neil1967
Well-Known Member
I know opinions vary, but could you not consider locking the propshaft when sailing, which would eliminate the problem in the first place?
Is there such a thing as electric conducting lubrication?
- Thread starter Otter
- Start date
lw395
Well-Known Member
In the old days, the connection was made to the shaft using carbon brushes as used in electric motors.
But I'm told that's not good with a stainless shaft, the stainless has an oxide layer that insulates, so the modern anode eliminator is designed to scrape.
I think I prefer a shaft anode. It puts the protection nearer where it's wanted.
But I'm told that's not good with a stainless shaft, the stainless has an oxide layer that insulates, so the modern anode eliminator is designed to scrape.
I think I prefer a shaft anode. It puts the protection nearer where it's wanted.
KellysEye
Well-Known Member
Vaseline, I used it to stop corrosion on the nuts and bolts on the winch electric motor. It doesn't conduct electricity.
Heckler
Well-Known Member
The "shade tree mechanics" in the third world where I worked most of my life actually used grease for battery connections etc. It worked remarkably well. Nothing wrong with Vaseline except it evaporates slowly, it doesnt dribble! There is a lot of "pissin" contests on here but some of us older contributors know what actually works in real life! Im including you in this category by the way!As Dipper says, it is effective at preventing moisture and corrosion so does provide long term connectivity but not because it's conductive as it's actually a good insulator. It can be used on battery terminals, as can vaseline, but that's because as the terminal is tightened up the grease is squeezed out from where the metals are in contact so current can flow.
In a situation where there is not a positive tight contact it's a lot more hit and miss as to whether an insulating lubricant will prevent good contact or allow it.
There are electrically conductive greases (not to be confused with thermally conductive greases which are common) but these are used in specialist applications and I have no experience of them. They are usually carbon based I believe and expensive. The obvious problem with these greases is that if they migrate from the original application site they can cause shorting and countless problems, especially in a moving or spinning application where the grease could be accidentally flung in all directions with potentially disasterous results.
Richard
Stu
ghostlymoron
Well-Known Member
As usual with discussions involving Contralube I'm now more confused as to what it really does. Afficionados claim it is simultaneously conductive and insulating - I think the latter.
A bit of a Schrödinger's cat!
A bit of a Schrödinger's cat!
RichardS
N/A
I think I've dropped down the rabbit hole. I've no idea what the point of all the web references is .... most on here know that I never use web references but only speak from personal experience 'cos most of the stuff on the web seems to be wrong.
What's confusing me is that you said "Contralube .... allows current to pass through it" and now you're saying "Here is a misinformed chap thinking Contralube conducts".
I assume that you're referring to yourself as the "misinformed chap" but I haven't read the links I'm afraid.
Richard
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Sailingsaves
Well-Known Member
I think I've dropped down the rabbit hole. I've no idea what the point of all the web references is .... most on here know that I never use web references but only speak from personal experience 'cos most of the stuff on the web seems to be wrong.
What's confusing me is that you said "Contralube .... allows current to pass through it" and now you're saying "Here is a misinformed chap thinking Contralube conducts".
I assume that you're referring to yourself as the "misinformed chap" but I haven't read the links I'm afraid.
Richard
You really are a piece of work. One day you are telling me I "won't be around for much longer", then next you are assuming I am the "misinformed" chap (without even reading the links)
The ybw links include posts by you, posts by the late and respected Nigelmercier that go into a little detail about the chemistry of contralube, and posts by Contralube and intelligent people that know the chemistry of Contralube.
Anyone who only speaks from personal experiences is not going to be as well informed as someone who learns from other sources.
I do note that you mostly give advice on the internet ("most of the stuff on the web seems to be wrong" ) and don't ask for much advice. Perhaps you know it all? Congrats.
I really must stop clicking on the bit that says: "view post"...
This message is hidden because RichardS is on your ignore list.
View Post
...that way I won't allow you to wind me up, but the devil in me enjoys how you twist words and love to argue - I still wonder if you were a barrister.
However, as of now with regard to posts by you I am most assuredly, OUT
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lw395
Well-Known Member
Contralube 770 is an insulator. It has a breakdown strength of 10kV according to the data sheet.
The list of suggested uses on the manufacturer's data sheet does not include actual moving parts such as a propshaft.
FWIW.
The list of suggested uses on the manufacturer's data sheet does not include actual moving parts such as a propshaft.
FWIW.
RichardS
N/A
I have absolutely no idea what this is all about.
Post #16 was a very simple observation. How did we get from there to "You really are a piece of work"?
Richard
Sailingsaves
Well-Known Member
Absolutely correct. As a well respected electronics expert your posts on such subjects should carry weight. (Even if some people believe that "most of the stuff on the web seems to be wrong").
Sailingsaves
Well-Known Member
To RichardS, if your post (that I choose not to see as you are on my ignore list) is directed at me, please save your time and energy.
You have wound me up on here and other forums with your twisting of words and subtle choosing of parts of a post to pounce upon, to the point where I do not wish to read anything you write.
If it was not directed at me, feel free to carry on.
I think the OP has enough info to sort his problem and wish him luck and fair winds this Summer.
