Is it possible to get zero snipe?

[Wood Monkey]

I've just taken delivery of my first ever thicknesser. A DW733.

I've spent a couple of hours playing around setting the in-feed and out-feed tables and I've not been able to eliminate snipe completely. In fact, I think it has remained completely the same regardless of my tinkerings. Here's procedure I've followed and some observations. Have I done it correctly?

1. The in/out-feed tables are actually very slightly lower than the main table (centre table) on the inboard ends. I'm assuming this is correct as they are identical both sides and perfectly level from edge to edge with the main table and the adjusting bolts only raise/lower the out board ends anyway.

2. I've adjusted each table and laid a straight edge right through then checked the clearance of on each outboard end and across the width of the main table and contact is being made at every point suggesting the tables are set correctly. Result is minor snipe about 2 inches in from each end of a 2ft test board.

3. I readjusted and recheck each table independently against the main table, then rechecked across all three tables as I did in no.2 above and everything seemed OK. Result is identical minor snipe and per no.2.

Am I simply expecting too much or should I be able to get rid of the snipe completely? It is very minor.

Other than this. I'm very impressed with the DW and the finish is excellent.

Regards, Jon

 

[Mr Ed]

I also have the 733 and would agree that the finish is excellent and the snipe is minimal, but is there.

I always bank on not using the end 100mm of a board when planing on this or my Scheppach as I don't think you can ever fully eradicate snipe. I find that care exercised with how the material is offered into the rollers can help, by keeping it completely level.

I think you're never going to get rid of it altogether so I just plan to take account of it in my material allowances.

Cheers, Ed

 

[promhandicam]

One way, if you have someone to help you is to feed the work in continuously - it is then like having one long board. You can't do this on your own but with two it does work.

Steve

 

[SVB]

This is a really timely post for me as I have just taken delivery of a EB 260 P/T as my first machine.

I must admit that I though the infeed should be a gnat's higher than the centre table so, if exaggerated, the workpiece is going 'downhill' as the first couple of inches are fed through.

Am I totally wrong? Maybe something to try, you can always go back to level if no better!

Best of luck!
Simon

 

[Doug B]

I to have the DeWalt, i find the only time i get snipe is if i don`t support the timber as it is exiting.
When supported though, i find, i don`t get any snipe.

 

[Woody Alan]

This is a really timely post for me as I have just taken delivery of a EB 260 P/T as my first machine.

I must admit that I though the infeed should be a gnat's higher than the centre table so, if exaggerated, the workpiece is going 'downhill' as the first couple of inches are fed through.

Am I totally wrong? Maybe something to try, you can always go back to level if no better!

Simon if I get your drift you are referring to the surfacing (top) of the machine, not the thicknessing. Although if that's true then you would be talking about it being fractionally lower not higher. Anyway, the point is that snipe is experienced on the thicknesser action. I had an EB260 and it did cause it. I think (I never bothered) it can be alleviated to a degree by building a false bed so as to extend the lower table for infeed and outfeed.

Alan

 

[Racers]

Hi,

Yes, with a hand plane :wink: :lol: :wink:

Pete

 

[devonwoody]

Planing is another skill to learn like using a bandsaw and it comes out right in the end.
Balance/pressure comes into both tools.

 

[Steve Maskery]

Prom, I have to disagree with you. Having a friend to help does work, but it's not because it's like having a continuous board, it's because they (or you) are supporting the board.

In order to deal with thicknessing snipe it is necessary to understand what is going on inside the machine.

There are three cylinders inside the machine. The centre one has knives on it and does the cutting, the others feed the timber into and out of the machine. As they are steel, they are a very fixed distance away from the bed. However, the machine has to be able to feed timber which varies in thickness. This is achieved by having the feed rollers SPRING LOADED, and this is the cause of snipe.

Because they are sprung, it is possible to force a board up off the bed and therefore closer to the knives. If both rollers are pushing down by the same amount, then we don't have a problem, the board stays nicely in contact with the bed.

However, at the end of the cut, the infeed roller stops pushing down, as only the cutter block and outfeed roller are in contact with the board. If the workpiece is longer than twice the length of the outfeed table, the centre of gravity of the board is off the end of the machine and starts to tip. This pushes the last end of the board up into the cutter, because the spring is not strong enough to hold it down.

