Every joint has expanded. But can not be seen on the sides, probably because the veneer stripes run parallel, with the expanded panels.
Not sure where the plywood is made.
You guys have been helpful, next time I know how to make better. I'll probably wait and see how the speakers act. They sound creat, and maybe in the correct place and lighting, this little error can not be seen. If it still annoys me I have to do the veneering again.
I quess the first speakers most likely wont be 100% successful anyway.
Not sure where the plywood is made.
You guys have been helpful, next time I know how to make better. I'll probably wait and see how the speakers act. They sound creat, and maybe in the correct place and lighting, this little error can not be seen. If it still annoys me I have to do the veneering again.
I quess the first speakers most likely wont be 100% successful anyway.
Wood is unnatural, imperfect. I agree you did a pretty good job by the looks of it. Try one of the markers if it bothers you that much. I use them sometimes on say an antique piece of furniture thats opened up here or there, and an inner edje becomes slighly visible. or a situation like yours. The edge will virtually disappear.
If you reapply veneer without correcting the problem, you will get the same outcome.
One way of preventing the edge from telegraphing is to use thicker (1/8"-1/4") single wood sheet veneer across the entire surface to cover the joints. Often you can buy this in the wood species of your choice. Alternatively, you could add a thin sheet of underlay (1/4 sureply) to cover the surface and edges (used under vinyl flooring) before applying extremely thin veneers.
I suspect all side panels lengths are not equal (ie. front=back, and left=right but front<>side). The panel widths (front-back, and left-right) are probably the same from top to bottom so expansion/contraction happens at the same rate along the entire side but not the top-bottom. This is why its showing on the top first, but it can telegraph along any edge.
One way of preventing the edge from telegraphing is to use thicker (1/8"-1/4") single wood sheet veneer across the entire surface to cover the joints. Often you can buy this in the wood species of your choice. Alternatively, you could add a thin sheet of underlay (1/4 sureply) to cover the surface and edges (used under vinyl flooring) before applying extremely thin veneers.
I suspect all side panels lengths are not equal (ie. front=back, and left=right but front<>side). The panel widths (front-back, and left-right) are probably the same from top to bottom so expansion/contraction happens at the same rate along the entire side but not the top-bottom. This is why its showing on the top first, but it can telegraph along any edge.
Generally speaking 13 ply BB should be quite stable in its length and width as the plies oriented with alternating grain direction restrain this movement. It will undergo a modest amount of movement across the thickness axis as the thickness of the plies are radial to the orientation of the wood in the tree. I can see the marks in your top two pix but the third one doesn't show at all and the construction of your box is unclear. If the box under the veneer has exposed BB edge plies glued to the veneer in the areas showing the marks it may be differential movement between the edge plies and the veneer.
Yes, I couldn't see what he was getting at in the third picture, which has disappeared by the way
Screws won’t effect the expansion of the entire panel, but if the boxes have been in the environment that they will be used in, they are not going to change unless the humidity or temperature changes. I use a flush trim router if I can, otherwise sanding works too.
I would re-do it since I know I could fix it, as opposed to factory made stuff, where you don’t know what you are getting into. The re-application of the lacquer would be a bit of a drag though, so I understand just leaving it and enjoying the speakers, which look great btw.
I have a few smaller dents in my car, which read differently depending on the temperature, so every time that happens, they catch my eye, as they’ve changed slightly. Between seasonal changes, I hardly notice as I’ve become used to how they appear...
I would re-do it since I know I could fix it, as opposed to factory made stuff, where you don’t know what you are getting into. The re-application of the lacquer would be a bit of a drag though, so I understand just leaving it and enjoying the speakers, which look great btw.
I have a few smaller dents in my car, which read differently depending on the temperature, so every time that happens, they catch my eye, as they’ve changed slightly. Between seasonal changes, I hardly notice as I’ve become used to how they appear...
Right here. Bad news plywood.
The making of: The Two Towers (a 25 driver Full Range line array)
Starting at post 113.
We have come across this issue before on the forum, quite a few years ago now. It was MDF back then with high gloss painted finish.
A big factor is the use of PVA glue as it allows creep. So my advice to you is either thick veneer or just live with it. No amount of other refinish work will get rid as your foundations are not stable.
Next build try epoxy or urea formaldehyde (powdered resin mix with water) glue.
