MikeG.
Established Member
That would work":3v1hx770 said:
Those slots would have to be vertical, which means there is absolutely nothing preventing this "door" racking horribly.
Using Floorboards for Woodworking.
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Those slots would have to be vertical, which means there is absolutely nothing preventing this "door" racking horribly.
That would work
Established Member
Ye would certainly need some bracing
Why not make some nice breadboards instead?
Why not make some nice breadboards instead?
MikeG.":19d7j64l said:
=D> bingo!!!! that's exactly what it is. And why the word door in quotes? :lol: lol
Anyway, looks like im going to have to make a frame, will glue up a panel and reduce thickness to 10mm or so. That should be alright, right?????
p.s. no one yet explained why that last picture of the wardrobe has boards glued horizontally for a door and it seems to be ok.
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MikeG.
Established Member
Osvaldd":3wf10aqw said:
Because it will only look like a door for about 5 minutes. Then it will start falling apart.
I'd say that it was highly unlikely to be made of wood. That is, in all probability, going to be a veneered sheet of MDF.
Trevanion
Greatest Of All Time
Osvaldd":33fz217r said:
Notice the big bracings on the back of the doors to keep them from twisting and cupping? If they weren't there the doors would look more akin to sine waves rather than doors because they'll all move quite drastically, especially in a house with a bit of heat in the winter
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MikeG.
Established Member
There's a really good reason that doors are made the way they are made. Other ways are possible, as this example shows, but they will have a much higher failure rate. Unless I had perfect timber there is no way I'd attempt a door like that (think of getting all that end-grain perfect, for a start). You don't know much about your timber, and if one, just one, of your board decides to warp, the whole door will be twisted. I'll bet you could make this door ten times and a couple would work out sort-of OK, at most. Get some experience with ordinary doors first, Osvaldd, before you have a go at something like this.
Ttrees
Iroko loco!
It nearly looks like Chinese joinery like in this video
[youtube]aD6qdJNU7GE[/youtube]
[youtube]aD6qdJNU7GE[/youtube]
profchris
Established Member
Osvaldd":1dfdwe5j said:
It's doable, but ....
At 10mm I'd expect each board to cup along its length in different directions and in different amounts, depending on the grain orientation. The only way a door like that would stay flat is either (a) it's in a humidity-controlled environment which happens to match the humidity when it was glued up, or (b) all the boards have vertical grain (and even then there are no guarantees about movement). OTOH, if you want a washboard effect after a few months, then this is the design to go for!
Just to give you some idea how difficult movement from humidity can be, I make musical instruments with tops only a little thicker than 1.5 mm. A humidity change can swing them from convex to concave, even if I have glued 8mm spruce braces to the backs!
profchris
Established Member
Osvaldd":pkbdukrj said:
Maybe, but it's rather a gamble.
If I were trying I'd take one board, plane it down to about 6mm (if that's what would work with a frame) and then observe it for a week or two.
Does it cup, does it twist?
If it does, can I cope with the result or counteract it with the frame/braces?
I'd guess the answers might be Yes and No, but you might be lucky
The consensus of the experience that you've been offered is that the resulting product will be very unsatisfactory in the medium term, probably on a time scale of months. This is because the design conflicts with the dimensional changes of wood as the external humidity changes. A good design will respect these changes: almost zero along the grain (usually much less than 1%), several percent in radial directions of the original log, and more still (10-15%) in the tangential directions. (Get 'Cut and Dried' by Richard Jones of this forum to learn more. MUCH more.) Since a floorboard will have a mixture of radial and tangential grain across its width, the effect is of cupping on drying. This is combatted in floorboards by nailing them down at every joist or glueing them to a substrate but you can usually still see it on most floors. It is combatted in doors by making the dimensioned part (the frame) out of long grain pieces, and by fitting the panels in slots that allow for changes.
But you don't have to believe us. You will learn much better by making the piece and studying its behaviour. If the boards have been stabilised by long domestic use in a dry house, and not exposed to a humid workshop for more than a few days, the cross-grain shrinkage would be much less than in new timber. Nothing is so educational as a mistake.
But you don't have to believe us. You will learn much better by making the piece and studying its behaviour. If the boards have been stabilised by long domestic use in a dry house, and not exposed to a humid workshop for more than a few days, the cross-grain shrinkage would be much less than in new timber. Nothing is so educational as a mistake.
