CONTESSA 32 ASSOCIATION Homepage
Forum Home Forum Home > Technical Help > Engine, Gearbox, Stern Gear, etc
  New Posts New Posts RSS Feed: cutlass bearing
  FAQ FAQ  Forum Search   Calendar   Register Register  Login Login

cutlass bearing

 Post Reply Post Reply Page  <1234>
Author
Message
moongirl View Drop Down
CO32 Members
CO32 Members


Joined: 23 Aug 2009
Location: SOUTHSEA
Online Status: Offline
Posts: 232
Post Options Post Options   Quote moongirl Quote  Post ReplyReply Direct Link To This Post Topic: cutlass bearing
    Posted: 14 Apr 2012 at 7:12pm
Nick
I think the bronze tube is bonded in QED not a good idea to remove it!
Do you have a scanner so you can sketch your arrangement and e-mail to me to have a look. colinking@talktalkbusiness.net 
It seems that somebody might have pushed a bronze/'rubber' type cutlass bearing into the tube & its held in by the plate which is screwed into the hull. 
COLIN
Back to Top
NickVBaker View Drop Down
CO32 Members
CO32 Members


Joined: 31 Dec 2009
Location: Rowhedge, Essex
Online Status: Offline
Posts: 23
Post Options Post Options   Quote NickVBaker Quote  Post ReplyReply Direct Link To This Post Posted: 14 Apr 2012 at 8:01pm
Hello Colin

Will send some diagrams tomorrow. Thank you so much for your help. I don't think the plate is holding the bearing in, because i can quite clearly see the end of the brass tube holding the cutlass, surrounded by the bronze coloured flange. But I hope my diagrams will make it clearer.

Nick
Back to Top
GlennG View Drop Down
CO32 Members
CO32 Members


Joined: 18 Jul 2009
Location: Chatham - B29
Online Status: Offline
Posts: 51
Post Options Post Options   Quote GlennG Quote  Post ReplyReply Direct Link To This Post Posted: 15 Apr 2012 at 2:43pm
Does it look like this?   From CO548



The two screws were removed prior to the photo along with the filler between the skeg and flange.  The flange is solidly attached to the stern tube.
Back to Top
moongirl View Drop Down
CO32 Members
CO32 Members


Joined: 23 Aug 2009
Location: SOUTHSEA
Online Status: Offline
Posts: 232
Post Options Post Options   Quote moongirl Quote  Post ReplyReply Direct Link To This Post Posted: 15 Apr 2012 at 9:07pm
From the sketch e-mailed to me earlier by Nick it would seem that the arrangement is similar. Its the earlier fitting as per my drawing in the Technical Section ie bronze tube with the plate plus set screws. Nick's problem seems to be that someone in times gone past has drilled out part of the bronze tube and fitted a bronze/brass + neoprene cutlass bearing to replace the Tufnol bearing - as a result Nick is having problems removing the bearing as there is no step to drift out and nothing to get hold of with a pair of Mole Grips. I have suggested a Dremel cutter or one of those hacksaw blades held in a handle such that the blade sticks out allowing a cut to be made. Any other thoughts folks?
COLIN
Back to Top
waratah912 View Drop Down
CO32 Members
CO32 Members


Joined: 17 Dec 2010
Location: Lymington
Online Status: Offline
Posts: 98
Post Options Post Options   Quote waratah912 Quote  Post ReplyReply Direct Link To This Post Posted: 15 Apr 2012 at 9:51pm
Hmmmm.....head scratching time!!
If the shaft tube has been modified, then before trying to remove the exisiting bearing, I'd check to see if I can get a replacement. If so, ok go ahead and cut out the existing, though if it's been recessed into the shaft tube, sawing it out is going to be difficult without making cuts further up the tube, so back to a Dremmel type tool and grind slots at 18o degrees. 
If no replacement is available then consider a custom made tufnol bearing turned to either the id of the exsting brass housing of the cutlass bearing and just remove the neoprene, or to the od and remove the whole bearing, but in this case sounds like it would be only 2" long?
Back to Top
NickVBaker View Drop Down
CO32 Members
CO32 Members


Joined: 31 Dec 2009
Location: Rowhedge, Essex
Online Status: Offline
Posts: 23
Post Options Post Options   Quote NickVBaker Quote  Post ReplyReply Direct Link To This Post Posted: 16 Apr 2012 at 8:52am
Thank you for all your responses. 

