Let's try to make a square pipe with a cross section of 150 by 150 mm with our own hands from a round PVC pipe with a diameter of 150 mm. To do this, we will need a few more wooden boards or chipboards, as well as a hair dryer, preferably a construction hair dryer, and a hammer. It is advisable to wear gloves on your hands, since the pipe will have to be heated to 140 degrees Celsius.
Preparatory actions
The most important preliminary work that awaits us is to calculate the width of the boards and the thickness of the insert between them to space the round pipe during the process of heating it and transforming it into a square product.
If the spacers are smaller in size, in particular, in width than required, then the pipe will not be completely square, and if the permissible dimensions are exceeded, there is a high probability that it will rupture at the bend points.
The width of the boards must exactly correspond to the side of the inscribed square in a pipe with a diameter of 150 mm, of course, taking into account the thickness of its walls. In our case, the two outer boards should have a width of 112 mm and a length slightly larger than the same size of the pipe.
The insert between them, which we previously called a spacer, taking into account the thickness of the side boards, which is 15 mm, should have a cross-section of 80 by 80 mm and can be composite if there is no array of this size.
Converting a round pipe into a square one
At this stage, a hair dryer comes into play, with which we will heat the material of the round pipe until it softens. Heating must be carried out evenly and the plastic must not be overheated above 140 degrees Celsius, otherwise it may melt, lose its shape and become unsuitable for further transformation.
But before you start heating the inlet part of the round pipe, you need to insert into it elements designed to form a square section. First of all, we insert the side boards along the entire length of the pipe, then between them we insert a spacer with the side on which the bevel is provided, and push it further as far as possible with the strength of only one hand.
Then we begin to uniformly heat the inlet part of the original pipe, gradually moving the heating zone further along its length. In this case, it is necessary to constantly monitor the degree of heating and softening of the plastic with a free gloved hand.
When the flexibility of the pipe becomes sufficient, we take a hammer in our hands and hammer the spacer inward between the two boards. If the process is going slowly, then we again heat the pipe from the inside, outside, and even from its other end.
So we continue to alternate heating and pushing the spacer, helping ourselves with a hammer if necessary, further and further from the beginning of the pipe until the spacer appears from the opposite end.
Now that the elements forming the square cross-section have taken their final position, we continue to heat the plastic with a hairdryer evenly from all sides until the square pipe takes on a finished appearance.
All that remains is, after holding the square pipe for some time on the forming elements until it cools, knock the pieces of wood out of the pipe with a hammer, including at the final stage with the end of the handle.
Result
From a round pipe with a diameter of 150 mm, we obtained a square section of 150×150 mm with slightly rounded corners, which not only gives the pipe an aesthetic appeal, but also makes it stronger, especially when absorbing bending loads.