I'm more confused than ever. So in addition to it being a poor design the boards themselves are somehow bad? Because they are not cut right? Not enough straight grain or something?
If the boards are not the problem, other than being too short, please help me with the design(or just tell me to forget about it). Most of the boards are short-medium length. I can get some longer ones for frames etc..
So knowing that, can come up with something like in the pictures below.
If the boards are not the problem, other than being too short, please help me with the design(or just tell me to forget about it). Most of the boards are short-medium length. I can get some longer ones for frames etc..
So knowing that, can come up with something like in the pictures below.
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profchris
Established Member
Osvaldd, your first picture might work, your second one almost certainly wouldn't. To make a design, you need to understand why, so apologies for the lecturing tone (professional hazard ).
1. All wood moves around as the humidity in the air changes, and it always changes except in an expensively climate-controlled building like a museum.
2. Along the direction of the grain it hardly moves at all.
3. Across the grain it can move quite a lot. If, when you look at the end of a board, the grain looks like this - ||||||||||||| - then that will expand and contract the least. This is vertical grain. The more those grain lines seen from the end move towards the horizontal, the more the board will move widthways.
4. If the end grain is curved, then each part of it will expand different amounts. With more humidity it will tend to cup towards the inside of the curve, and as humidity reduces it will flatten out again. It will also expand and contract widthways of course.
5. Different wood species do this more or less. Mahogany is pretty stable (though it still moves), while oak moves much more.
So, applying these to your top design, you can see where the expansion and contraction will take place. You have to allow for that. What you have there is effectively a frame with two panels let into it (each panel made of three boards. That panel will get wider and thinner as humidity increases and decreases, and if it is all glued together this will push the frame apart, or pull it in and cause cracks in the panel. So your panel needs to float in a groove in the frame, which has enough space to allow for the movement. I'd guess that if you edge joint the three boards to make a panel, the whole thing might move as much as 5 or 6 mm, maybe even a little more.
The other thing to consider for this design is the end grain on the panels. If they are all going to cup, then you can reduce the overall effect by alternating the cup direction. If all your board will cup in the same direction, the cumulative effect will be huge! Ideally, you would select the boards for these panels so that they will cup the least possible amount.
Looking at your second design, the panel of three boards set vertically will expand in a different direction from the three set horizontally. Together, they will try to expand your door both widthways and lengthways, and different amounts in different places, never a good idea if you'd like a rectangular door!
One other thing to consider. If you glue up three boards to make a panel which sits in a groove in a frame, then the frame will try to resist cupping movement to some extent. The thinner your panel is, the more likely the frame can help here.
Why don't you take a few boards in from your shed and put them in the room where the final piece might live? Don't stack them one on top of the other without spacers to allow the air to circulate round them. After 3 or 4 days, see how they behave. Some might stay pretty flat, others will cup like mad. Use the good ones! But you need to know that once you thin down a piece of wood, you can release internal stresses which change the way it behaves. So you'd want to repeat this process to weed out the boards which don't want to co-operate.
).1. All wood moves around as the humidity in the air changes, and it always changes except in an expensively climate-controlled building like a museum.
2. Along the direction of the grain it hardly moves at all.
3. Across the grain it can move quite a lot. If, when you look at the end of a board, the grain looks like this - ||||||||||||| - then that will expand and contract the least. This is vertical grain. The more those grain lines seen from the end move towards the horizontal, the more the board will move widthways.
4. If the end grain is curved, then each part of it will expand different amounts. With more humidity it will tend to cup towards the inside of the curve, and as humidity reduces it will flatten out again. It will also expand and contract widthways of course.
5. Different wood species do this more or less. Mahogany is pretty stable (though it still moves), while oak moves much more.
So, applying these to your top design, you can see where the expansion and contraction will take place. You have to allow for that. What you have there is effectively a frame with two panels let into it (each panel made of three boards. That panel will get wider and thinner as humidity increases and decreases, and if it is all glued together this will push the frame apart, or pull it in and cause cracks in the panel. So your panel needs to float in a groove in the frame, which has enough space to allow for the movement. I'd guess that if you edge joint the three boards to make a panel, the whole thing might move as much as 5 or 6 mm, maybe even a little more.
