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First Project snafu.. please advise

3K views 50 replies 22 participants last post by  renners 
#1 · (Edited by Moderator)
I am a novice who has been following this site for quite sometime. I finally signed up since I needed to ask all you experts a question which is causing much tension at home…

I decided to take the plunge a year ago bought a few basic machines from Grizzly, an HF dust collector, some pipe clamps on craigslist some 4/4 Ash lumber from CR Mutterspaw & started making some sawdust. The goal was a interior (hanging) sliding door (which my wife rough sketched see attached jpg)
Rectangle Parallel Font Slope Engineering


The door dims are 48" wide x 83" tall x 1.5" thick (including frame thickness)

Following the advice on this site, I let the lumber adjust to my garage, jointed and planed it and let is sit some more. Then planed it to final dims.

I built the door frame (see attached door.jpg rear side) using mortise & tenon joinery for all joints… it was quite an experience. Checked for squareness and did the glue-up

Then I did an edge to edge glue-up of all the panels and joined it to the frame using #10 screws, countersunk them. I learned about cauls too late & had to touch up a few misaligned glue joints with a low angle block plane & a brand new handheld orbital sander … as you can imagine the $$ are adding up and still no door :).. but who is questioning anyway

Finally door was completed, i primed & painted it (ours is not to question why..) per request. The inlay panel which you can see in the pictures were stained and finished with some Varathane protectant.
Wood Rectangle Orange Floor Shade


Shelf Rectangle Wood Shelving Table


The door was heavy (of course) but in decent shape. I attached the hardware and hung it. Within a couple of days the door has bowed making it a sore topic….There cannot be that much difference since this was assembled in our 2-car attached garage. Please see picture.
Wood Ceiling Tints and shades Glass Metal


What can I do to salvage this? Can it be salvaged? What did I do to screw this up? Any advice would be huge
thanks all
 

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#2 ·
I'd do one of two things…

Either bolt some angle iron down the length of the sides, painted white to match the door. Or, I would rip a groove in the sides (edges) and put in a metal truss (square bar). You can get either from a big box store.

If you choose angle iron, you could remove material to make the angle iron sit flush with the wood.

I cannot think of a solution without using metal at this point unless you are willing to really plane down the thickness of the door itself. That would relax the wood and perhaps solve the problem. Aluminum is an option if weight is a concern.

And, yes, there could be a huge difference in your shop environment and your home. That appears rather obvious right now.
 
#3 ·
Not that this helps a lot, but I am having a miserable time building a table out of Ash. No matter what I do, this wood does not want to stay square.

With pieces THAT big, I would think warping is unavoidable. Since it's painted, I probably would have saved the ash and used MDF or baltic birch plywood. I've never made a door (or anything that large) though. I can say that I have never seen an 83" piece of solid lumber remain perfectly straight/flat.
 
#4 ·
BTW, you might just try pulling it down and clamping it up along its length for a while. I doubt it will remove the entire bow because of spring back, but it'll help…especially since you'll. have to do that to apply other solutions.

Another option is to run some eyelets in the top and bottom and cable it up with some tout airplane cable. Thus would pull door back into shape and allow you to actually hyperextend past the bow. Think of it like braces for your teeth.

Just some additional brainstorming there.
 
#7 ·
How much trouble would it be to separate the frame from the panel? I might try pulling them apart, force the panel flat (maybe a slight bow in the opposite direction) and re-attach the frame. Another coat of paint on the frame side of the door might also help a bit.

The width of the framing is very small for such a large piece.
 
#10 ·
Cosmic's solution is the only way, I have used the iron square trick to straighten beams.

I think the question you should ask yourself is why did it bow? Now you know your construction method was not appropriate. If I am seeing your diagram correctly, you screwed the front part to the frame, a 1.5" frame this long is not stiff enough to prevent the wood from moving, which is what happened to the front.
 
#11 ·
Good idea, Jonathan.

@Indianwoodchipper - If look at a bookshelf, there's normally a face board attached to the shelve edge. The principle is to prevent the shelf from bowing under weight of the books. For tables, the apron serves the same purpose. Jonathan is advocating the same type of thing, and it adds a functional element at the same time. The maple is a heavy, stiff wood that would help bind the door in place once you have the ash straightened. The only real question is whether or not it will be enough to hold it? I would suggest that the maple needs a bit more mass than Jonathan has drawn, but the principle is solid. You could even figure a way to sandwich such a board to a piece of metal plate between the maple and the existing door. Or, for that matter, just use the plate itself.
 
#12 ·
Hmmmm…

I wonder where the bow is coming from? It seems that the panels are a series of shorter Ash boards, edge glued to make a panel. I don't see why those would bow. So that might indicate that the frame is the issue. So, as GregD asked, can you separate the panel from the frame? If they are just screwed to the frame and not glued, this should be doable.

What I hope you'll find is that the panels are far less bowed than the frame - because the frame is what was pulling them into a bow. You might still have to flatten the panels by laying them flat and piling lots of weight on them for a couple weeks (IN the house), but you may find that they are still quite usable.

Which would mean you just have to replace the frame. Since its painted, MDF or birch plywood might be a good choice.

For the future (as several have pointed out), three things to watch out for are:

1. Garage is not house. Acclimate lumber to the target environment.

2. Man-made materials are more stable. For painted pieces, use man-made where practical.

3. I, too, find that Ash is unstable, especially long pieces. The greater the length, the more stable material I want to use.
 
#15 ·
I think you have some good ideas here for a fix, but I can add some insight as to why this may have happened. Most of the boards on the door are running horizontally, with the frame boards running vertically (aka perpendicular to each other). I'm sure you've read about the difference in wood shrinkage/expansion across the grain compared to with the grain.

