Yaffles

Looks very nice.

 

Laminated ply might be an option for the circular lining.  Not too hard to do, with a carefully scarfed joint on the inside edge to blend it in.  Could even just give it a varnished or oiled finish if you use ply with a nice surface veneer.  There was a curved staircase on one of the house build TV shows a few years ago that used laminated ply and it looked very nice indeed when it was finished.  IIRC they used a boatbuilder to make it, as laminating curves is bread and butter work for them.

Wow, they look spectacular! Am so pleased for you that things came to a good conclusion. The round one in particular!

Looks fantastic, would second what Jeremy says about ply being a very good option. Plastics would also work  but I have no experience or examples in this but could be looked into if wood was not possible for some unknown reason. 

Looks fantastic. well done!

Ply looks good and would be able to be finished nicely.  I guess we could shove some insulation behind it in the gaps.

I also found this bendy plasterboard:

https://vcut.co.uk/services/flexiboard/

Anyone used this stuff?

@Onoff what you say...looks like a fairly simple framing job to accept the bendy plasterboard but and it's a big BUT it will have to be dead on to look classy.

The edges of the framework touch the edge in some places...just nearly in others. A travelling @JSHarris is your man...eye to detail crucial.

What's the diameter of the glass inside? Thinking if less than a standard sheet you could do three templates in 22mm ply with a perfect circle and screw into place...?

Edited November 13, 2018 by Tennentslager

Flexible plasterboard in two 6mm layers. Gyproc do one. V-Cut is another make. There's a thread somewhere where @jamiehamy did a curved wall.

 

Maybe flexible MDF underneath for strength. 

Crossed post on the V-Cut, I was still typing my post! 

 

For a perfect circle you could get ply or MDF sheets water jet cut then space them up the hole then just "line" with the flexible sheets.

Where is @jamiehamy we've not heard from you for a while ??

Had just found the @jamiehamythread.  That wall looks really good.  

Will look at the flexi 6mm plasterboard.  

 

@Tennentslager Internal diameter is 1830mm.  Don't think I am going to get that templated in one piece?  

Just playing. Connect the red bits of wood with long studding? Green is the flexi layers

 

 

 

Gotta love spending other people's money!

16 minutes ago, Weebles said:

@Tennentslager Internal diameter is 1830mm.  Don't think I am going to get that templated in one piece?  

On second thoughts it might be a burger to fit a single piece in place. I think you know you need a committed joiner who likes a challenge but it is perfectly doable ???

23 minutes ago, Weebles said:

Had just found the @jamiehamythread.  That wall looks really good.  

Will look at the flexi 6mm plasterboard.  

 

@Tennentslager Internal diameter is 1830mm.  Don't think I am going to get that templated in one piece?  

 

1830mm to the internal plastered faces?

Fabulous!  So pleased they're in at last, it's been a long hard wait.  I can offer no practical advice on finishing the circular window, but can't wait to see it all boarded out.

7 minutes ago, Onoff said:

 

1830mm to the internal plastered faces?

 

1830mm to the current timber face.  

Loving the sketch.  My joiner (long suffering husband) is up for a challenge.  He's done nothing more complicated than a toilet box out so far but he's learning on the job!  ?

(someone else will be helping put up the plasterboard as we hope to be in before Christmas 2019 ?)

Make accurate 4-piece sandwiches for each "ring"? Then all bolts & glues together. Circle here is 1830mm dia but can change easily

 

He's slumped on the sofa, rolling his eyes......

He has some days off over Christmas so I think this will keep him occupied?

Say 3 "support" rings, each made from 8 identical bits of "mdf or ply.

 

12 bits per sheet so two sheets gives 24 pieces - enough for 3 rings:

 

Little wastage. Could clamp two sheets together and jigsaw but cries out for laser or water jet imo:

 

 

Orientate:

 

 

Clamp/glue/screw. They're 1830 across flats. Inner circle to suit:

 

 

Edited November 13, 2018 by Onoff

They look really great, you will be pleased to get that job done.

39 minutes ago, Onoff said:

Say 3 "support" rings, each made from 8 identical bits of "mdf or ply.

 

12 bits per sheet so two sheets gives 24 pieces - enough for 3 rings:

 

Little wastage. Could clamp two sheets together and jigsaw but cries out for laser or water jet imo:

 

 

Orientate:

 

 

Clamp/glue/screw. They're 1830 across flats. Inner circle to suit:

 

 

 

@Onoff What are you doing next weekend?

 

How would you fix the bendy plasterboard to the mdf / ply (which I am assuming is only 12-15mm deep)?

2 minutes ago, Weebles said:

 

@Onoff What are you doing next weekend?

 

How would you fix the bendy plasterboard to the mdf / ply (which I am assuming is only 12-15mm deep)?

 

Tiling!

 

Ply as drawn is 25mm as in each "eigth" is 12.5mm ply. Work in progress this but I can CAD it up. Well worth thinking about asking a local water jet cutter to you. You'd get a super accurate kit of parts to just assemble. I could do a DXF file the water jetters could put straight on their machine.

Genius.  What are you wasting your time with tiling for??

 

Will talk to the resident joiner and the tacker.  Thank you.

 

10 minutes ago, Weebles said:

Genius.  What are you wasting your time with tiling for??

 

Will talk to the resident joiner and the tacker.  Thank you.

 

 

Have a phone around and see who'll cut MDF/ply. Just a quick Google near you and there's London Water Jet, Rapid Laser, Middlesex Laser and so on. Engraving type places might not be able to cope with an 8'x4" sheet btw. Out of interest if you cut MDF with a water jet the edges swell a tad then shrink back!

 

We can easily knock up something on CAD if you want and I'm sure the collective will have plenty of input.

 

HTF will you get it up? Scaffold tower and assemble in situ?

 

I'd likely Sikaflx and pin the MDF to the 25mm edges. Bendy pb to that with pb screws and let the spread do his magic after.

Pb will rely on a skimmer or filler doing a good job.

1 hour ago, Oz07 said:

Pb will rely on a skimmer or filler doing a good job.

 

It will, and I reckon it would be easier to laminate thin ply around an internal cylindrical mould, with a long scarf joint on the inner joint to ensure a dead smooth internal surface. 

 

I made a hovercraft duct up this way years ago and it worked OK, with the smooth inner surface true to within a couple of mm, as the fan only had around 3mm tip clearance.   It'd need good quality ply, as the cheaper stuff may well have internal voids that will stop it taking an even curve, but wouldn't take long to make.  Probably take longer to cut out three or four MDF discs to make the form than it would to bend and glue the ply around it.  The ply needs to be held in place with ratchet straps whilst the adhesive cures/dries, and it's best to use a slow curing/drying adhesive to allow time to gradually tighten up the ply laminate.  It also needs the sheets of ply to be scarf jointed together before hand, to make a strong continuous length, but that's easy to do with a long scarf jig and a plane.