Wheel mount (spannelement) came loose again!

[RonPeeters]

Just as in this post my left wheel came loose again for the third time! This time I was not at home...
Is there another solution for mounting the standard wheel then the clamp coupling? My drive axles have a flattened side, maybe that is better used in another wheel mount?

The result in the grass:

 

[holunder]

Is the clamp properly tightened before the wheel is mounted? With me they are so tight that I have problems getting them down again.
Put the clamp on, tighten the upper part with 4 screws (screws as tight as possible), remove the screws, put the wheel on, screw tight.
Secure the screws on the bike with a little locking varnish, otherwise they could loosen during operation, which could result in the clamp loosening.

 

[RonPeeters]

The problem is not the tensioning method, but thanks for the explanation.
After tensioning the wheel is somewhat connected, but after a few hours it comes loose again. Loose does not mean the wheel falls off, but that the motor turns and the wheel stands still.
Material has been scraped off the axle by the clamp (spannelement). The same happened in this forum post and includes a picture.

I will look into ordering a new set of clamps and look into alternatives. I am not willing to buy a new set of motors, only when a bit is scraped off the axle...

 

[holunder]

You could look for something like "8mm motorflansch", which you can secure to the shaft with a screw. But be sure to secure the screw, otherwise it will loosen very quickly.
You would also have to cut threads for the wheel attachment.



maybe this will help you.

What happens if you coat the shaft with locking varnish (Loctite 270) before you put on the clamp?

 

[Fürst Ruprecht]

Normalerweise nutzt man bei der Verschraubung von Kunststoffen (wegen dem Setzungseffekt) Metallbuchen.
Bei mir hat aber der Einsatz von Federscheiben ausgereicht.
Trotzdem habe ich auch die 8mm Motorflansche besorgt. Diese haben allerdings keine passenden Bohrungen und müssen überarbeitet werden.
Gruß Fürst Ruprecht

 

[flyfast]

I used a Loctite 270.
No loose wheel adapter since then.

Uwe

 

[RonPeeters]

I used a Loctite 270.
No loose wheel adapter since then.

Uwe

On the original spannelement?

 

[flyfast]

yes

 

[RonPeeters]

New wheel mounts are ordered at the shop.
The loctite Idea on the axle is also a good one, will definitely try that!

 

[RonPeeters]

The new wheel mount came in from the ardumower shop. Added some loctite 270 to the combination and the wheel seems to be mounted good. But time will tell...

 

[AlexanderG]

I fixed it (as a temporary solution) by adding a heat shrink tubing over the inner clamping element :

Chassis 2021 – www.wiki.ardumower.de

wiki.ardumower.de

 

[Fürst Ruprecht]

For those who have the same problem, I fixed it by adding a heat shrink tubing over the inner clamping element (after that the clamping element will tighten the shaft again):
Anhang anzeigen 2992

(have added this to the Wiki):

Chassis 2021 – www.wiki.ardumower.de

wiki.ardumower.de

Also ehrlich, das ist eine Frickellösung. Der Schrumpfschlauch ist und bleibt ein weiches Material. Der hat in einer Klemmbefestigung nichts verloren. Das kann auf Dauer nicht halten. Bei dieser Art der Befestigung, also dem Klemmelement, muß dafür gesorgt werden, daß immer ein Moment anliegt. Normalerweise übernehmen das die Schrauben durch ihr Anzugsmoment. Wenn ein Kunststoff(rad) mit verschraubt wird, wird der recht schnell wegfließen und das Moment fällt ab, das Rad bzw. Spannelement löst sich. Die Schrauben lösen sich nur, weil sich die Verbindung setzt, das Moment verloren geht. Festkleben ändert das nicht, es kann vielleicht den Prozeß etwas verlangsamen.
Gruß Fürst Ruprecht

 

[AlexanderG]

Leuchtet ein und daher habe ich noch ergänzt dass dies nur eine temporäre Lösung sein kann (beim nächsten Mal geht's direkt zum Schraubstock). Schauen wir mal wie lange sie hier hält...

 

[RonPeeters]

I must agree with @Fürst Ruprecht
The best solution would be this type of mount (see picture), but I am unable to find it with a 8mm d-bore.
The high power engines that the Ardumower has should have an equally powerfull wheel mount.

My new 'spannelement' currently is becoming looser again, you can feel it when you turn the wheel manually. I will post an update if I find a good solution.

 

[AlexanderG]

Have you considered pressing together the outer clamping element in a bench vise? Another idea is to use a filling under the 'ring'. Soda/beer can strip works fine for that (both methods have been reported by users to work if the motor shaft has slightly reduced diameter).

 

[RonPeeters]

Have you considered pressing together the outer clamping element in a bench vise?

Yes I have. The result is good, short term. It opens up again. Did not heat the material though.

All the repair options you mention are worth trying, but do not feel like a permanent solution to me.