Snipe.

If you thickness a very short board, say 300mm, I bet you don't get snipe. It's because the centre of gravity is still on the bed and the workpiece cannot tip.

To eliminate snipe completely, the board must be supported so that it cannot tip at all. Feeding in another right behind it does nothing to stop the first board from tipping. It your mate holding it up that solves the problem. Sorry Prom!

Cheers
Steve

 

[devonwoody]

Can we clear up whether we are thicknessing or planing?

(Thicknessing I always support the board coming out of the thicknesser so its end doesnt rise to the cutter.)

 

[Anonymous]

Yes

it is possible to get zero snipe. You need a resonable length infeed and outfeed table on your thicknesser and guide the wood in and out with a firm grip to stop it lifting. I posted a thread on a mod to my thicknesser that removed all snipe a few years ago and a quick forum search will bring it up with photos.

not had any snipe since.

 

[Doug B]

Can we clear up whether we are thicknessing or planing?

(Thicknessing I always support the board coming out of the thicknesser so its end doesnt rise to the cutter.)

The DW733 is a portable thicknesser, so the OP can only be about thicknessing.
I find it`s all about supporting the timber on exiting, as posted. But far more eloquently put by Mr Maskery

 

[devonwoody]

OK, but supporting the end has meant I never went to the extension posted by Tony, but I do remember it.

 

[PaulO]

I'm with Steve.

As well as the entry angle of the work piece you also have to consider the thickness of the piece. Thinner work can vibrate when only held by one roller. The only way to avoid / minimise this type of snipe is to get a thicknesser that includes spring loaded pressure bars. These are included on larger industrial machines, and some older machines (e.g. Wadkin). These are two solid spring loaded bars that sit very close to the cutter block and push down on the work to minimise vibration. Pages 108 and 116 of Alf Martensson's Woodworkers Bible shows a diagram, as well as a comprehensive trouble shooting section and explanation of how to use a planer and thicknesser.

 

[motownmartin]

Feeding in another right behind it does nothing to stop the first board from tipping. It your mate holding it up that solves the problem. Sorry Prom!

Cheers
Steve

I disagree, what you get is an indentation in the board when the feed roller stops feeding the board through, this is due to the outfeed roller not gripping the board as well as the infeed roller. there are numerous ways to improve this.
1) keep the table bed waxed
2) keep the outfeed roller clean
3) support the board and help the feed speed keep constant
4) feed in the next board directly behind the previous board

Sorry Steve

 

[Steve Maskery]

Well we'll just have to agree to disagree, Martin.

Good general pints about keeping rollers clean and beds waxed, though, I'm with you there.

S

 

[motownmartin]

Well we'll just have to agree to disagree, Martin.

Good general pints about keeping rollers clean and beds waxed, though, I'm with you there.

S

Agree Steve, I think we'll all learn something from this thread and other similar threads as long as people put bforward their ideas

 

[devonwoody]

I suppose if you have two boards of equal thickness you should be able to feed them in with a 6" overlap, it should prevent the first board sniping whatever else you do?

 

[Ironballs]

I tend to get little snipe when thicknessing, similar to Steve I try to ensure that when feeding in the piece I try to have it as level as possible and support it above and below. I think the support above is more important as when the piece engages the in feed roller it pulls in and kick up the tail of your piece, so you need to exert some downward pressure to counteract it.

On the outfeed it's been said already, it's all about support, once the piece is past the infeed roller then it's only being supported by the outfeed roller and whatever length of outfeed table you have, it it isn't long enough then gravity will pull the piece down and the end will go into your cutter block. So it slows your work rate down but I only feed in long longer piece at a time, as I go round the back and act as an outfeed table. I tend to get more snipe when planing, which is a whole other story.........

 

[ivan]

This may be one of those cases when everybody is right, although each discussing slightly different aspects. Certainly the work can exert leverage and unwantedly lift a feed roller if not supported. The work might also not be completely flat, and be feeding concave side up. The feed roller springs may need adjusting too.

There will always be some play in the elevating mechanism. Either the bed, or the head can rock a little when work held under only one feed roller (either bed or head moves up and down so there's some clearance there) I thought this was what feeding one-continuously-after-another was supposed to avoid, by keeping 2 rollers always loaded?