Replies

1. 
   ring | Jun 24, 2008 07:11am | #1

   You need to identify the problem, and there are a few possibilities:

   1. Your frame stock is not planed square. If the edges are not exactly 90° to the faces, your clamp pressure to draw the joints tight will also create a winched frame.

   2. Your dowel holes are not perpendicular. Check your drill press setup (or however you're drilling). Again, if it's not perfect, the misalignment will multiply itself around the frame and cause it to go out of plane.

   3. Your cut-off of the rails is not dead-on 90°.

   4. Your clamping pressure extremely unbalanced. This option is unlikely, and last on the list.

   In general, I don't like dowels as a system for frame and panel doors, but whatever the system you choose the material preparation needs to be perfect. Check your steps systematically, and also consider using cope and stick cutters in the future.

   David Ring

   http://www.touchwood.co.il/?id=1&lang=e

2. 
   oldusty | Jun 24, 2008 07:24am | #2

    Russ,

                Every thing Ring said is true , I can add one important factor when clamping any door frame .

          Sight down the edges of the frame when you lean the clamped assembly against the wall or bench and tweak the bar clamps to correct the twist .

      Fyi , smallish doors like the ones you are making , even after making thousands of doors are imo the most difficult to keep flat , if that makes you feel any better .

               good  luck            dusty

1. 
   RussU | Jun 24, 2008 04:33pm | #3

   Thanks to both of you for the responses.  I did check my table saw for square and it was good.  I used a self centering doweling jig to drill the holes so I think that part should be accurate.  Thinking about what you wrote, it is probably uneven clamping pressure.  I used pony pipe clamps and there's a lot of play in the clamp faces.  I haven't invested in the expensive clamps where the clamp faces stay parallel but should probably do so.

   Russ

1. 
   saschafer | Jun 24, 2008 04:48pm | #5

   "I used a self centering doweling jig to drill the holes so I think that part should be accurate."

   Unless you have a magical doweling jig (that I've never seen before), at best the tolerances between the bushing and the drill bit are going to get you to within about ±2° of perpendicular. And a 2° discrepancy over 11" is 3/8".

   -Steve

    

3. 
   hammer1 | Jun 24, 2008 04:35pm | #4

   As others have said, your pieces have to have 90° ends and edges. It's very difficult to get the dowels perpendiculer when drilling by hand, even with a jig. When gluing up, clamp your doors down to a flat surface and use some wax paper under the joints so you don't glue the doors to your bench.

   Beat it to fit / Paint it to match

   
1. 
   oldusty | Jun 24, 2008 04:53pm | #6

   hammer,

                  Would you use that method on a large set of doors , I ask because it seems like much room would be needed , or do you do a few at a time ?

        And what about the squeeze out on the back side going into the wood ?

              dusty

1. 
   hammer1 | Jun 24, 2008 05:24pm | #7

   With good square joints, it's almost difficult to get a door to not be flat. If I feel there is a possibility, I clamp them down, big or small. I have five workbenches. I might have to clean them off, LOL, but I have plenty of space. By the time I get to the last one, the first is set up and can be removed from the clamps. I put wax paper under the joints for squeeze out but I'm pretty neat when it comes to glue. It saves a lot of time and headaches later.Beat it to fit / Paint it to match

1. 
   thumbnailed | Jun 24, 2008 10:25pm | #8

   I lay my doors out on horses while clamped, allowing easy cleaning of the backs ( usually scraping after glue tacks up, it avoids smearing glue into the grain ) and leaving my benches free, and use winding sticks to make sure they're flat. I'm pretty sure I've seen a competent description of how to use winding sticks in here. You also want to be carefull not to clamp too tight and glue-starve the joints, they should go together without too much force. 

2. 
   RussU | Jun 25, 2008 07:05am | #9

   Thanks for the picture.  I'm going to have to redo two of the doors so I'll give it a go with clamping them to the benchtop and see what happens.

   Thanks again to everybody for the suggestions.

   Regards,

   Russ

3. 
   chaim | Jun 25, 2008 05:37pm | #10

   Your picture depicts a good way of keeping a panel flat during glue up, but if it was off to start with it will probably just spring back when you release the clamps!

   that being said this is often the method I use too.

   ChaimMake your own mistakes not someone elses, this is a good way to be original !

4. 
   HowardAcheson | Jun 25, 2008 05:48pm | #11

   I have not seen what I find to be a key issue when making doors. That is to be sure to start with wood that is completely acclimated to your shop environment. I find that the number one reason for doors to warp is that the wood is still changing it's equilibrium moisture content.

   Of course, you saw must be properly set up to produce 90 degree rips and crosscuts.

   Be careful to evenly tighten your clamps and do not overtighten.

   Finally, you need to be careful that the doors are stored in a way that allows air to easily and completely circulate to all surfaces. Never lay doors down flat against another solid surface or another door.Howie.........

   
   

   ---

   Edited 6/25/2008 10:49 am ET by HowardAcheson

5. 
   gb93433 | Jun 25, 2008 09:06pm | #12

   When wood is glued together it should be in a stable state. Each piece of wood must be stable before it can be used to make a stable panel. While allowing the wood to stabilize I place the pieces on edge and covered so that any sun will not shine of them. By placing them on edge it allows air movement around the faces. If a piece of wood is laid flat in a shop the top and bottom of a piece of wood will experience different temperatures, different amount of sunlight, and differing air movement.