contact with the planer bed as the feed begins.
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By lifting the tail end, you're adding extra spring force to the first roller so the head is stressed the same amount it will be when the second roller catches it and you let the board lay flat. I'm done.
So. When you are on the seesaw and you go up your playmate on the other end goes up with you? Interesting seesaw you have.
As as been stated several times, the idea is that you put upward pressure on the tail end of a heavy board so that it's weight doesn't lever up the infeed end so that it is lifted off the planer bed as it pivots on the edge of the bed or infeed table. If the upward force on the infeed end is more than the first roller springs can overcome, it will raise the first roller more than it should and hit the knives on high and cause some snipe until you or both rollers can push it back down (by lifting the other end).
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If you have a system that works all the time, keep doing it! After 10 yrs. and knowing my machinery, I do too. What I have tried to simplify is what I do every time in every situation, and it always works. Just because most woodworkers use this system doesn't mean you have to. I fitted instrument tubing for a living for about 20 yrs. There's one facet it has in common with woodworking:
'If you screw it up, you throw it away.' You don't do that when 1/2" tubing is $30/ft. I found a system that worked for me, and no two fitters worked exactly the same, but we strived for excellent results. The same is true for woodworkers.
I agree with you 100%. But, that doesn't help to clear up the misunderstanding as to which end is being lifted and the reason for it; all for the purpose of helping the OP answer his question.
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No, I believe he was politely telling you you don't have a clue and he's not going to argue with you any more. Well, that's my guess.
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I watched Google's leading video on the subject. The guy doing it doesn't know what he's talking about and is confusing a lot of people. Given the wood is fed flat into the planer, it will always have snipe. It has nothing to do with coming in nose up or down. It's caused by the feed roll springs pushing up on the planer head in sequence with the cutterhead between them. If the first roll spring exerts 100lbs upward on the head, the wood goes under the cutter, then the second roll exerts another 100lbs on the head, the head moves an extra distance under the extra 100lbs of force exerted on it. Don't EVEN think that extra 100lbs. of stress on the head doesn't move it, especially if it's a stationary table planer where the roller springs have to support the head during planing. The difference in movement between the first and second rolls' upward pressure creates the snipe. It has nothing to do with you, see saws, or anything else."My opinion has not changed, nor the fact that I'm right."
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[EDIT] I read a few articles on the subject, and the cutter head lifting is only mentioned on small planers. They contend a locking head will prevent the problem. Every other article talks about feed roller pressure and how close to cutterhead. Explains why lifting a board works, but doesn't explain how feeding another board right behind works - that seems supported by the lifting cutterhead idea.[/edit]
Its a really interesting discussion but the physics still escape me - relative to a cast iron planer. I'll take what you guys say as a fact, even though I still can't understand how a roller head mounted in a cast iron head is going to flex upward. I'm trying to correlate to using a hand plane but can't.
As I mentioned, I get zero snipe on my planer. I attribute this to the fact it has a pressure bar which I believe most planers do not have, correct me if I'm wrong.
It also has bed locking knobs, which I never use, and I'm not aware of many planers that have them. I have seen my height adjustment wheel rotate as wood goes through on a heavy pass. It has never done this before the last year. For me, I take that (plus noise) as an indication the blades are dull, but also seems to support what Rick is saying.The blades are WAY over due.
So question: does blade sharpness come into play? Seems like there would be less down force if the knives are sharp.
What I do know is a long board hanging off the outfeed will have snipe regardless, and when planing thin stock a slight uplift on both infeed and outfeed eliminates issues. I had some snipe, but lowering the bed rollers below the bed totally eliminated it. Me, my planer, and 20 years experience using it.
So I think there are a few causes of snipe, maybe all of us are right in one way or another. In the end, all that matters is good results, not understanding why you're getting them?
Newer version of my machine:
![Gas Motor vehicle Engineering Machine Machine tool]()
Its a really interesting discussion but the physics still escape me - relative to a cast iron planer. I'll take what you guys say as a fact, even though I still can't understand how a roller head mounted in a cast iron head is going to flex upward. I'm trying to correlate to using a hand plane but can't.
As I mentioned, I get zero snipe on my planer. I attribute this to the fact it has a pressure bar which I believe most planers do not have, correct me if I'm wrong.
It also has bed locking knobs, which I never use, and I'm not aware of many planers that have them. I have seen my height adjustment wheel rotate as wood goes through on a heavy pass. It has never done this before the last year. For me, I take that (plus noise) as an indication the blades are dull, but also seems to support what Rick is saying.The blades are WAY over due.
So question: does blade sharpness come into play? Seems like there would be less down force if the knives are sharp.
