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Controlling snipe on a W&H8/9/17
We recently ran a large order (for us) of hard maple case and base. We struggled throughout the whole thing with snipe mainly on the out feed end of the cut but occasionally on the infeed as well (so we would have 6-8" of waste on each end of some pieces).
Hard maple is always a major b***h for us. I hate the stuff. We ran all this material in 2 and in some cases 3 passes but still fought it the whole way even on a 3 pass which seems ridiculous to me as it wasnt an overly deep profile. Perhaps 9/16" to 5/8" max stock removal at the deepest part of the profile.
It was almost like on the out feed end the molder would pick up that last 6 of unsupported material (once it was no longer held down by the infeed roller). We tried lifting heavily on the outfeed side which helped occasionally, oddly, endless board seemed to help a lot (which we try to do by default).
It was a brand new set of knives.
Just wondering if anyone has any input.
Had the same problem until i bought the
I put a dado head on the table saw, and power feed the stock through it to remove excess material. Do you have any tables or supports? Essential running long stock.
Make sure when you are feeding things through that you are always butting the next pc tight to the one that is finishing up in the molder.
I've made myself some infeed and outfeed tables that have helped greatly in the quality of the moldings.
I also made this gadget to lock down the open side of the molder to prevent chatter.
Look at where the arms that hold the rubber feeders stop against the stop pins, mark it with a pencil. Take them out and grind a slot big enough to allow the feeders to lower about 1/4'', you can now take 2-3 passes rather than one huge one. Guy at the W&H booth at a trade show 30 years ago showed me,works great.
Leo, I have seen your tip with blocking and clamping the cantilevered side of the molder and I have never tried it but I dont feel like we get much chatter but I am going to try it next round for sure.
Tim, I will have to look in there to see if I can understand what your saying. Will run out and give it a look today.
Tim, I think I see what your saying. Grinding the slot allows the rollers to drop down much farther. We dont have a ton of problems taking multiple passes most of the time. But Im going to give this some thought before I pull them out. I think I get what your saying. Makes sense.
The multi-pass kit (or modifying the machine to those specs yourself) will help but not completely solve the problem.
The multi-pass kit will let the feed rollers drop lower, better holding the wood down on the machine table. Longer, softer springs are then used to hold the rollers in that lowered position. This helps put more pressure on the wood.
However this is only part of the solution. On the outfeed side we will apply upward pressure on the board about 3' to 4' out from the machine, and then downward pressure with the other hand right up by the machine. This forces the end of the moulding down onto the table so it won't lift up into the knives.
On the infeed side we do the same thing but with the downward pressure hand further back for safety.
End snipe is nothing more than the ends of the board lifting off the table surface and raising up into the spinning knives. The above described hand pressure method will help to keep the ends of the board down. Some end snipe will still occasionally occur but this helps a lot.
I struggled with this for years and recently I started lifting up on the piece as it nears the end and it completely eliminates snipe.
The method BH is describing is used on any planer that doesn't have strong feed rollers.
Anyone that has used a shaper with a feeder deals with it in exactly the same way. Its a learned feeling in your hands.
I will second Adam's support of Bernie Davis's third paragraph - about support and counter support for things going into and out of planers.
This is fundamental.
Some of the old cast iron beasts needed no support in or out on the lumber it was planing, but most smaller shop planers still need help. I have an 18" P-Matic with adjustable feed rollers so it runs tight, but I still have the habit of bending the thinner stock on the way in and especially on the way out towards the end. No snipe whatever.
Yup, it's a tactic I use on the last pc of molding coming out of the W&H. Usually when they are run end to end you don't get snipe. Sometimes I use the test pc as the last board which helps eliminate the end snipe.
But it also matters on how much material you are removing. If you are taking a big cut then it's likely no matter what you do, you'll end up with some snipe.
Larger moldings are run in 2 passes (or more). That way you can just run a kiss cut on the final pass. But depending on the molding it might not work. I have moldings that are raised on one edge and very shallow on the other. The rollers won't bend that much to keep full contact on both sides. So you have to take a lighter 1st cut which retains contact for the second pass with both sides of the molding and the 2nd pass is where you take off to the final thickness.
We have always done the raising up on the outfeed side but I can see the advantage of the two hand approach applying down pressure close to the machine and bowing the piece up on the outbound hand.
Its odd that the endless board method helps so much even without raising the outfeed part.
On this last run we took to 3 passes, which sucks, leaving the last pass at just a crank or half crank down on the handle. Still gave some fits. We dont run a ton of hard Maple (thankfully) and have used most of these techniques over the years in some capacity and never had the issues with snipe we had on this job.
Working it all into the plan but Im still chalking a bit of it up to devil wood (even though I know there are much much worse species)
Hard maple molds beautifully! One pass, full depth. To limit snipe you can also make sure to feed the lumber in so any curve to it makes the ends go down rather than up. Doing 3 passes at the extremely slow feed rate of a W&H is really expensive! Job it out to a shop with a molder.