Table- joining acrylic to wood

[marcros]

I really like this table http://refinedelements.com/portfolio-it ... rettyPhoto[gallery_image_1]/0/ (i am not that keen on the wood choice, but the concept I like...)

I have a nice board of brown oak which I think would work well for it.

What would be the best way of fixing the acrylic to the wood, to allow both to move as needed? It also needs to be fixed so that the table doesnt fall over if knocked- would an expoy'd loose tenon in the middle work, and some unglued tenons in slotted mortices work?

Any suggestions about acrylic vs polycarb for this application?

 

[MattRoberts]

Either of those would be fine - it's drillable, so dowels / loose tenons should be fine if have thought. Just need to ensure the tenons aren't too close to the edges, as the acrylic would be quite brittle and susceptible to shear

 

[custard]

Interesting design.

But why is it described as Elm when it's clearly some very nice Rippled Olive Ash? That doesn't inspire confidence, especially as you can tell Ash from Elm with your eyes shut because of the distinctive smell!

 

[marcros]

I am not keen at all on the ash used.

He has done some nice pieces- this is another one that I particularly like, with the cast bronze legs.
http://refinedelements.com/projects/#prettyPhoto[gallery]/8/
http://refinedelements.com/projects/#prettyPhoto[gallery]/7/

 

[Beau]

Would have thought a good sized tenon would suffice. I would use Hi cast acrylic as apparently it is less prone to yellowing and scratching. It's also a lot cheaper. Used lots of it in the past and was easy to work and never had any problems with crazing in spite of the supplier recommending it should be annealed after cutting. Yes it's not as unbreakable but still way better than what's often termed perspex.

Edit. Ignore my last remarks about perspex. A quick Googe shows that it is a hi quality cast acrylic so don't know what it was that I saw that would yellow and go brittle at the drop of hat.

 

[custard]

I am not keen at all on the ash used.

Maybe the maker felt the same way, and thought that if he described Rippled Olive Ash as Waterfall Elm he'd like it better!

 

[Sgian Dubh]

What would be the best way of fixing the acrylic to the wood, to allow both to move as needed?

Assuming you're talking about the acrylic leg at one end of the table, I suspect the most likely means of attachment is a similar arrangement to the bronze leg on the walnut bronze table you also pointed us towards. In other words, a matching clear acrylic T or L shaped meeting point at the top end of the leg which is screwed to the underside of the table top. Acrylic adhesives are available, and I think methyl methacrylate is a fairly common component in them.

So for a T shaped top, you could rout a groove in the underside of top of the T to match the thickness of the vertical leg, and glue this into the groove. Bore some holes in the top of the T, and screw in place, ensuring some sloppiness towards either end for wood movement. You might look at some rubber or plastic grommets to go into somewhat oversized screw holes to spread the load to help reduce localised stress and hopefully reduce the likelihood of cracking the acrylic. Slainte.

 

[woodbrains]

Hello,

Funny thing, taste; I think that rippled olive ash is drop dead gorgeous!

I think the joinery for the mitred end/leg joint would be more of a concern then joining the acrylic leg on. I'm not sure I'd trust biscuits, a plywood spline might be better, but could only be in quite a shallow groove. Secret mitred dovetails?

Mike.

 

[marcros]

yes, funny thing taste. It would be boring if we all liked the same thing.

i have a bit of thickness to the top (about 18mm is the plan, the rough board is a good inch) so i was going to domino it to be honest Mike. Positioned towards the inside of the joint I think that I should be ok. I could do some keys, but the brown oak that I have speaks for itself, so I am reluctant to start adding "in your face" bowties/keys unless I have to.

Secret mitred dovetails are way beyond my skill level.

Richard, thanks for the thoughts on the top. That sounds like a plan!

 

[ED65]

But why is it described as Elm when it's clearly some very nice Rippled Olive Ash? That doesn't inspire confidence...

Neither does the fact that they seem to use the wrong grain orientation on their bowties #-o