Its not quite like GlenG's photo because there is no Tuffnol (or any other material) protruding aft of the rectangular flange attached to the stern tube. I.e it is flush and looking direct on to it you can see (from inside outwards) the neoprene insert, then the brass housing, and finally the bronze flange
Back to Top
waratah912 View Drop Down
CO32 Members
CO32 Members


Joined: 17 Dec 2010
Location: Lymington
Online Status: Offline
Posts: 98
Post Options Post Options   Quote waratah912 Quote  Post ReplyReply Direct Link To This Post Posted: 22 Apr 2012 at 9:25am
Off the wall thought - if you could make up a splined shaft to mate with the slots in the neoprene, you might be able to break the friction by rotating the bearing within the yube, once turning you may be able to "unscrew" it.
Back to Top
moongirl View Drop Down
CO32 Members
CO32 Members


Joined: 23 Aug 2009
Location: SOUTHSEA
Online Status: Offline
Posts: 232
Post Options Post Options   Quote moongirl Quote  Post ReplyReply Direct Link To This Post Posted: 22 Apr 2012 at 11:17am
Waratah's suggestion makes some sense but potentially a bit expensive if it doesn't work!
Of course you will still have the same problem in the future if you need to change the bearing again plus the bearing length will be less than normal. Perhaps the solution' once the old one is extracted, would be to
revert to a purpose turned Tufnol unit held by screws through the side of the skeg and fitted with an external step that could be gripped with Moles if it needed to be replaced. If there is any 'wobble' in the shaft then the Tufnol would wear rather quickly!

Regards                
COLIN
Back to Top
Simon Begley View Drop Down
CO32 Members
CO32 Members


Joined: 03 Nov 2010
Online Status: Offline
Posts: 28
Post Options Post Options   Quote Simon Begley Quote  Post ReplyReply Direct Link To This Post Posted: 22 Apr 2012 at 12:42pm
When we owned Milly Brown I removed the stern tube to get the cutlass bearing out. Once the two bolts were removed it slid out quite easily and I knocked the old Tufnol bearing out using a broom handle as a drift. Only the aft 50mm or so of the stern tube was machined internally, so to fit a brass and neoprene bearing (which was longer than the original Tufnol one) I machined the forward end down until it would fit inside the un-machined section of the stern tube.

We then did a summer in the Western Med, and motored back through the French canals and it was still ok when we got home!
Back to Top
NickVBaker View Drop Down
CO32 Members
CO32 Members


Joined: 31 Dec 2009
Location: Rowhedge, Essex
Online Status: Offline
Posts: 23
Post Options Post Options   Quote NickVBaker Quote  Post ReplyReply Direct Link To This Post Posted: 22 Apr 2012 at 2:24pm
Thank you, Simon for that info. 

I undid the two set-screws and tried to prize the flange away from the skeg, but it seemed very reluctant to part company. I got the impression that it was bonded in, but if so, why the set screws? 

What you say about the machining makes sense to me, because I had already concluded that the ID of the tube was considerably less than the 1 1\2 " which is the OD of the cutlass bearing. Mine has had a short cutlass bearing forced in (with no apparent way of pulling it out) - I guess to replace the tufnol bearing.

I'll get a bit more physical with the flange the next time.

Thanks
Back to Top
 Post Reply Post Reply Page  <1234>

Forum Jump Forum Permissions View Drop Down