Technical Details - Rondo

Rondo screws are a true alternative to conventional trapezoidal screws. They deliver outstanding efficiency and quiet running due to their round thread profile.  
Made of steel, the lead screws are combined with plastic flange nuts (outer dimensions equal those of standard Speedy flange nuts).



  • standard: stainless steel X20Cr13 (1.4021)
  • on request: aluminium
  • other materials on request


  • standard: EX100 white
  • on request iglidur® J *
  • other materials on request

* iglidur® is a registered trademark of igus® GmbH

Temperature range

  • EX100: –40 to +60 °C
  • iglidur® J: –50 à +90 °C

Nut design

Rondo Flange nut type

One standard nut design has been defined:

  • Flange nut type "RFM"
Other application-specific nut designs can be supplied to customer drawing and in a variety of materials on request including injection-molded solutions.

Lead accuracy


  • ≤ 0,1 mm/300 mm (better than class G9 according to DIN 69051)

On request

  • other lead accuracies



The efficiency η for Rondo round thread lead screws is at about 0.4.

Duty cycle

Load rates, lubrication notice and basic calculation with load factor fL are based on a duty cycle of 10 % for a Rondo made of standard materials.

Factory length

In general, Eichenberger screws are available as threaded rods, approx. 3m long. Upon request, lengths up to 6 m are available, depending on diameter and supply market situation.

Lead screw ends


The lead screws are cut to the desired length without special machining (standard). Upon request, end maching is available. Dimensions are as per customer specifications.


Rondo thread lead screws are precision parts (non-hardened) and must be protected from shock, dirt or moisture when transported or stored. Please do not unpack until ready for use. 

Please check for cleanness when mounting the lead screw unit. Dirt or foreign matter on the thread may cause excessive wear.  

Please consult lubrication recommendation before mounting or operating Rondo lead screws.

Radial loads and torque

Radial loads or torque brought to bear upon the nut result in overload of individual contact surfaces, thus seriously affecting the service life of the lead screw assembly. Therefore it is important to properly mount the screw and to comply with all relevant form and positional tolerances.


In some cases, a single lubrication with grease or oil is sufficient. However, any lubrication cycle depends on the application environment.

Bronze nuts have to be lubricated regularly.

Lubricant used by manufacturer:

  • Klüber Microlube GBU Y 131 - Available Here