StabilobloK 35

StabilobloK 35 is the most advanced cell for 350 mm reflector telescopes, ideal with thin glass (35 mm) and suitable for any optical scheme.

Thanks to some highly technical improvements, this design represents the technological evolution of the  StabilobloK 25 and this cell can be considered the finest for the amateur market.  With this cell the amateur astronomer can totally avoid the problem of optics under-performing because of poor support stability.

The StabilobloK 35, as well as its smaller version (25 series), is designed to remove almost completely any mechanical element of disturbance from the optical structure of the telescope.

With a 350 mm diameter the weight of the glass is quite heavy therefore it is important to arrange its position carefully and, most of all, to make sure that it stays in place throughout the observation. For this reason the StabilobloK 35 has got a very robust mechanical structure also designed to prevent any element which could possibly introduce errors in the mirrors system.

The cell works with 18 floating points designed and made for the purpose. There are no laser or water cut parts, everything has been precision engineered from solid alloy. The design of the cell is the same as the 25 series but loads and tolerances have been adapted accordingly.

The cell has got anti-mirrorshift and anti-mirrorflop systems with a NortheK self-centering function which allows all the elements in contact with the light cone to be kept on axis. It is suitable for focuses from 2,5″.

There are 6 very strong side supports, made with a special structure which can absorb deformations on the contact points and keep the system in balance whenever the edges are not parallel.

The position of the 18 floating points has been designed to minimize the deformation of the optical surface. It is easy to determine the value of these deformations with a simple calculation program. Every vertex of each triangle can work under 50 gr pressure; they are singularly tested on the bench and made operative 35 gr pressure. Thus the system is very reactive. Each joint (BWK2 system) is put under stress for several hours in order to improve the performance keeping the mechanical values unchanged. You will not fin any other mass produced product for the amateur market with the same mechanical accuracy and cost.

The element of innovation StabilobloK 35 cell is a special system for the removal of the boundary layer from the mirror surface. This important result is achieved with the use of 3 extracting fans positioned by the mirror and 3 additional fans at the rear of the cell also assisting in the removal of the layer and the air column. Another option available is the electronic control of the extracting system  (along both the radius and the axis) which we strongly recommend to anyone pursuing the best performance in high resolution.

The setting of the optical plane is done on the production line so that when the product is delivered it is ready for the star test.

Every StabilobloK cell has got  three stainless steel and aluminium shifting systems, larger than the 25 series and with a 0,02 mm accuracy, each with a internal reducer. The activation pivots are made of ground steel and they slide inside self-lubrificating matrix technopolymer systems designed to work in all environments. The end joints are more  advanced than those of the smaller cells. In fact they are made with high precision bearings in sintered steel  and bronze, spring loaded in order to avoid any side movement towards the optical plan. Obviously the springs do not interfere in the flatness of the cell’s plates.

The cells can be personalized upon the customer’s request.

Characteristics Technical specifications
NortheK StabilobloK ST 35
Alloy Halo 25
Metallic composition ISO AlMg4,5n0,7
Chemical composition Si,Mn,Fe,CuTi,Mg,Cr,Zn
Density (gr/cm3) 2,66
Coeff.of Thermal Expansion (10-6 k) 24,2
Degree of roughness N6
Thickness mm +-/0,05
Parallelism mm < 0,1
Planarity mm < 0,2
Shape stability Optimal
Protective anodization Optimal
Surface protection Black anodization
Nuts and bolts Stainless steel
Mirror support system 18 floating point supported by ball joints made of steel and bronze composite
Lateral supports 6 points
Optical plan adjustment Adjustment system in chrome rectified steel 3 points of fine adjustment (0,02 mm) per 120°
Vibrating damping system
Forced ventilation 3 axial extraction fans, 3 radial extraction fans
Customized for different tube Upon request
Weight without optic kg. 10

Specifications may change without notice

Product code: ST 35 Sale unit: piece


Can StabilobloK evolve?

