Jet Jointer/Planer chip-dust problem

[Curt Harms]

I've had some more time with my January acquisition (life get in the way) and have an issue that I haven't yet gotten a good answer to. When in planer mode the dust collection sometimes doesn't work well at all. I did some investigating and discovered the door in the dust collection hood "flies" i.e. lifts up from its correct position in the airstream. I discovered 2 sets of 1/4" holes in the sides of the hood. They happen to hold this flap in either the jointer or planer position. There's not a problem with the door in jointer position, it fits flat against the hood and no air can flow on top of it to lift it. In planer position there's about a 3/8" gap between the flap and the top of the dust hood. It appears that air flowing thru this gap lifts the flap and impairs the dust collection. When I put a dowel thru one set of the above mentioned holes, the dowel holds the flap in position and dust collection is fine.

I emailed Jet and their thought was that I have "too much dust collecton". I didn't know there was such a thing. I did experiment this morning with opening the blast gate only part way. The dust collection seems to work fine with the blast gate only open about 1/3 of the way. This still seems to be ...uh..."suboptimal" even though it worked fine. I then opened the blast gate all the way and removed the dowel holding the flap in planer position. I ran a 5"wide piece thru the planer and the dust collection was STILL fine even with the flap free to lift and the blast gate wide open. I'm gonna have to play with this more but it sure is hard on my scrap lumber supply, it all winds up in the D.C. bag. I'll keep everyone apprised about how this plays out.

Curt

[Don Abele]

Curt, IIRC correctly there was a post somewhere about that door sticking. I did a quick search and couldn't find it though.

That answer for Jet seems like BS - too much suction, yeah right. Their info page lists a minimum of 400 cfm. Maybe they need to add a MAXIMUM rating as well.

I'd give them a call and not hang up until I got an acceptable answer: 1-800-274-6848.

Please let us know...I'm currently in a holding pattern on my purchase and this will definitely factor in to my decision.

Be well,

Doc

BTW - can you shoot some pics to show what you are talking about?

[Steven DeMars]

Not sure how it is constructed, but is there any way you could add a piece of rubber like a door sweep, or in a gasket mode? How about a small piece of steel plate to serve as a counter weight? A well placed spring?The reason for my curiosity, I had planned on purchasing a stand alone planer and jointer. After reading several post on the forum, your included . . . I have redirected my attention to the JET Planer/Jointer.

[Curt Harms]

Not sure how it is constructed, but is there any way you could add a piece of rubber like a door sweep, or in a gasket mode? How about a small piece of steel plate to serve as a counter weight? A well placed spring?The reason for my curiosity, I had planned on purchasing a stand alone planer and jointer. After reading several post on the forum, your included . . . I have redirected my attention to the JET Planer/Jointer.

The thing almost behaves like a Kreuger(sp?) flap. It appears that air flowing over the top of the door or flap through a slot generates lift. I'm skeptical that a spring or counterweight would work because the door does need to move freely. It needs a spoiler on top;).

Curt

[Curt Harms]

I took some pics and emailed them to Jet. I received a very prompt reply. They looked at and tried a machine on their floor. They feel the slot above the flap is too wide on my dust hood and are sending me another one. I think they may be right and I thought about a large hammer and block of wood but not on a new machine:rolleyes:. There doesn't seem to be a lot of familiarity with this machine yet at Jet technical support but they were prompt in their response. I'll keep everyone updated.

Curt

[Don Abele]

Curt, that type of response from customer service is reassuring. Please let us know if the new hood fixes it. I'm hoping to hear back from Byrd soon concerning the shelix head retrofit, as well as from Jet themselves when they get a roll-out date for the JJP-12HH with the helical head.

Be well,

Doc

[Curt Harms]

I received the new hood today. It isn't significantly different than the original one, there is still a gap between the door or flap and top of the hood though less of one. The only difference I noticed is that the new hood is flat side to side where it transitions to the round hose attachment. The original dust hood had about a 3/16" hump. When I got it installed I tried a narrow piece(scrap of 2 X 3) and a piece about 7" wide. The chip collection on both pieces was as expected. I won't have a chance to use it much til next week but the initial run is promising. I'll let everyone know if any other problems appear.

Curt

[Curt Harms]

I received the new hood today. It isn't significantly different than the original one, there is still a gap between the door or flap and top of the hood though less of one. The only difference I noticed is that the new hood is flat side to side where it transitions to the round hose attachment. The original dust hood had about a 3/16" hump. When I got it installed I tried a narrow piece(scrap of 2 X 3) and a piece about 7" wide. The chip collection on both pieces was as expected. I won't have a chance to use it much til next week but the initial run is promising. I'll let everyone know if any other problems appear.

Curt

Well the problem reappeared. Here's my solution as related to Jet technical support:
I found something interesting while switching modes. The first operation I did was face and edge jointing. Dust/chip collection was flawless and always has been. I switched the dust hood over without shutting the vacuum off, cranked the planer table up, engaged the feed rolls and fed the piece. Chip collection was back to spitting chips!!What?? It turns out that if I didn't remove suction while flipping the hood over, the flipper door would not drop, it stayed in the jointer position. I found that if I reached up and moved the the door down, it stayed down most of the way and dust collection in planer was fine. I also found that if I removed suction while shifting the hood from jointing to planing, the door moved down like it's intended to and when I reapplied vacuum the door lifted up a little but it worked fine. The upshot: don't move the hood from jointer mode to planer mode with vacuum on the hood. Pretty simple solution. The door flips properly with light vacuum but not with proper airflow.