Brass or Phenol?

[jmp]

Hi,
Have any forumites a view as to the best option for the outer surface of a cutless bearing,eg Brass or Phenolic. the application is a sailing yacht with GRP hull,s/s shaft running through a bronze "P" bracket at outer end with 1"x1-1/2"x4"cutless bearing.
Thanks in anticipation.

 

[Bodach na mara]

I have a similar set-up and have just done it in brass, which is what was supplied by the local engineers. I believe that the tufnol cased ones are mainly used in steel stern tubes and housings.

This was part of a small job that became a large one. The cutless bearing was showing excess play, so the housing was removed and a new bearing was ordered. The end of the stern tube came off with the housing, so that meant a new stern tube as well. When the bearing came, it would not fit the housing and was still a slack fit on the shaft so the shaft was condemned too.

 

[PCUK]

Phenolic every time. They are much easier to remove as they can be easily slit with a hacksaw once the shaft has been removed.. No corrosion and cheaper.

 

[vyv_cox]

I have used both and there is no appreciable difference between them. A point in favour of the phenolic ones, other than the good one in the post above, is that they tend to swell a little more after immersion for some time. The initial dry clearance is greater to allow for this. However, I find that they swell rather more than the clearance and can effectively take up some shaft wear.