Sources in UK for a nylon bush/spacer for the rudder stock?

RichardS

RichardS

N/A
Joined
5 Nov 2009
Messages
29,212
Location
Home UK Midlands / Boat Croatia
Visit site
Whilst I'm on the hard I've taken the opportunity today to drop the starboard rudder. The port lower self-aligning bearing seized last Summer and we had to fix it in the slings before we could continue our cruise to northwards so I'm now making sure that the starboard one is OK.

The "good" news is that the grease on the rudder stock/self-aligning bearings has dried up or washed away completely so the stock would soon have imitated its port cousin. However, it wasn't completely seized so SWMBO and I were able to drop it. I will grease it tomorrow.

However, whilst I have got the nylon ( I guess it's nylon?) bush/spacer out I have taken a picture:

IMG_3967.JPG


As you can see, this one is in good condition but the identical one on the port rudder has almost split where the bolt goes through it. At the moment I have a couple of cable ties on it for security but I really need to replace it.

The size of the bush is OD 70mm, ID 40mm, Thickness 20mm. I have measured the rudder stock and that appears to be 39mm and hence the slightly larger spacer ID.

Is 39mm some kind of "standard" size for stainless steel rudder stocks? Just as a reality check that I've got my measurements correct.

Does anyone know where I can buy this kind of bush/spacer? Is it nylon? Even if it were solid I could drill the bolt holes myself which might make finding it a little easier.

Many thanks

Richard
 
Last year I had one made specially for my rudder. There was an advert on ebay; I gave the dimensions; he machined a delrin bush bearing and he send it by post week later; good job and well priced.
 
DinghyMan said:
As mentioned above delrin/acetal would be best - if you can't find anyone local and are happy with black acetal give me a shout and I'll turn a pair up for you
Click to expand...

CAPTAIN FANTASTIC said:
Last year I had one made specially for my rudder. There was an advert on ebay; I gave the dimensions; he machined a delrin bush bearing and he send it by post week later; good job and well priced.
Click to expand...

Many thanks Dinghy Man ..... that's very kind but I'd be happy to find a supplier on eBay as there are also some other "plastic" parts I would do well to replace.

Captain Fantastic ..... many thanks to you as well. Can you remember the eBay name of the supplier as I'd like to go somewhere "tried and tested" if possible.

Richard
 
You will still need the precise dimension to give to the machinist so that they can get the clearances right.
 
If it's already failed maybe the material (which looks like Polyacetal, Delrin is the dupont version) is not good enough?

I'd be interested to see how the spacer works as there are stronger lower friction materials than acetal but they are more rigid and can't be flexed, fully supported as a bearing sleeve they are better but can't be used as a mechanical support.
 
Never use Nylon for this type of application. It absorbs water and will eventually seize up on the shaft and in tis housing as it expands. This could be why the old ones have failed and split. When selecting plastic for ruidder bearings you need to ensure that it is a type that will not absorb water. I used PTFE for this, and although 8 years on its running fine, I have since been advised there are tougher plastics whicb will wear better.
 
I got mine from Trafalgar in Fareham, but they are specifically for a Westerly. They may well be of a standard size however as I doubt if Westerly went in for custom made bearings.
 
Wight Dawn said:
I got mine from Trafalgar in Fareham, but they are specifically for a Westerly. They may well be of a standard size however as I doubt if Westerly went in for custom made bearings.
Click to expand...

Doubt they are "standard" - one of the features of acetals is that they are easy to machine to custom size, so really no demand for standard sizes. Expect Westerly just had a local machinist run up a few at a time, and trafalgar would do the same as they probably have the drawings.
 
RichardS said:
Many thanks Dinghy Man ..... that's very kind but I'd be happy to find a supplier on eBay as there are also some other "plastic" parts I would do well to replace.

Captain Fantastic ..... many thanks to you as well. Can you remember the eBay name of the supplier as I'd like to go somewhere "tried and tested" if possible.

Richard
Click to expand...

His name is Robin. The email is: nemorobin@sky.com
 
39mm seems a bit of an odd size for a shaft. How accurate was your measurement? 1.5 inches is a standard imperial size of steel stock and equals 38.1mm. In metric steel, 40mm is a standard commercially available size in lots of different specifications including 316 stainless. 39mm may be available, but above 30mm standard stockholder available sizes tend to be in 5mm increments.
 
Norman_E said:
39mm seems a bit of an odd size for a shaft. How accurate was your measurement? 1.5 inches is a standard imperial size of steel stock and equals 38.1mm. In metric steel, 40mm is a standard commercially available size in lots of different specifications including 316 stainless. 39mm may be available, but above 30mm standard stockholder available sizes tend to be in 5mm increments.
Click to expand...

I thought 39mm seemed a bit odd but I measured it with a digital caliper at several places at right angles and it was always the same ..... 39.01 to 39.09.

I do remember now that when the yard engineer wanted to remove my lower bush last year after we had managed to get the shaft out he went to the workshop and came back with a "standard" length of rudder stock to act as a lever ..... but it didn't fit. He then went back and got another piece and that was too small. By now he was cursing something in Croatian which I couldn't understand but I'm now guessing was "What damn size is this rudder stock anyway?"

Richard
 
I looked into this a while back. Trafalgar will get them made to order but for my Typhoon they needed the old ones as a pattern as they didn't have drawings. The material of choice is UHMWPE (ultra high molecular weight poly-ethylene). Do not use nylon. It will swell as previously mentioned.
 
RichardS said:
Many thanks for your help. I'll email Robin to check if he is VersatileMarine2010.

Richard
Click to expand...

Just to round this thread off, Robin didn't reply to my enquiry but Peter Squire at Versatile Marine replied immediately. He was very helpful and suggested making the spacers in acetal/delrin and also making them a slightly tighter fit on the 39mm rudder stock. I though this was a good idea as it might be the deformation of the 40mm spacer when they are tightened up on the 39mm stock which causes them to split.

The new bushes below were £20 each + VAT and are exactly the same size as the spec I gave Peter apart from the 39.5mm ID rather than 40mm. Replies to emails were dealt with immediately by Peter and the bushes arrived in the post 3 days after I placed the order which, in my book, is excellent service for bespoke parts.

IMG_3999.JPG


Thanks to all who helped with this query. I'm delighted to have sourced these spacers I was expecting it to be a lot more troublesome. :)

Richard
 
RichardS said:
Just to round this thread off, Robin didn't reply to my enquiry but Peter Squire at Versatile Marine replied immediately. He was very helpful and suggested making the spacers in acetal/delrin and also making them a slightly tighter fit on the 39mm rudder stock. I though this was a good idea as it might be the deformation of the 40mm spacer when they are tightened up on the 39mm stock which causes them to split.

The new bushes below were £20 each + VAT and are exactly the same size as the spec I gave Peter apart from the 39.5mm ID rather than 40mm. Replies to emails were dealt with immediately by Peter and the bushes arrived in the post 3 days after I placed the order which, in my book, is excellent service for bespoke parts.

IMG_3999.JPG


Thanks to all who helped with this query. I'm delighted to have sourced these spacers I was expecting it to be a lot more troublesome. :)

Richard
Click to expand...

That's good news
 
You must log in or register to reply here.

Share this page

Top