The other thing to consider for this design is the end grain on the panels. If they are all going to cup, then you can reduce the overall effect by alternating the cup direction. If all your board will cup in the same direction, the cumulative effect will be huge! Ideally, you would select the boards for these panels so that they will cup the least possible amount.
Looking at your second design, the panel of three boards set vertically will expand in a different direction from the three set horizontally. Together, they will try to expand your door both widthways and lengthways, and different amounts in different places, never a good idea if you'd like a rectangular door!
One other thing to consider. If you glue up three boards to make a panel which sits in a groove in a frame, then the frame will try to resist cupping movement to some extent. The thinner your panel is, the more likely the frame can help here.
Why don't you take a few boards in from your shed and put them in the room where the final piece might live? Don't stack them one on top of the other without spacers to allow the air to circulate round them. After 3 or 4 days, see how they behave. Some might stay pretty flat, others will cup like mad. Use the good ones! But you need to know that once you thin down a piece of wood, you can release internal stresses which change the way it behaves. So you'd want to repeat this process to weed out the boards which don't want to co-operate.
prof chris has explained it perfectly. Just note that in your picture 1, you need a cross piece at the bottom of the door (on the right in your pic) as well as the ones on the top and the middle. Otherwise the panel, composed of three pieces of your original wood, will fall out. It may not be glued or nailed in to the frames or the sides, as chris has explained.
This article may help to explain it: https://en.wikipedia.org/wiki/Frame_and_panel. This describes a simple frame with a single panel. You are making a bigger one, so you need a frame with a middle rail to support two panels.
There is ample information on woodwork construction methods available on the web or in books. Robert Wearing books are classics.
There is nothing necessarily wrong with your boards. I've used plenty of floorboards for woodworking, and often they are far better seasoned than that which you buy in stores. But it it hopelessly uneconomic just to use the central piece of each log, so the grain will inevitably vary in direction, spacing and curvature from board to board. Woodworkers have to learn to live and work with this, and the techniques for so doing have been worked out over millennia!
This article may help to explain it: https://en.wikipedia.org/wiki/Frame_and_panel. This describes a simple frame with a single panel. You are making a bigger one, so you need a frame with a middle rail to support two panels.
There is ample information on woodwork construction methods available on the web or in books. Robert Wearing books are classics.
There is nothing necessarily wrong with your boards. I've used plenty of floorboards for woodworking, and often they are far better seasoned than that which you buy in stores. But it it hopelessly uneconomic just to use the central piece of each log, so the grain will inevitably vary in direction, spacing and curvature from board to board. Woodworkers have to learn to live and work with this, and the techniques for so doing have been worked out over millennia!
thetyreman
Established Member
another important factor is that when using hand tools, you certainly won't get the time back, it's very time consuming so either do it right or don't bother, you would not feel good if you made something that started warping or distorting badly and it could even put you off for life, everyone else has given you really good feedback.
I’m back with more silly questions.
First, I think I'm going to make something easier and smaller with these floorboards. A chest of drawers probably.
How about glueing/laminating to make thicker stock for legs and such.. Is it acceptable practice? How about this type of wood sandwich to make thicker and longer boards?
First, I think I'm going to make something easier and smaller with these floorboards. A chest of drawers probably.
How about glueing/laminating to make thicker stock for legs and such.. Is it acceptable practice? How about this type of wood sandwich to make thicker and longer boards?
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profchris
Established Member
You have two considerations:
Strength against bending forces. Those are weak end-to-end joints, but a scarfed joint would likely be strong enough, particularly with the overlaps staggered.
Appearance. This one is up to you, maybe make a test joint, finish it and then see how you feel about the result being on show.
Strength against bending forces. Those are weak end-to-end joints, but a scarfed joint would likely be strong enough, particularly with the overlaps staggered.
Appearance. This one is up to you, maybe make a test joint, finish it and then see how you feel about the result being on show.
I'm about to glue my first panel with these boards, most of them have this type of grain. I made a crude drawing, on one side you have almost vertical grain on the other there is round pattern. I dont know what it's called.
Should I try to match vertical grain side with vertical and round with round?
Should I try to match vertical grain side with vertical and round with round?
