JJP12 - adjusting rollers?

[Michael Titus]

The troubleshooting section of my new JJP12-HH (gloat) manual suggests "Adjusting rollers to proper height" and "Adjusting feed roller tension" to help minimize snipe, but it doesn't say HOW to make these adjustments. I called the Jet (WMH Tool) technical support number, but they could only tell me which nuts to turn (part #74 on page 34). There is no technical data that would allow one to use a dial indicator to adjust the rollers. Does anyone have any ideas? So far all I can do is turn the nuts to see what happens -- I'd like something a little more scientific. Thanks!

[Matt Meiser]

Before messing with it, have you run anything through? Mine didn't need any adjustment out of the crate based on its performance.

[Michael Titus]

Yes, I've run several boards through. I'm getting a small amount of snipe at each end of the board, plus more tearout on reversing grain than I was hoping for. The snipe is about .0015" -- clearly visible but still a huge improvement over my old lunchbox planer. Some JJP12 reviewers were claiming zero snipe and tearout: just wishful thinking?

[Curt Harms]

I don't have anything to contribute but I will be watching this thread for any information. Like Matt, I figured anything I changed would make it worse instead of better but the planer feed is certainly "positive". The feed roll tension could probably be relaxed some without causing feed problems but I'm getting excellent results so I'm not gonna mess with it.

[david huffer]

I'm bumping this to see if you ever gained any insight into this issue. I have the JJP-12 and after *finally* adjusting the tables coplaner I am now turning to the feed roller tension. I must at times slightly push or pull pieces into or out of the planer because otherwise the outfeed rollers will spin on the board but the board won't move. this spinning leaves nasty black lines across the boards that are a pretty tough to remove.

I've cleaned the rubber rollers. i just think now they need to exert more downward pressure. The manual simply doesn't describe how to make these adjustments.

Please let me know if you have any insight.

[Matt Meiser]

Whenever mine would start doing this I would apply a heavy coat of paste wax to the table and it would be good for quite a while.

[Curt Harms]

I'm not near mine right now. I know the infeed roller pressure is adjusted by a hex 'plug' on top of the roller shaft. Tightening the 'plug' compresses the spring underneath it and exerts more pressure on the roller. I assume the outfeed roller is the same.

[John Coloccia]

re: snipe
It's most likely your technique, not anything to do with the rollers. When you feed the board, maintain a little upward pressure until it's started feeding a few inches. When you grab the board, maintain a little upward pressure until it's done cutting. Then your snipe will most likely magically disappear. I would leave the rollers alone unless you really really have a reason to mess with them because you could be venturing into very frustrating territory.

Try to remember where a lot of snipe come from. Until you're past the cutter head, you're only being held down by one set of rollers. This goes for feeding the board in and taking the board out. By maintaining upward pressure on the board, you're insuring that the board isn't sagging, lifting the other end (the one under the cutter) and giving you your snipe. Any planer will snipe anytime you have boards that are much longer than the infeed/outfeed tables, unless you control the boards...and then most any planer will give you snipe free performance.

The tearout is a result of straight blade and feeding in the wrong direction, or with figured wood. It's just something that happens sometimes. You can minimize it on smaller boards by putting the piece through at an angle.