Last week I saw on the bus a visible weld in the pipes that you hold on not to fall (often the welds are covered) and so it occurred to me that it would be interesting to see if the structure of the scaffolding would be extraordinarily resistant even with the welds instead of the clamps.

The welding had interested me and brought me back to the scaffolding for the simple fact that it was the conguintion between metal pipes in a public environment.
I hadn’t found any scrap in the lab that would go well, so I did a test with two small pieces of a tube that I found. I didn’t care about the finish of the weld but the strength it can hold.

Tuesday I went to buy mild steel tubes to start experimenting with everyday objects like a stool that hold the weight of the body.
My intention is to try to bring the language of scaffolding back into an object that could be at home.

Will the language be recognizable even without the clamp that characterizes the scaffolding?

On Wednesday morning I went to the metal workshop to start making the load-bearing structure I had designed. I made some sketches on how I could reinterpret the scaffolding system in a seat.

the stool on the middle-right side is the one choosed

I had my metal pipes cut into three 1-meter pieces, 16 mm outside diameter.
Having to make a model in scale 1:3 I used 8 pieces of 20 cm each.
Since the diameter of the poles for the scaffolding is 45 mm, I looked for a diameter that was more or less 1/3 to be able to work with the right proportions.

The first step was to cut the other 8 tubes with a circular saw.
Then I smoothed the burrs that had been created at the ends with a circular sander.

To assemble them I decided to first make two “u” and then connect them with the other two tubes.

My intention was of course to create a structure as orthogonal as possible with the means I had. The first “u” was created using a block of metal that I had found that I used to create the 90-degree angle.
I managed to get a good result but I wanted to try to improve the technique to put them perpendicular.

Then I found an orthogonal clamp that seemed to be right for me. I leaned the tubes and, under the highest one, I leaned another one in order to have it perfectly aligned.

The result of the welding was optimal but I was not able to perform the other welding to complete the “u” because the start already welded impeded it. I’d need a bigger clamp to get the sides in.

At this point I had to find a way to place the two “u” at the same height to weld the other two sides that would create the final volume.
Initially I decided to use two very large clamps where I could only place one of the legs and therefore its stability and “precision” was very weak.

I then tried to stop all four legs by putting a vice on each leg. It was definitely much more stable than the first solution but, after adjusting it perfectly, I realized that it was still not very stable and I was afraid that during welding it could move and ruin the whole process.

So I started looking around again and found these magnetic arrows with a hole in the center.
The magnet being very powerful managed to hold the structure in place.

The reason why I soldered near the end of the pipe but not at the top, thus creating this “intertwining of pipes”, is to resume the language of scaffolding that are assembled in this way for the types of joints that are used.

The metal structure is finished, now missing the wooden parts to be inserted in all ends of the pipes.
I decided to try to make these inserts with the lathe to get a nice finish and also to try to make different power amps.
Since the lathe was booked by another guy and I wanted to see finished my stool I decided to use the waste wood that there is in the laboratory.

I used wooden cylinders with a diameter of 15 mm, almost perfect for my tube (16 mm).
From these, however, I had to subtract part of the diameter to be able to have the interlocking inside the tube. To do this, not having the lathe, I used the circular sander using the part where the disc ends to have a 13 mm part that fits into the tube.

I cut them longer to be able to adjust the height (of the part out of the tube) later and especially to have a better grip on the cylinder to the circular sander.
At the 4 cylinders at the end I decided to attach a square of wood of 40 mm side and a little less than a centimeter thick to recreate the platforms on which the scaffolding rests and that give greater stability to the entire structure.

I chamfered the platform to make it less static and more elaborate.
And then glued them to the cylindrical inserts.

The elements that I created after were the “caps” for the tubes that end horizontally, these are not part of the language of scaffolding but I wanted to add them because they give completeness to the design. Each tube ends with a wooden part and also, thinking of a full-scale stool would also be a protection for direct contact with the metal.

Also for these I used the same technique that I had used for the feet: cutting the wooden cylinder of 15 mm, reducing the diamentro and finally cut the desired size.
I’d like to give it other shapes to these 8 endings, if they connect together in pairs as to pass around the corner? or if instead they were only a part of protection and decoration? In the scaffolding there is a “case” for the junctions and for the clamps. Maybe I can try to use the same language.

The next step was to do the part of the sitting. The session is composed of 4 inserts (such as feet) and a plane that connects them. The plane will be as large as the square that is formed by taking the ends of the horizontal tubes to which the “cap” has already been inserted.
The only fairly large piece I found in the laboratory to make the top was a light grey laminate of plywood (220 mm x 220 mm x 15 mm).

Positioned the structure on the plane I traced the point where the holes were to be made (not through) in the plane where the cylindrical inserts would be placed.
The holes were made of 16 mm so as to have a minimum thickness of defect in which enter the cylinders of 15 mm.
Once the holes had been drilled, the structure fitted perfectly. I tried to turn the plane and see if it would be stuck anyway but this was not because, as precise as the structure was, the least erorre did not return the joints.

I wanted to give the floor a chamfer like the platforms of the feet but in the opposite direction. So I placed the circular sander at 45 degrees and marked the points up to which I wanted to sand on the plane. The final result of the chamfering gave, in my opinion, an extra touch to the stool. The fact that it was laminated plywood also created a special effect by showing the layers of wood in 45 degrees.

The last step was to glue the plane to the cylindrical dowels. I put some weights on top and the gluing was perfect. I checked before that the plane was in the bubble and that therefore the structure itself was built correctly.

The final result needs some consideration.

  • The metal structure has the strength I was looking for because, going up with all my weight, it manages to hold perfectly (even with the wooden top above that rests on top of the wood inserts and on the legs).
  • the wood is all recovered and therefore has limited the final result (now I want to do all the finals with the lathe to be able to give it a greater value and play with the forms in revolution)
  • I had deliberately made the welds with little attention but with the intention of having strong conguinals. That was the case, but I would like to try and make it even better. Being a 2 mm thick tube at one point it even punctured during welding and this is definitely to be avoided.
    Next time I want to do some welding tests first to be able to adjust the gas in the best way and try to keep the welds less visible.
  • do the welds have the same capacity as the clamps? are they better or worse? surely the main difference is that one can be disassembled and the other can’t. But which one is more resistant to weight?
    In scaffolding of course welding is not even considered as there is a need to assemble and dismantle.

The final result satisfies me, even for the time of realization, but I do not know if the reference to the scaffolding is recognizable even by someone who knows nothing about my research. Probably not… I have to verify.
I like its aesthetics but I am not convinced, I would like to see it with the turned parts (next step).
What other elements can I add of this language?

  • the joint covers
  • Blue and red nets
  • wood of scaffolding
  • Adjustable legs
  • clamps