Planed panel thinner at edges

[john]

After gluing up panels 11 - 12" wide for parts of the doll crdales, I put them through the planer to get them to the required thickness. All six panels were OK down the middle, but about 1/32" thinner at the outside edges. The same thing happened with my previous wide panels. Also got more than the usual snipe on what I would call the left trailing edge.

This has me baffled. Fortunately this is not a major problem on this project.

The planer is a 12.5" Delta with a cutter lock that is supposed to reduce snipe.

Any comments or suggestions on maintenance would be welcome.

TIA

John

[dusty]

After gluing up panels 11 - 12" wide for parts of the doll crdales, I put them through the planer to get them to the required thickness. All six panels were OK down the middle, but about 1/32" thinner at the outside edges. The same thing happened with my previous wide panels. Also got more than the usual snipe on what I would call the left trailing edge.

This has me baffled. Fortunately this is not a major problem on this project.

The planer is a 12.5" Delta with a cutter lock that is supposed to reduce snipe.

Any comments or suggestions on maintenance would be welcome.

TIA

John
Having edges that are thinner than the center (after be surface planed) needs me to suspect the blades. I can envision nothing else that would cause this.

As far as the snipe - I can give no valid advise. I have the same unpredictable results. It seems that the snipe occurs when I can least afford it.

If I cut the boards long so that I can trim the snipe - it doesn't occur. If the boards are precut to the required length - snipe.:rolleyes:

[pennview]

You might get closer to the answer if you have a piece of wood that's flat and true, and then run it through the planer once. Then measure the wood. If the knives are bowed in the cutter head, you'd get what you are getting now. Or perhaps they were ground poorly. The other possibility I can think of is the knives are lower in the cutter head on one end than they are at the other end. And this should be evident after one pass, but after multiple passes, depending on how you flip the wood between passes, you might end up with what you have.

Regarding snipe, I've found that much of it is caused by a lack of table support, either on the infeed or outfeed side, or both. I don't think there is enough mass in these smaller planers to eliminate all of it.

[pennview]

After sending the last, I though that having each blade tilted in the opposite direction, could result in what you're getting.

[heathicus]

What about the blades being worn more in the center due to that being the most used section of the blades? Would running most pieces of wood down the middle result in uneven wear that would cause this?

[shipwright]

Snipe is caused by the relationship of table rollers to table; the higher the rollers the rougher material you can plane and the greater the opportunity for snipe. Reduce snipe by lifting gently on the end of the board as it enters and exits the cutting area. The snipe happens before the board reaches the support of the outfeed rollers and after it leaves the support of the infeed rollers. Adding the right amount of lift at the end of the board will reduce and with practice eliminate snipe. Run pieces too short for this fix on top of another board and there will be no snipe at all.

[charlese]

Hi John! I favor pennview's idea! One standard way to reduce snipe is to make sure to receive (slightly lift) the board as the back end is passing by the first roller.

[john]

Some food for thought in the comments I received. All-in-all, I think I need some serious maintenace on the planer, as well as the trusty old SS.

I do tend to flip the boards while planing so maybe the problem is on one side only but I am transferring it to the other side while flipping.

I try to even out the blade use by planing narrower boards at different points across the infeed table after I noticed a tendency to put them through at the right side (facing infeed).

I lift the boards as they come out of the outfeed side to prevent snipe. Seems to work on narrow boards but not on these wide panels.

When I finish this order for three cradles, (I don't like making multiples!) I will have to take the time to do some maintenance!

Thanks for the input.

John