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PaulsInnerChild
13th September 2008, 12:42 AM
Hi am new and currently I am building a Stevenson Screen. It is a big challange and I even cut the slots with a router to fit all the louvres in
Mine is not exactly the same design as the one below but it still has a double layer
of louvres and I am building it out of red cedar and painting it white. Yes they must be white. Mine will also have a pitched room and the internal demensions between between the inner louvres will be as follows.
I

Conditions & Requirements



Double layered roof with ventilation provision.




The screen shall comply with IS 5948 – 1970.




All dimension requirements shall be met within 5% of specified dimension.

Specifications
1.


Standard width

length between inner slats of louvers 560 mm
width between inner slats of louvers


315 mm

height between middle of lower roof and floor


412 mm


The one below is a bit more compact than those specifications but mine will be the same if I can manage to pull it off because it is the first time I used a router. But so far so good. I will post a picture of it if I get is finished.


http://www.up.ac.za/academic/geog/community/stev%20screen.jpg

Ed Reiss
13th September 2008, 12:35 PM
Hi PaulsInnerChild....and welcome!

Clue me in...what is a Stevenson Screen?:?

Cheers,

Ed :D

Hoodie
13th September 2008, 02:27 PM
G'day Paul and welcome.
A Stevenson screen will be an interesting project. Hope you like routing dado's for all the louvres. Bit of a shame to paint that cedar white but you must do what is necessary for the instrument. At least it will last a while. don't forget a pic or two when you finish.

A stevenson scren for those that don't know is a container for a weather station, must have full flow ventilation , insulated roof, the slats must be angled to keep out rain etc. the expession "it's 40º in the shade " is what these little beauties are all about.

Cheers
Baz

PaulsInnerChild
13th September 2008, 07:58 PM
G'day Paul and welcome.
A Stevenson screen will be an interesting project. Hope you like routing dado's for all the louvres. Bit of a shame to paint that cedar white but you must do what is necessary for the instrument. At least it will last a while. don't forget a pic or two when you finish.

A stevenson scren for those that don't know is a container for a weather station, must have full flow ventilation , insulated roof, the slats must be angled to keep out rain etc. the expession "it's 40º in the shade " is what these little beauties are all about.

Cheers
Baz

Hi All
All the routing for the louvres was completed today and I used a template to help guide the router through the slots.
Later I need to make to double roof and floor with long routed slots to aid better ventilation
I will assemble the back and two side walls maybe tomorrow. The louvres themselves are 6 mm thick and 12 mm apart and all angled 45º
I hope to have it up in a couple of weeks

Cheers :cheers2:

bluegum30
13th September 2008, 11:41 PM
why did you use red cedar ,did it have something to do with efficenty of the stevenson screen.:)

lloyd.

PaulsInnerChild
14th September 2008, 12:25 AM
why did you use red cedar ,did it have something to do with efficenty of the stevenson screen.:)

lloyd.

The ones I have seen were made out of red cedar. I think it is because cedar is a better insulator and very durable. All that aside it was very easy on the router bit and it is just as sharp as it was before I made 300 cuts with it.. The cedar slats I got from a community shed for free so I made the rest of it with cedar. BTW The Bureau of Metorology screens are made out of red cedar also so it may have something to do with the efficenty of the screen. :rain2:

underfoot
14th September 2008, 06:39 AM
why did you use red cedar ,
lloyd.

I'm assuming you are referring to the "other" (western) red ceder.' Thuja plicata'
not Australian red cedar 'Toona australis',
our home grown stuff won't last long in those conditions

munruben
14th September 2008, 02:33 PM
Welcome. Interesting project. Look forward to those pics.

PaulsInnerChild
14th September 2008, 03:58 PM
Hi
I am working on it at a leasurly pace this afternoon. The back louvres a nice and evenly spaced but the side louvres are not quite as well evenly spaced as I would like, but not too noticable. Assembling the louvres together without frustratingly falling to pieces and keep starting over and over again was the part I most dreaded but I am managing OK with difficultly. I have the back wall all in one piece.

:cheers:

AlexS
14th September 2008, 06:31 PM
G'day, That is an interesting project.
The BoM (and other commercially available ones) are made from WRC because of its durablity.
Are you setting up a home weather station, or do you have a professional interest? The BoM website has details of where some of the instruments should be located inside the screen, also heights above ground etc., but you probably knew that.
Cheers & welcome.

PaulsInnerChild
15th September 2008, 12:27 AM
I have just an obsessive interest in meteorology me having asperger syndrome and this is the biggest woodworking project I have done since I built a set of kitchen cupboards about 35 years ago. It is certainly the most difficult and I have decided to make a gabled roof instead of a conventional skillion roof the bureau of meteorolgy uses. It does not matter what shape to roof is as long as it is double. But I will have vents on the top of the gables for better ventilation and I am even thinking of finishing it of with some decorative finials as well.

The World Metorolical organization allows for both skillion and gables roofs but there is a fair range of heights the instuments should be up off the ground and that ranges from 1.2 metres to 2 metres. I will mount my instruments somewhere in between at 1.5 metres.

I chose a gabled roof because that just look nicer

Hoodie
15th September 2008, 07:40 PM
G'day Paul
Sounds like you are going well with the construction. Hope all goes well. :2tsup:
What instruments will you be using when it's built and installed?

Cheers
Baz

PaulsInnerChild
15th September 2008, 11:45 PM
G'day Paul
Sounds like you are going well with the construction. Hope all goes well. :2tsup:
What instruments will you be using when it's built and installed?

Cheers
Baz

I have two Dobbie thermometers, one for maximum and one for minimum. I may be considering others like a hygrometer to measure relative humidity.

PaulsInnerChild
19th September 2008, 04:04 PM
http://img233.imageshack.us/img233/8793/stevscreen1vl5.jpg

http://img232.imageshack.us/img232/1288/stevscreen2oa2.jpg

I just completed three walls and the door and I will be working on the floor and ceiling and gabled roof later this week. It was realling frustrating getting the three walls assembled together.
:cheers:
Paul

Hoodie
19th September 2008, 05:14 PM
G'day Paul
Looking good mate and thanks for the pics! :2tsup:
Cheers
Baz

bluegum30
19th September 2008, 08:49 PM
g'day Paul ,i can see what you mean by difficult though you appear to have it under control by the pictures,i got to thinking about the screen and i think there is one at the Q F S.at Kalpower.

Lloyd.:U

PaulsInnerChild
13th October 2008, 09:38 PM
http://img222.imageshack.us/img222/6568/screen1hq9.jpg

http://img235.imageshack.us/img235/2766/screen2fu2.jpg

Just finished the Stevenson Screen and I just need to mount it on top of a 1.2 meter post.

Cheers
Paul

PaulsInnerChild
16th October 2008, 04:31 PM
http://img235.imageshack.us/img235/1460/instruments1dh2.jpg
Here is it with the instruments installed
One maximum and one minimum Dobbie thermometer.
Today it peaked at 21.6 degrees Celcius after a low of 7.8.

Paul

jmk89
16th October 2008, 08:17 PM
Looks good, Paul.

What's the next project?

PaulsInnerChild
21st October 2008, 07:42 PM
Looks good, Paul.

What's the next project?

I have a few going, especially kitchen stuff like chopping boards, recipe book stands and now I am about to work of a knife block that can easily unassemble for easy cleaning. I am thinking of inventing blocks inside a box for the design.
I am also considering to make a toy box pirate chest style with a Jolly Roger routered on the lid or front. I would like to get hold of show close hinges for the safety of childrens fingers and gap so kids will not suffocate if they are locked inside