A big factor is the use of PVA glue as it allows creep. So my advice to you is either thick veneer or just live with it. No amount of other refinish work will get rid as your foundations are not stable.
Next build try epoxy or urea formaldehyde (powdered resin mix with water) glue.
That would be the one Pano.
Ive seen my own work included, were a panel /table top has been glued up sanded and finished with a film finish. Shortly after under certain light a ridge appears along the joint line, problem a flat sawen board was glued to a quarter sawen board causing the later to expand or contract more in its thickness. It can take probably as little as a thou of a inch for the eye to see or finger to feel.
Ive seen my own work included, were a panel /table top has been glued up sanded and finished with a film finish. Shortly after under certain light a ridge appears along the joint line, problem a flat sawen board was glued to a quarter sawen board causing the later to expand or contract more in its thickness. It can take probably as little as a thou of a inch for the eye to see or finger to feel.
The ply didn't open up the veneer came into question, correct? I still think its a good idea to screw a piece of furniture such as a speaker cab thats frequently used. Or a really trusted locking system. Considering you want your workmanship to last twenty five or thirty five years. There is a chance it comes apart much later.
With advancements in bonding agents we wont absolutely know how good glues are until a decade or more passes by.
Lepages is pretty good stuff. The yellow carpenter glue that dries clear. You pay for what your getting usually. Everyone has a favorite.
There are some cheapo white glues out there I stay away from. I did have panels come apart when some was within reach, so thats what I grabbed to use. Never trying it on wood before, it was trusted for paper when I bought it.
Anyone that tells you that "glue is glue" might not of been paying attention.
With advancements in bonding agents we wont absolutely know how good glues are until a decade or more passes by.
Lepages is pretty good stuff. The yellow carpenter glue that dries clear. You pay for what your getting usually. Everyone has a favorite.
There are some cheapo white glues out there I stay away from. I did have panels come apart when some was within reach, so thats what I grabbed to use. Never trying it on wood before, it was trusted for paper when I bought it.
Anyone that tells you that "glue is glue" might not of been paying attention.
Most wood glues have a slight elasticity to them this allows slight movement in the joint which is a plus in most situations, this would not be one of them situations .
There is a glue used for bent lamination or veneering called durobond 90 it dryes very hard and ridged preventing spring back in bent lamination or creep in veneered surfaces. Its 2 part has a shelf life and is not cheep.
There is a glue used for bent lamination or veneering called durobond 90 it dryes very hard and ridged preventing spring back in bent lamination or creep in veneered surfaces. Its 2 part has a shelf life and is not cheep.
The ridge is caused by the top getting thicker. It does not show on the back because the vener bends nicely along the grain. By using a thicker but flexible vener the showing two edges will have a greater radius and not show as much. So sanding and adding even if it telegraphs through again it will not be as visible.
Since there is still some confusion. Sorry for my bad english, hard to explain.
And some people have asked about construction, plus a strange missing third picture. I made an album, with all the pictures I could find about the speakers. Not much, but at least can see something(15 pics). Click on the link, and you should be able to see the images.
Speaker - Google Photos
And some people have asked about construction, plus a strange missing third picture. I made an album, with all the pictures I could find about the speakers. Not much, but at least can see something(15 pics). Click on the link, and you should be able to see the images.
Speaker - Google Photos
If I was in the op's spot I would cut a shalow dado at the offending joints and either paint it black of fill it with some through dyed wood. A saw curf width would do. Maybe mirror the dados aroud the corners or something. Make it look like you intended it to be that way and move on. Gotta roll with the punches when you are dealing with natural materials.
Best way to minimise the effect in the future is to shoot for the middle of the equilibrium moisture content for your area and actually measure the MC of the materials before you start building. A week is okay as a general rule of thumb but if you are dealing with super dry or saturated materials it may not be enough time. One thing you might not find in a quick web search search on moisture content is that the EMC is a function of temperature and relative humidity. In general, the higher the temperature the higher the relative humidity can be and vice versa.
Best way to minimise the effect in the future is to shoot for the middle of the equilibrium moisture content for your area and actually measure the MC of the materials before you start building. A week is okay as a general rule of thumb but if you are dealing with super dry or saturated materials it may not be enough time. One thing you might not find in a quick web search search on moisture content is that the EMC is a function of temperature and relative humidity. In general, the higher the temperature the higher the relative humidity can be and vice versa.
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