You have wound me up on here and other forums with your twisting of words and subtle choosing of parts of a post to pounce upon, to the point where I do not wish to read anything you write.
If it was not directed at me, feel free to carry on.
I think the OP has enough info to sort his problem and wish him luck and fair winds this Summer.
RichardS
N/A
PaulRainbow
Well-Known Member
I'm clearly losing my mind.
Richard
You've only just noticed ?
Most of us have been aware of this for a very long time
Sandyman
Well-Known Member
Why not ? Do explain.
grumpy_o_g
Well-Known Member
Because it's a penetrant and will creep between the two surfaces making contact. You want metal to metal with nothing between. WD-40 is actually quite a good insulator but will only form a very thin film normally so the resistance remains low, which is why it works when you use it to clean up switches, etc.. When you are bonding two items you want the resistance as low as possible as even a small resistance over a long period of time can cause problems. The other issue with CW's actual use case is the the WD in WD-40 stands for Water Dispersant (which is why it's great for distributor caps). That's fine when you have somewhere for the water to be dispersed to but, if you use it on the shaft, it will very quickly simply wash away.
Some interesting facts about WD-40 - http://www.snopes.com/inboxer/household/wd-40.asp and the spec sheet for it http://www.wd40.co.uk/wp-content/uploads/2016/05/Multi-Use-Product-Aerosol.pdf
Otter
Well-Known Member
Thanks for all the replies but I'm a bit confused! This is what I've got:
The MG Duff electro eliminators work by making contact with the boat propeller shaft through brushes. This ensures that an electrical connection is made.
Whether you have a steel or GRP boat, an electro eliminator brush should be fitted to the shaft to provide the best protection to the stern gear.
The electro eliminator offers the most effective shaft bonding solution. By running directly onto the propeller shaft, the electro eliminator puts the anode on constant low resistance contact with the propeller shaft.
The copper graphite brushes provide a minimum of 2000 running hours under normal conditions. The electro eliminators also act to stop interference to electronic equipment, which may be caused by the rotating prop shaft.
I get that it has to clamp tightly but that also causes the squeaking - very loud squeaking! One solution is to just use a rubber band to lift up the clamp when we're on passage, a few hours without an anode won't hurt but that's a pain. I certainly don't want to loose any connectivity as it's a lovely new prop so a lubricant would have to conduct electricity. The shaft has no space for a shaft anode but could possibly just fit a collar anode, sadly my experience with collar anodes is that they fall off once they've been used up a bit.
The MG Duff electro eliminators work by making contact with the boat propeller shaft through brushes. This ensures that an electrical connection is made.
Whether you have a steel or GRP boat, an electro eliminator brush should be fitted to the shaft to provide the best protection to the stern gear.
The electro eliminator offers the most effective shaft bonding solution. By running directly onto the propeller shaft, the electro eliminator puts the anode on constant low resistance contact with the propeller shaft.
The copper graphite brushes provide a minimum of 2000 running hours under normal conditions. The electro eliminators also act to stop interference to electronic equipment, which may be caused by the rotating prop shaft.
I get that it has to clamp tightly but that also causes the squeaking - very loud squeaking! One solution is to just use a rubber band to lift up the clamp when we're on passage, a few hours without an anode won't hurt but that's a pain. I certainly don't want to loose any connectivity as it's a lovely new prop so a lubricant would have to conduct electricity. The shaft has no space for a shaft anode but could possibly just fit a collar anode, sadly my experience with collar anodes is that they fall off once they've been used up a bit.
Lon nan Gruagach
Well-Known Member
I saw a vacuum cleaner that had been serviced with WD40... The gout of green flame that it ejected was quite remarkable.
WD40 is extremely flammable, place it in an area where sparks are possible (IE near a slipping electrical connection) and fire will happen, albeit rather briefly.
Back to conductive grease:
Grease is a lubricant, if it does not form a layer between bearing surfaces it isnt a very good grease, is it? If that grease does not conduct then its a bit daft insulating your contacts. In the case of battery terminals, it is best to apply the protection after the contact is secured and such contact should be made to expel ant grease that has got onto the contacting surfaces. Also the reason for a lead terminal on a battery is to allow an extreme form of scraping contact where some material is removed to present clean (non oxidised) conductor.
By far the best slipping contact is carbon brush on copper slip ring.
lw395
Well-Known Member
Those things should run pretty quiet.
A few thoughts:
Are the pivots of the brush holders moving smoothly? Drop of oil here?
Is the shaft smooth? Polish with W+D paper
Is the mounting of the device firm?
Is the shaft out of round? Bent? Try moving the device to area with less deflection?
Try rubber mounting to damp the noise?
Fantasie 19
Well-Known Member
grumpy_o_g
Well-Known Member
It shouldn't have to clamp that tightly - it's the surface area in contact that determines the resistance, though clamping tightly means that you can be sure as much is in contact as possible. The whole point of brushes is that they are a soft material that wears down to conform to the shape of the other surface, giving a good contact without much pressure being required. It certainly shouldn't be making the shaft noticeably harder to rotate I'd say so perhaps that is your issue. Another option, if it's possible to get at and clean off the brushes and shaft afterwards, may be to use a little of a very gentle abrasive to help the brushes bed in as quickly as possible.