Fixing into birch ply edge

[el_Pedr0]

Hi all,

I'm planning on building a wine rack out of birch ply. Aesthetically, I'd like the rails on which the wine bottles sit to be orientated so that the ply is horizontal. But that would mean fixing the ply rails edge-on to the side supports. The rails will be 18mm ply with a width of 20mm.

Can I screw the rails into the side supports (with careful drilling and countersinking), or am I likely to split them?

But then again maybe it'd look better with the ply vertical - that would then match the ply on the vertical supports. Thoughts?

 

[TheUnicorn]

structurally, as far as i can see you are going to be better off having everything orientated vertically so you are drilling through the layers. aesthetically its a judgement call

 

[el_Pedr0]

Thanks.

Any guesses as to how these rails are fixed? No visible fixings or even plugs. And from other photos of the same construction, they don't appear to be fixed from the other side (i.e. through the side support and then into the rail).

Dowels and glue? There doesn't appear to be vast amounts of contact area for glue, but then again, maybe I tend to overengineer.

 

[TheUnicorn]

at a guess I'd say dowels and glue seems a fair assumption

 

[Stevekane]

What about rebating the bottle supports into the verticles, all done before sliceing them up so that no errors, a good snug fit using the correct router bit with glue fixing it all together?
Steve

 

[el_Pedr0]

Thanks for the suggestion.

Though, I don't know if I'd like the look of rebating because the ply lines in the verticals will then be broken by the rebates. With solid material, I wouldn't have an issue with it. I'll have to give it a go with some off cuts first to see what it looks like.

 

[recipio]

For a relatively cheap display unit like this ( no offence ) I can't see anybody using time consuming joinery. I'd guess a pneumatic nailer with headless pins and glue. They can be awfully hard to see.

 

[ajs]

I'm replying now more as a placeholder that reminded to come back to anything else.

Yes, you can screw into the edge of ply. I've done this at 9mm, never mind 18. Work accurately, use good quality relatively "fast" screws and drill pilot holes. I used "Concept KTX" screws which are my preferred woodscrews. 3mm in that case but at 18 thick I'd probably go up a size or two so the threads engage with more plies.

As for construction in your photo I suspect both members were slotted and interlocked - sorry, can't remember what it's called, been in pub too long.

As for ply in your proposed application, I'm extremely dubious. Ply can make a good horizontal beam provided it's deep enough. In this instance used vertically and with no support along the height I really don't like it. It strikes me as working against the fundamental qualities of the material which is never a good idea. Added to that you have no end of cut ply edges to clean up. Purely on that basis I'd suggest PAR section, I wouldn't have the patience for ply without a good reason.

 

[rogxwhit]

structurally, as far as i can see you are going to be better off having everything orientated vertically so you are drilling through the layers. aesthetically its a judgement call

Actually - I'd let the structure call the tune ... so that's settled, then? The aesthetic will be appropriate by default!

 

[el_Pedr0]

In this instance used vertically and with no support along the height I really don't like it. It strikes me as working against the fundamental qualities of the material which is never a good idea.

The rack in the first post is part of a slightly bigger construction, so the other elements will provide some support. See picture below. Does that provide some reassurance, or would you still be concerned @ajs ?

It was originally going to be in a veneered mdf with the rails in matching solid wood. But doing it in ply is quarter of the cost. I'm hoping that carefully constructed birch ply could actually look thoughtfully designed, vs PAR redwood which risks looking like cheap modules from costco or argos.

 

[el_Pedr0]

slotted and interlocked

What, like some sort of sliding dovetail?

 

[Lorenzl]

Drill and fit thread inserts?

 

[el_Pedr0]

Drill and fit thread inserts?

I'm sorry - I don't understand. The rails must be fixed towards their front end as well as the back end. So with two screws to turn in, you couldn't have a thread protruding from the rail and then spin the whole rail to screw it down into the thread insert. And besides, that action of spinning the rail would be fouled by the other rails. No - I must be on totally the wrong track. Please could you give me a bit more of a pointer.

 

[Spectric]

To dowel and glue that lot would be very time consuming, if I was going to do it then one through dowel with a slat each side. Glue and an 18g brad might be easier and glue can be very strong.

 

[el_Pedr0]

Never used brads before. Is it the kind of thing that you'd have to be looking for to actually notice, or would they be more visible/conspicuous than that?

I must admit, the more I look at that picture I posted in post #3, the more I like the idea of completely hidden fixings. There's 132 of those rails though , so definitely worth exploring the most efficient/easiest/least risky way to do it.

 

[ajs]

What, like some sort of sliding dovetail?

Still can't think what it's called. See the sketch and I hope it makes sense. All cutting is on the flat.

 

[Spectric]

Never used brads before.

They are very fine with a T head and don't leave a hole to fill afterwards, with glue and a brad it will be quick assembly.

 

[ajs]

The rack in the first post is part of a slightly bigger construction, so the other elements will provide some support. See picture below. Does that provide some reassurance, or would you still be concerned @ajs ?

My concern is about sideways forces. From the bottle count it appears we're looking at a unit around 6' tall. Since you have two columns the worst case scenario is when one column is full and the other empty - yes I think you have to expect that in reality if one gets nominated red and the other white or whatever. 70cl of wine plus the bottle must be 1kg a time so each column is 12kg or so load, perhaps translating to 2, 3 or 4kg sideways thrust. My gut feel is that's a lot for a 20mm strip of ply even at 18mm. Even if it doesn't fail catastrophically I'd expect it to start bowing very quickly. A couple of ties horizontally would make me a lot more comfortable but that affects the aesthetics no matter how discreet they may be.

Have you considered reinforcement of some form. An approach that comes to mind would be to route a U channel in the inside edges and slot steel bar in it. 8mm rebar is cheap and will glue in place well although the aesthetic effect of rebar may not be what you want even with discreet placement.

Also consider the supporting structure, in particular up top. Something like this you want to view as hanging from the top as much as propped up from the bottom.

Finally, is this open at both sides? A solid back would do wonders to stiffen it up.

 

[el_Pedr0]

Actually only about 1m high. Each opening for a bottle is about 80mm * 90mm.

Currently open at both sides to reduce visual 'weight' and save on materials. The wider section with shelves has some vertical pieces at the back to provide some shearing stiffness and the wider section with the diagonal members will also provide shearing stiffness. All sections will be fixed together. I recognise, however, that this won't prohibit the vertical members on the very outsides from bowing under the weight of the wine.

Is ply that much more susceptible to bowing than solid timber - e.g. the oak in the professional build in post 3?

 

[Jacob]

.......

Is ply that much more susceptible to bowing than solid timber - e.g. the oak in the professional build in post 3?

Yes.