JWST mirror - Scale 1:1

[Chriske]

Just started building a full scale model of JWST's mirror.
It will be the show-piece of our next open door at our observatory mid September.
Yep, that thing is 6.5m high...

Now that I come to think of it, I should not use the word 'scale' but rather 'copy'...😄

Edited July 20 by Chriske

[Chriske]

First test were very disappointing.
Using 3mm plywood resulted in very bad  surface quality, Even after applying a few coats of varnish.
The idea was (after varnishing and sanding) to add a layer of (high)glossy gold vinyl.

So now plan 'B' is to use sheets of acryl. Acryl has a very flat surface. Did already a small test and it looks promising.

 

[PeterStudz]

This sounds great! 
 

Something like acrylic is probably a better solution. The only way that I’ve found/know for simply sealing wood like plywood for a smooth and non-porous surface goes back to my model airplane days. This involved sticking down tissue paper to the plywood and sealing it with cellulose sanding sealer. Then sanding it down, applying more sealer, sanding… repeat, until you got a smooth surface. The result is waterproof too. 

Works on something very porous like balsa wood too. Of course to get something shinny smooth requires some effort with the sanding. However, I used it quite recently to seal and smooth the edges of 18mm plywood for my Dob base and EQ platform. Worked a treat and easier/better than edging with something like veneer. 
 

Anyway, good luck. I look forward to seeing this when it’s finished!

[Owmuchonomy]

That is some project.  We have a fortunate coincidence in that our Planetarium dome is 6.5m in diameter.  We have an animation which resolves into a full scale image of the JWST primary and secondary mirror onto the dome.  This usually creates some gasps across the audience when they grasp the unfolded size.  We also have the kitchen splash back in black and gold hexagonal ceramic tiles to resemble the JWST mirror in space.

[Chriske]

On 12/06/2024 at 12:55, Owmuchonomy said:

We have an animation which resolves into a full scale image of the JWST primary and secondary mirror onto the dome.  This usually creates some gasps across the audience when they grasp the unfolded size.

Wooow...! Nice idea...!👍

[Chriske]

Change of plan : Plan 'C' is to buy sheets of acrylic that has a 'standard' glossy gold finish on it's surface.

[Dr_Ju_ju]

If you don't want to 'full-scale' then there are 3D printable models available, that can be scaled up, e.g.   https://www.printables.com/model/109816-unfolding-james-webb-space-telescope-jwst

 

[Chriske]

I already made a  JWST scale model 1:7...😉

[Chriske]

This is the 'final' product, the first version is just 4.2m high because the room were it is stored during our open door is only that high.
After open door it will be relocated to our planetarium were the full height will be installed. 6.5m

[Stu]

28 minutes ago, Chriske said:

This is the 'final' product, the first version is just 4.2m high because the room were it is stored during our open door is only that high.
After open door it will be relocated to our planetarium were the full height will be installed. 6.5m

What? You mean it doesn’t unfurl??

More seriously, another amazing piece of work, looks fabulous and love the poses 🤣👍

[Chriske]

Btw the curly boy in the mirror's reflection holding the camera is me. In real I am not that curly...😁

[Chriske]

The mirrors are a bit deformed because we have tilted the complete set 15° forward.

When the mirrors will be relocated to it's final destination all will be installed perfectly vertical and the deformations will disappear.

[900SL]

Incredible.

 

Bravo!

[Chriske]

Today the secondary mirror will be installed
It has a diameter of 800mm, Also gold coated.