What I do know is a long board hanging off the outfeed will have snipe regardless, and when planing thin stock a slight uplift on both infeed and outfeed eliminates issues. I had some snipe, but lowering the bed rollers below the bed totally eliminated it. Me, my planer, and 20 years experience using it.
So I think there are a few causes of snipe, maybe all of us are right in one way or another. In the end, all that matters is good results, not understanding why you're getting them?
Newer version of my machine:
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Just as a forenote: I've seen a 16" metal lathe with a 1" shank threading tool flex 10-15 thousandths when cutting regular 8 pitch threads. Cast iron is strong, but it will flex.[EDIT] I read a few articles on the subject, and the cutter head lifting is only mentioned on small planers. They contend a locking head will prevent the problem. Every other article talks about feed roller pressure and how close to cutterhead. Explains why lifting a board works, but doesn't explain how feeding another board right behind works - that seems supported by the lifting cutterhead idea.[/edit]
Its a really interesting discussion but the physics still escape me - relative to a cast iron planer. I'll take what you guys say as a fact, even though I still can't understand how a roller head mounted in a cast iron head is going to flex upward. I'm trying to correlate to using a hand plane but can't.
As I mentioned, I get zero snipe on my planer. I attribute this to the fact it has a pressure bar which I believe most planers do not have, correct me if I'm wrong.
It also has bed locking knobs, which I never use, and I'm not aware of many planers that have them. I have seen my height adjustment wheel rotate as wood goes through on a heavy pass. It has never done this before the last year. For me, I take that (plus noise) as an indication the blades are dull, but also seems to support what Rick is saying.The blades are WAY over due.
So question: does blade sharpness come into play? Seems like there would be less down force if the knives are sharp.
What I do know is a long board hanging off the outfeed will have snipe regardless, and when planing thin stock a slight uplift on both infeed and outfeed eliminates issues. I had some snipe, but lowering the bed rollers below the bed totally eliminated it. Me, my planer, and 20 years experience using it.
So I think there are a few causes of snipe, maybe all of us are right in one way or another. In the end, all that matters is good results, not understanding why you're getting them?
Newer version of my machine:
View attachment 449630
It looks like everything you've conveyed is correct to my knowledge. I'd like to add that feeding a scrap at both ends merely fools the planer into thinking it's got one board instead of three, thereby transferring the snipe from your stock to the scrap. Just make sure both dummies are longer than the minimum length required by the planer. Dull knives are at the top of the pyramid as far as attention goes, and will cause all sorts of problems such as failure to or irregular feeding, excessive tearout, burnt surface, cracked or broken knife, damage to rubber feed roll or clogging of serrated roll, motor overheating, excessive drive wear, etc. Luckily your machine has micro adjusting screws under the knives, which makes shifting a nicked one to help get rid of 'road dirt' as Garrett Hack calls it, really fast so you can get better results longer. Keep them as sharp as your hand plane. After all, it's the same job!
I hope there's something below that you can find useful. You're doing the most important thing: always adequately supporting the stock at or slightly above level.
Your machine has almost everything built-in to eliminate snipe, NONE of which are found on portable machines as far as I know:
1) Stationary cutterhead that never moves for thickness adjustment, and being one-piece cast iron will flex very little (may not be measurable). Both these flex reducing features reduce snipe.
2) Bed rollers opposing the feed rolls allow the stock to feed on a roller instead of being pressed hard against the bed. This feature permits the feed roller springs to be 'slacked off' load pressure due to the absence of friction between the wood and the bed at the roller contact point (looking at a side view), thereby reducing flex in the head and its associated snipe. These rollers have to be precisely adjusted.
3) Heavy cast iron locking bed may be the most snipe reducing feature. A strong bed that doesn't flex under roller spring load and locks in place to eliminate any backlash or thread stress in the height adjustment screws and columns provides rock solid support.
4) Your pressure bar actually serves two functions: Both help to reduce snipe and ensure consistent results.
a) It 'preloads' your stock to ensure a flat feed coming in
b) It lessens the delta between the two feed rolls to further reduce the flex in the head due to that delta.
High end industrial machines have other high production and long use lifespan features such as segmented rollers, wedge beds, etc, but the high cost of including those is prohibitive for most users.
The ONLY drawback to your design is having to adjust the long stock roller stands as the thickness of the stock changes. Maybe somebody can come up with a wireless laser transmitter on the planer that will adjust both Li-ion battery powered stands automatically.
Your last statement sums up everything I said previously.
You should be proud of what you have! It's a good machine. My brother-in-law had one like yours, but had to sell it when he moved because of a job relocation. I didn't have room for it, either.
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That ain't much. I'm almost 70.
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It is! Somebody has to pick up the shortfalls of our public school system failures. Namely, the lack of logical scientific thinking. Oh well!
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