Pythagoras rules.

[sipi]

This isn't in Thailand but I'm sure many will appreciate it anyway.

So I was tasked to build a car shelter off the shed.

No big deal except it was on sloping land and the rooflines had to match up. And it is an unparallelagram if there is such a thing. And built in post and beam.

The first calculation to dig the first post hole was straight enough. The old 3-4-5 rule. It looked a metre out from every angle but I trusted my tape and set the first post.

From there on I decided to build it kit style, on the ground first, then put into place. So out came the trigonometry tables. I'm sure we all remember the "some old hags can't always hide their old age" jingle.

The final calculation for the last cross member was something like...

 

√tan delta<[π total length]¶∆#rake angle@÷{¥~€}\®^©¢=π°</(tooth depth)...

 

Or something like that.

Anyway it turned out ok.

 

[Crossy]

Seems to have come out OK, no termites there then?

 

Do you need to bung up the holes in the re-used BlueScope?

 

[sipi]

Just now, Crossy said:

Seems to have come out OK, no termites there then?

 

Do you need to bung up the holes in the re-used BlueScope?

 

One day. I recycled the roofing from the outdoor theatre.

The timber is H4 treated pine which is apparently indestructible.

[sipi]

Actually it was more an exercise in trust.

Marking the timbers which weighed a ton on the ground (8"X2" laminated X3; effectively 8"X6") on saw horses and cutting with a mitre saw and then looking at it and thinking "what have you got here?", then lifting into place to find out fitted like a glove was a really strange experience.

[Metropolitian]

'Not impossible, well done chap'                       'oooh.. magnificque! '  

 

[eyecatcher]

Geometry, pythag 3,4,5 6,8,10 is the most common way of setting out all buildings even if you have a trusted "dumpy"

Its rare however that anyone needs to use trig as sliding bevels, string lines, and good old lining in by eye resolves any angle of dangle.

 

Job well done anyway.

[sometimewoodworker]

4 hours ago, sipi said:

Actually it was more an exercise in trust.

Marking the timbers which weighed a ton on the ground (8"X2" laminated X3; effectively 8"X6") on saw horses and cutting with a mitre saw and then looking at it and thinking "what have you got here?", then lifting into place to find out fitted like a glove was a really strange experience.

Did Escher design those?

[Metropolitian]

1 hour ago, sometimewoodworker said:

Did Escher design those?

No. Although you can call it an Escherian design it is not his.

 

The square is an moebius, which was invented a century earlier by August Ferdinand Möbius.

That right-upper fork is from the Impossible Trident Figure and that Trident was created by D. H Schuster, an American psychologist.

 

Roger Hayward, also an American, drawed an stone pillar which resemble the same.

 

[sipi]

7 hours ago, eyecatcher said:

Geometry, pythag 3,4,5 6,8,10 is the most common way of setting out all buildings even if you have a trusted "dumpy"

Its rare however that anyone needs to use trig as sliding bevels, string lines, and good old lining in by eye resolves any angle of dangle.

 

Job well done anyway.

The problem with this little project, I was working on my own with heavy timber on uneven ground. Measure twice, cut once, minimise lifting.

Otherwise I normally use the string line and eyes method.

Edit. And by heavy I mean dang heavy!

Edited January 10, 2020 by sipi

[Metropolitian]

10 hours ago, sipi said:

The problem with this little project, I was working on my own with heavy timber on uneven ground. Measure twice, cut once, minimise lifting.

Otherwise I normally use the string line and eyes method.

Edit. And by heavy I mean dang heavy!

How did you move and erecting them, sledges and pulleys?

Or the way the Egyptians did and you're now left with a huge pile of sand ? ????

[sipi]

50 minutes ago, Metropolitian said:

How did you move and erecting them, sledges and pulleys?

Or the way the Egyptians did and you're now left with a huge pile of sand ? ????

Brute strength and a ladder. I bought one of those gyprock lifters after.

[canopy]

These days you can skip the trig tables and be limited only by our imagination. You sound like someone who could benefit from a computer 3D drawing program. It makes designing something like this a piece of cake and there is no math involved, just draw to ideal. Before I embark on any DIY project no matter how simple or difficult, I first draw it using sketchup. The end result is always improved and the finishing touches you think of during drawing and looking it over can be remarkable.

 

[sipi]

On 1/12/2020 at 10:04 AM, canopy said:

These days you can skip the trig tables and be limited only by our imagination. You sound like someone who could benefit from a computer 3D drawing program. It makes designing something like this a piece of cake and there is no math involved, just draw to ideal. Before I embark on any DIY project no matter how simple or difficult, I first draw it using sketchup. The end result is always improved and the finishing touches you think of during drawing and looking it over can be remarkable.

 

Thanks. I might play with that sometime.

My downfall was the actual cutting. The lines were accurate, I missed them a couple of times. Setting the saw angles and staying on line through all the sawdust...

The pictures don't show it but all of the cuts were angles on angles. The largest gap is about 2mm over a span of about 6mtrs. I haven't had to use gap filler yet.