Wood getting stuck in planer

Some possible causes and solutions to the problem of wet wood getting stuck in a planer. June 14, 2000

We mill white cedar, some cypress and some Doug fir. Most of our material is air-dried, although there is often some surface moisture on the wood.

We purchased a Pinheiro 600/5 planer/moulder last year, and have been mostly pleased with its performance, except when we try to run wood that has some surface moisture. Whatever the species, we have the problem of wood getting stuck in the machine whenever it hits a wet spot. Has anyone else had this problem? What did you do to solve it?

Obviously, the best solution is to mill completely dry lumber, but that is not always possible for us as we have outside storage (tarps trap a small amount of water). When the problem occurs, the feed roller continues to turn, and the wood gets shredded; we have "aggressive" feed rollers installed. They are sharp and I'm wondering if we should consider putting blunt feed ones on, to increase the surface area. Any suggestions would be appreciated.

Forum Responses
Wet wood is a problem for many operations. Several things can be done to reduce the feed problem.

The first thing I'd do is use a high-quality table lubricant such as Wax-A-Glide. This lube reduces the friction between the wood and the table of the machine.

Another thing that needs to be addressed is machine alignment. Is the fence straight and square to the machine frame? If not, then the wood is losing control, and this causes jamming.

Are all the knives sharp? A dull tool cannot properly pull wood through.

As for the feed rollers, I suggest using the least aggressive roller for the application. In most wood applications, I use urethane rollers. I suggest either an 80 or 90 duro, or hardness, roller. They're available from Western Roller Corp., or Axiom Industries. Many distributors offer them as well.

As a note, many of the companies that are discussed in this forum offer discounts to members of several of the educational associations. If the manufacturer does not, some distributors do.
Dave Rankin, forum moderator

Thanks for your response Dave, I'll try the table lubricant to see if that helps. We've experimented with the fences and I do not think there is any excess friction - they are well aligned.

As for the rollers, why do you suggest the least aggressive rollers for the application? Is it because if the rollers are too aggressive they may have a tendency to tear right through the wood?

If that's so, I think that IS indeed the root of our problem. Are there any simple procedures I can do to check and see if the rollers are the problem? I'd rather not change the rollers unless I'm pretty sure that is what the problem is.

If the feed roller is too aggressive, especially in wetter wood, the rollers will dig into the wood and create a divot. This causes the wood to stall. By using a urethane type roller, for example, the roller will not dig but can slip a little. By cleaning the urethane roller with quick-drying lacquer thinner or alcohol, the pores of the roller are opened, allowing for better gripping. On a metal roller, if it is dull it will simply not feed well.

The diameter of the roller is also critical. All rollers must be the same diameter.


The comments below were added after this Forum discussion was archived as a Knowledge Base article (add your comment).

Comment from contributor A:
I recently purchased a Makita 2120b 12 inch planer. Works great, however I find that a good spray of CRC Dri Lube (teflon spray) on the tabletop makes the timber run through much smoother. Remember to let the spray dry overnight.

Comment from contributor B:
There are many things that can cause wet wood stalling. Bottom rollers collect wood bits that may not cause a problem until wet wood comes through. The slight resistance at the bottom rollers can be magnified when wet wood comes through. Keep these bottom rollers free of wood chips.

The wet wood is softer and likely to require more infeed/outfeed roller pressure to keep the stock moving. Try thinner material removal settings. This may require several passes, but at least you would not get shut down.

Adjust the pressure on your infeed and outfeed rollers. The best time to adjust them is when new blades are installed. Run through a previously planed board and observe for any twisting (the board coming out at a different angle than entered). This will indicate uneven roller pressure. Adjust the roller pressre one side at a time with this same piece of stock for a straight pass through.

There should be a left side and right side feed pressure adjustment. The same for outfeed. You don't want to see a piece of wood turning left or right. (If there is a knot or wood density changes, this turning condition is normal.)