Is not your serious or?

I've looked at before buying more instructional videos and etc. Details Reviews.
Also the MDR-post where the inventor of the device showing how it makes.
My first attempt at cutting 1 has failed. A wave-like structure had the wiper blade ....

I thought to myself that I have used the thing wrong.
During the cutting process, whether slow or fast, little pressure or more, you could feel the "bump".

In order to reduce the sliding friction of the device while cutting I simply wets the wiper blades with a touch of Vaseline.

The same sobering result. (See image)
Does shopping for me 2 new wiper. Many Thanks!

I suspect that the installed sound for even soft rubber is not suitable.

For the inventors Adnan Alibegovic and buddy:
An adjustment of the slot width (Spring Loaded) would prevent an evasion of the rubber and thus a 'rattle'.

Unfortunately, I have the power back return because it does not fulfill its purpose for me.