It looks to me like the humidity was higher in the house, causing the boards to swell. When this happens there is more expansion across the width of the boards than along their length. So the horizontal boards of the front swelled more in the vertical direction than the frame boards did, causing the bow.

I hope this isn't too confusing!
 
#17 · (Edited by Moderator)
What was the moisture content in your lumber when you started? What is the temp difference between the 2 rooms your using this for? When you edged glued did you alternate the grain pattern? Looks like every board bowed perfectly with each other. Makes me think the temp and humidity between the 2 areas is severe.

my opinion on exterior doors it is best to use laminated material and veneer the outside.

Sometimes things like this just happens and you learn from them and move on and start over. Overall you did a fine job, If you want it to not be a topic for all time start over and use some laminated material in between and use 1/8 or even 1/4 thick veneer on the outside. Be nice to know what you do and how it turns out… A lot of advise was given and i am sure everyone would like to see the final outcome… Good Luck…..
 
#18 ·
IMHO, Rex Bair is spot on as to why this happened.

When dealing with wood or other natural products, it is important to create balanced panels. Meaning, the front and back need to have equal expansion and contraction rates. This is not the case in your door- It is an unbalanced panel.

With moisture and temperature changes, wood expands and contracts greater in width than it does in length. Even with perfectly straight boards and all the angle iron in the world, an unbalanced panel will tend to bow as yours did.

The nice thing about engineered panels, (plywood, mdf, pb.) is that they are dimensionally stable. The width and length expand and contract at equal rates. This is why such materials are preferred in large doors such at yours.

Chalk it up to a learning experience and use this experience to make a better one next time.
Best of luck to you.
 
#19 ·
By way of clarification, you don't have to build a door like this with engineered lumber. (Plywood, MDF, or PB)

You can build this with solid wood as long as you allow for the expansion of the respective materials. e.g. Frame and panel door construction allows the panels to float in the frame so the expansion of the panel does not affect the overall door.

Similar considerations can be made in re-designing your door to get the desired look without the expansion issue causing your door to bow.
 
#21 ·
my take is the paint

the cross boards are painted on one side
and raw on the back
the paint has brought moisture to one side
making them swell on that side
(like a dry sponge on a wet counter
it gets bigger around the dry side)

just a thought

hope you resolve soon
it is a nice door
 
#22 ·
If I'm correct, taking it to the same humidity as when it was assembled would make the bow go away. Taking it to an environment with even lower humidity would actually cause it to bow in the opposite direction. This could even happen with seasonal changes over the course of the year if the door was left where it is.
 
#23 ·
Wow! Thanks for the support guys this is quite an education. This forum rocks so do all of you…

I will try and answer all the points/questions raised so far and apologize if I missed your question

• This is an interior door to my son's - to be new room. No excessive water or moisture on one side only. BTW the panel side is bowing outwards and the frame side has "shrunk"
• I am disappointed with myself since I thought the paint job would "seal" the moisture IN or OUT and not have to worry about this
• Thanks for the explanation regarding expansion along the width of the board vs the length on the frame
• Also I do see your point on perhaps needing a beefier frame
• Both sides are painted & so are the edges
• I also did alternate the grains on most of the panels since I thought this would help.. not all the panels though. Could that be adding to this?
• I do not have a moisture meter & did not measure anything before or after
• I did consider ¾ Baltic birch for the door & only make the inlay panel out of Ash BUT I read in one of these forum that plywood of this dimension, left free hanging would become a 'potato chip' in no time

NEXT STEPS-Solution/Question
• I am leaning towards, letting it lay flat in the house with weights. Maybe attaching angle irons & painting over.
• Would you guys recommend putting the iron on the frame side or on the side of the panels which are bowing out
• Instead of an angle .. Should I use flat bar-stock on both sides - use my router to make a groove to recess the bars & put a few bolts through both bars. Make a bar stock sandwich. This might also go with the look of the hardware if I painted the bar stock black?
• Would Aluminum bar stock do the trick? Trying to keep the weight down

thanks again for the support and encouragement to the new guy
 
#24 · (Edited by Moderator)
We recently took in a table top made from 6/4 solid oak planks. It was 36" wide X 48" long.

The layup was perfect - the grain was alternated every 4 inches or so. Everything was fine, except…
They had only finished the top and edges-The underside was left RAW.

With time, moisture escaped from the raw side and it shrank relative to the front. (This is in Arizona where the outside air is typically dryer than the wood moisture content. Your neighborhood may have the opposite issue.) The result was a 1" bow over the length of the top.

We had to re-cut and re-alternate the planks so that, as the moisture stabilized, the new expansion would cancel out over time and the top would remain relatively flat. We finished both sides for them as well.
 
#25 ·
The only problem I see with bar stock or angle iron is that they are trying to fix a cyclic problem. That bow will come and go with the seasons, and it may even bow the other direction. On the other hand, you have a lot of experienced woodworkers backing up those solutions, so I may be completely wrong to doubt them.

If you do try using angle iron or bar stock, go fairly beefy and use a lot of thru-bolts. In this respect I like your "bar stock sandwich" idea. IMO using aluminum would not be a good idea. Make your bolt holes tight and crank down on those bolts. Maybe even use spring washers to avoid the bolts loosening if the wood shrinks a bit in thickness.

I've got some experience engineering composite materials, and wood behaves very much like a composite.
 
#26 ·
@Indianwoodchipper - Be careful with one assumption. Sealing something with paint or finish might keep liquid moisture out, but not water vapor (which is what humidity is). Some finishes are more impermeable than others, such as shellac, but just about anything can be warped by humidity if severe enough. Latex house paint does almost nothing to stop humidity, even though it is very impermeable to water. In other words, the boards on your house can still swell due to humidity, but still wick away destructive water.
 
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