Examples of HELIOTECH's previous original designs and production

On the right, my design and technological project of a shrinker strecher from 1996 (Wieslaw Rabiasz).
Body, cast steel,

not cast iron

, cast by lost wax process.
In HELIOTECH production  from 1997 - 2013. These shrinkers stretchers were sold to a German trader
and then all over the world in large quantities.

The photo shows one of the first

brutally tested castings

After that - a few changes in the casting mold: feeding method, speed and direction of solidification and others.
As a result, a very nice, functional and appreciated model was created then.

As of today, that model on the right is structurally obsolete.

There are currently

many copies

of that older model on the market from Europe to America.
Gray iron castings that are cheap to produce and have lower strength.
In addition, there is generally little concern for the accuracy of workmanship, quality and service life of these devices.

The whole product consists of dozens of different important little things

The thickness of the powder coating may vary from time to time
The mounting width, for the shrinking box, the dimension is important here.
It should be accurate in accordance with the technical drawing, then it is necessary to calibrate to size after painting.
Extra time, two fixings on the CNC milling machine - but it's necessary.

"The devil is hidden in the details" :-)

Safety Notes

A strong spring removes any play in the mechanism and keeps the heavy handle in the starting position.
Be careful with possible disassembly. Do not bend over, wear goggles / shield your face.
The spring may "shoot" up and cause a dangerous injury or other damage.

Previous original HELIOTECH project

On the left in the picture, the original HELIOTECH product design. Previous model, improved body.
Burned and CNC milled

from a single piece of steel sheet / plate


This newer model SR90

has long been copied cheaply

, visible on the market - most often as a cast iron.

Never milled from one steel block.

The cast iron "likes" to break off, often near the front pin.

Lost wax process - some details for those interested

Steel casting made by the "melted models" or more commonly called, the lost wax process.
Relatively large element for this technology (about 3 kg,   6,6 lb)
To make this model, it was necessary to make 3 separate injection molds for wax, for three different elements, which were then glued:
- main body
- upper rib
- gating system

This method allows for a beautiful reproduction of the model, along with faithful reproduction of small details and inscriptions.
High accuracy of castings. It is usually used for repeated, larger number of castings.

After years of experience, it turned out, I came to the conclusion that a steel body, milled from a solid steel block, is better than a steel casting,
is a much better solution for compact shrinkers stretchers - despite higher CNC machining costs.