The design of this component has been conceived to allow further updates and improvements.
We would like to remind you that every IMPORTANT technological improvement brings a very high cost increase.
The StabilobloK project can be upgraded not only from an aestethical point of view, it is also possible to improve the performance of both, its structure and accessories.
For instruments with fixed position and diameters between 500 and 800 mm. it is possible to  use more appropriate metallic alloys or specially made steels. The plans adjustment is made with an electronically controlled system the construction tolerances can be dropped down to 0.01 mm. and the thermal expansion can be better controlled with an accurate material selection.
The system for the thermostation of the glass is also more sophisticated, as it incorporates thermometric sensors, automatically controlled systems and refrigerating fluxes.
The lateral supporting systems are self-compensating, while the lower supporting points have an adjustable compensator (alternatively we can offer a more advanced solution with an electromechanical system PC controlled). In the AxyS A2 version the adjustment of the primary’s plan can be made with linear system; in this way iy is possible to re-set the back focus as many times as you want and save all the different positions in the memory. You could modify the field of full light and the necessary extraction in accordance with the characteristics of the shooting sensor and the optical train applied along the back focus. Thermometric sensors and surface refrigerating systems provide all the information to the PC which will optimize all the configurations.
The position of the secondary mirror, that is to say its distance from the primary, is electronically controlled and can be adjusted from the PC.
The primary and secondary baffles are machined  with special instruments from a solid bar in  order to locate the necessary diaphragms with the highest precision.
For this kind of cells we can also provide special customized focus and 4″ and 5″ diameter, they are made in steel, Ergal and Titanium, motorized and PC controlled.
We do not have a catalogue for those products as we manufacture them on customer’s request and modify them in

AxyS A1

High technology support for secondary mirrors.

The supporto for secondary mirrors AxyS  A1 is part of the UnitorK system.
A good reflection optical tube doesn’t need only a good tube structure but also the cell for the primary and the support for the secondary. Most of the performances of the optical system and their characteristics rely on the support for the secondary mirror.
The most important feature for a good support for secondary mirrors is to maintain the collimation with the primary at al times whatever the movements of the optical tube; the second characteristic is to avoid the weight of the secondary support generating torsions or flexions (the AxyS  A1 system can hold secondary mirrors up to 130 mm. minor axis); the last but not least characteristic is to have a clearance to allow the perfect alignment of the light cone.

An advanced system of high precision self-lubrificating pivots for AxyS A1

NortheK technology has solved the problem in a simple way by optimizing carefully every AxyS A1 component and adapting their dimensions in the correct way.
If you have a look at the project, you can notice that this system has the same horizontal movement with 0,01 mm. accuracy as the StabilobloK; it has a double support in Halo 25 alloy which avoid torsion movements even in the case of heavy secondary mirrors; it has a spider with 3 stainless steel spokes with  a wide surface area (1 mm. thick) which effectively strenghthen the system.

0,01 mm. accuracy micrometer essential to find exactly the back focus

It is important to note that AxyS A1 has been designed to avoid the use of glue or adhesives to fix  glass onto metal. Many constructors use glue as it is simple, quite cheap and with no theoretical risks. In reality, the use of glue or bi-adhesives (whatever their elasticity or viscosity) is a serious construction fault. In fact the always cause distortions to the glass surface. This problem often generates astigmatism or other distortions then ascribed to the primary.
AxyS  A1 is a real mini cell, similar to the one used for the support of primary mirrors, but reduced and designed in a way that the glass sheet has some clearance in order not to pass any deformation onto the glass, no matter the temperature of the night of observation. Upon request, it is possible to install an anti-condensation system.

The spider centering system is simple but very precise

Some picture can explain better that words how sophisticated, but simple, the AxyS  A1 support is.

A NortheK exclusivity!

Technical Specifications.

Description AxyS A1, high precision axial support for secondary mirrors
Axial transmission Chromed steel shaft on a technopolymer self-lubrificating bush
Axial movement control of the primary Micrometer with 0,02mm. accuracy, mounted on a steel ball joint
Control of pivoting movement Bronze bushes with stainless steel lock screws
Locking system fot the pivoting movement Manual locking system by steel screws with polymers pads
Axial control Tempered and rectified steel thread sliding on brass
Material of other components Halo 25 alloy
Protection Black hard anodyzation
Optic support Made of Halo 25 alloy with anti-vibration damping system and thermal distortion control
Accessories Self-centrig ring for collimation, anticorodal light shed
Spider 1 mm. thick steel, painted, with optional axial position adiustement
Bolt and screws Stainless steel, Ergal alloy

Data may change without notice

Product code: AxyS A1 Sale unit: piece

Note: included in the sale price are the adjustments to the secondary mirror and to the telescope tube . Please contact us.

Also available for self-construction.
AxyS A1 is the standard version and it can be adapted to the requirements of self-constructor astronomers.
In order to maintain a high quality standard, we recommend to contact In this way we can asses what necessary adjustments to be made are (depending upon the diameters/thicknesses of the glass or the various fitting to the telescope tube).
The A1 version is suitable for secondary mirrors up to a maximum of 130 mm. minor axis.
The A2 version fits secondary mirrors with diameters between 150 and 250 mm. only.
AxyS comes complete with all the electronic accessories fot the PC remote control, in particular, it is possible to check and modify the distance between the primary and the secondary mirrors directly from the PC, as well as centring the secondary thanks to two micrometric actuators, always without leaving your desk.
Every operation can start from a zero reference point set during the assembly or, alternatively, it is possible to save a memory of setting that you can use according to the variables occurring during the shots.