Long Stiles for Raised Panel Doors - Problem?

[Dru Dron]

Hello All,

I've got a lumber milling question for you related to some large raised panel doors I'm building out of cherry for a floor to ceiling kitchen pantry. I don't have much experience with raised panel doors yet (still fairly new to serious DIY woodworking in general) so I'm hoping someone more experienced can share some advice.

Two of the doors will be just over 65" tall so I have four stiles that length to mill that will be 2 1/4" wide and 3/4" thick. The problem I'm having is that when I try to bring these rather long, narrow boards down to final thickness I can't seem to flatten them on my jointer. After rough milling to about 1" thick I've left them stickered for several weeks to stabilize/acclimate and they tend to warp about 1/16" to maybe 3/32" which is probably to be expected. However, when I try to re-flatten these boards on my jointer they seem to be so flexible that I just end up with the same curve/warp to them when I'm done because I'm guessing the hand pressure required to pass them over the jointer seems to flatten them out (along the lines of what happens if you pass a warped board through a planer without flattening one side first on a jointer). I've tried using less hand pressure and I've tried cutting just the first quarter of the board length from each end prior to a full length pass and neither of these ideas seems to help. If anything, the boards become less flat (due to further stress relief on the first side I assume).

So I guess my main questions are:

1. Is there a reliable way/technique of solving these milling difficulties? Do I need to modify my technique with long, narrow and thin boards like these? By the way, I'm using a long bed 6" jointer from General International. It's not the greatest jointer out there, but I'm convinced I've got it tuned reasonably well since shorter boards (say up to 36" to 48") come out nice and flat. It's only these extra long boards that give me a significant problem.

2. If not, for large, raised panel doors like this do I even need to worry about the stiles warping 1/16" to 3/32" over 65" if the central raised panels stay flat (which they currently are and will hopefully stay). Each door had two panels roughly 30" long with a mid rail dividing the door into an upper and lower half. The stiles seem quite flexible at this length so I'm hoping the panels would be stiff enough to keep the overall door reasonably flat over time. Is this wishful thinking on my part?

Does anyone reading this have any suggestions how I could improve the results I'm getting with long work pieces like these? Am I worrying unnecessarily about this noticeable but hopefully minor warping (i.e. 1/16" to less than 1/8" over 65")? Will straight panels hold the long stiles straight over time without the overall door becoming warped or twisted in the long term?

Any advice or suggestions any of you might be able to offer would be greatly appreciated.

Thanks,

Dru Dron
Guelph, Ontario, Canada

[Peter Quinn]

Hi Dru,

I should start by saying I don't like doors that tall that are so thin. But frankly in practice the hinges will hold the door fairly straight if the cases are rigid. Do not count on the panels holding the door frames straight in most cases, though it could happen. 1/16" bow may not mean much over almost 6 feet, depends on the design and the reveals.

I have that same jointer in my shop, though I have since added an 8" and haven't used it in several years regularly, its a good solid machine in that weight class. Six feet is at the upper end of its capacity to flatten as you have noticed. It is critical that your pressure be applied sideways against the fence as you advance the stock and not down against the table. You can easily press the boards against the table with stock that thin rather than actually flatten the boards. Its also critical that you keep all your fingers, so be careful where you put them as you concentrate on flattening. I can't use enough words to describe a procedure that is largely a mater of feel, but I can say that what you are trying to do on that machine is not easy, so keep at it. It will take nearly perfect technique, which takes time, so practice on something cheap like 2X4's or scrap, and take light passes. Remember to push forward without pushing down, and that a push block with a hook at the end can help save your fingers and your stock.

[Eiji Fuller]

Straightening long and thin boards is sometimes difficult.

I extend the outfeed table to support the entire length. super sharp knives are a must.

when flattening a long thin board I only put pressure on each end of the board and never press down on the middle part of the board. Obviously that cut can only be accomplished accurately if the cutting action doesnt lift up the board. That is why the sharp knives are a must.

Another easy way would be to dimension them 1/16 to 1/8 oversized
let them be on stickers. Then flaten one side with a hand plane and then thickness it in the planer.

[Chip Lindley]

Often times, if only one side of a board is planed or jointed, some bow will result, because of unequal stresses and moisture content. Allow the board to rest and see if it warps upward off of a flat surface. If so, flip it and let it rest on the opposite side for a day. The board(s) will finally equalize. Some wood without very straight grain has stresses built into it. Try to find the straightest grain boards for your stiles, and your chances of success will improve.

As Peter stated, 1/16" bow over 6 ft. is not much in a 3/4" thick board. The hinges (at least 3-probably 4) on a door that size will hold one side flat. If two doors will close together, covering one opening, your hardest job will be to find two boards with the same amount of bow. Hint: flatten one 5" board and rip it in two for matching stiles. If the bow is equal in both doors, it will not be decernable to anybody but you. That is something you can live with.

[Joe Chritz]

Make sure you only use pressure on the outfeed table after the board is engaged on the cutter head.

Long pieces are especially picky so I am really careful to pick the best stock for those. As close to 1/4 sawn as possible.

That amount of warp should be taken care of by the hinges but you never know for sure until you get them mounted.

Joe

[Alan Bienlein]

Dru how straight were your boards to begin with? I just did a 60" plus pantry door for our kitchen pantry and got mine straight using a 6" ridgid jointer. If the board is bowed you just can't set it on the jointer and run it thru if it's not fully supported by the bed. Mine had a 3/16" bow and what I did was move my gaurd and started jointing in the middle of the board, turned it end for end and did the same thing. I would turn the board on edge and sight down it and once it looked straight I would do a full pass on the jointer. Then I would run it thru the surface planer to flatten the other side but not to final thickness. I would sticker my pieces for a day or two to make sure they didn't move on me any more and finish them to final thickness. It's all about technique and understanding what you need to do to the board to get it to do what you want.

[lowell holmes]

I'm not advocating this in your case. . .

Thirty years ago, before I knew better, I had a boardroom door to build. It was to be a 60" wide x 84" tall door made with 8/4 walnut and a bronze glass panel.

I ordered the wood s4s and they came in perfect except for bow in the length of them. There were two bowed pieces. I didn't know what to do (I would straighten with a hand plane now), so I ended up ripping the bowed pieces into two equal width bowed pieces each. I had four 7' long pieces that were bowed.

I clamped the bowed pieces together with the bows together straightening the pieces. The bowed pieces clamped together were from the same board in each case. While clamped toether, I marked dowel positions on 6" centers and drilled dowel holes. After doweling the the bowed pieces together with the bows opposing each other, the result was straight boards. The gluejoints were not visible because the grain matched, the pieces being from the same board. THe door lasted for years.

This is a true account of an improbable soution to a problem. I was lucky.

Today, I would not risk this. but would order over thickness and straighten with a hand plane.

[Ralph Barhorst]

What Joe said; use 1/4 sawn or straight grained wood to reduce the problem

[David Giles]

Wouldn't worry about it. Many a cabinet shop makes doors, drawers and boxes without a jointer onsite. Buy reasonably straight wood, saw it oversized, set for a day, then saw to final width. 3/4" thickness can easily be straightened with only hand pressure during assembly or glue ups. You know this is true because it easily deforms to hand pressure when you try and joint it. The stiles will conform to the center raised panel. If the RP is flat, you're good.