What ho one and all,

The tenants in my maisonette have broken the Roto tilt/turn window gearbox. And in trying to 'repair' it, they have made a complete mess of the gearbox.

Internet research and I have found a number of alternative gearboxes plus an apparent direct replacement

https://www.amazon.co.uk/Roto-C-100-Centro-Repair-Silver/dp/B07VXB1HSS/ref=d_pd_day0_sccl_1_1/259-3746661-0970849?pd_rd_w=ClNIA&content-id=amzn1.sym.5d35c111-20a8-4b68-a348-a2ed4044ce2d&pf_rd_p=5d35c111-20a8-4b68-a348-a2ed4044ce2d&pf_rd_r=PYWF8KXBNS6SS0KG65PK&pd_rd_wg=UQHc9&pd_rd_r=2ae8503e-d87f-4013-a3e8-cc820801cb46&pd_rd_i=B07VXB1HSS&psc=1

All the other gearboxes screw together so I do understand how the two halves are connected. But the broken one and the above replacement, has two lugs that protrude on the other side with no apparent method of actually fixing the two halves together.

Given the attached photos, is it wise to assume that the centre indent on the lugs is the location to 'pop' with a centre to wedge the halves together?

Thanks and toodle pip.

Not having much luck with a response, I manged to find the email contact for the German Roto company and sent a similar question to their tech department.

This is the reply; really useful!!!!

Dear Sir or Madam,
Thank you for your message.
Unfortunately, we cannot give you any information about the installation. Please contact a window fitter.
We would like to point out that installation/replacement of components/accessories may only be carried out professionally by a specialist or by a specialist company.
We accept no liability for damage to property or persons caused by improper installation/replacement.

As it happens, I have found an alternative gearbox that fits and the two halves screw together. Can only hope that I have sufficient knowledge to screw the track in place without breaking any company liability laws!