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[DG] [DG] autohelm ST 4000 - Printable Version

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+--- Thread: [DG] [DG] autohelm ST 4000 (/showthread.php?tid=6674)



[DG] autohelm ST 4000 - alexandrerua - 09-26-18 05:04 AM

Hi I just recently, bought a minitransat equiped with an autohelm autopilot,
the tiller drive unit was not working properly.
I fully dismount it, and the interior thread was sliding, letting the part that ataches the helm loose.

I understood that some steel [censored] were missing!
I was able to bought some [censored] with the same size.

I want to know if the only thing nedeed is toput them on the bronze part?
how when the thread moves they want fall either side?

can anyone give me some light on that?

thanks.


RE: [DG] autohelm ST 4000 - Derek - Raymarine - Moderator - 09-26-18 11:01 AM

Hi alexandrerua

Welcome to the forum

The Bronze nut forms part of a recirculating ball leadscrew, the ball bearings are trapped inside the bronze nut, lightly greased and circulate through the nut, then pass through the bypass tube, which is the steel tube running diagonally along the bronze nut.

The [censored] (of which there are 44) are normally fed into the bronze nut and preloaded into the recirculating tube, which is then pressed into the bronze nut, I would add this is not a simple operation, special tools are required and generally customers end up having to replace the complete assembly.

regards
Derek