How do you polsh a prop

rajjes

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My prop is not antifouled and after pressure washing it has a few barnacles marks otherwise its in good condition. How do I go about polishing it without being too agressive? An attempt with fine wet and dry did not remove the rough marks....
 
Wash with vinegar to remove last of limescale and then polish with a mild abrasive polish - e.g., Brasso / Solvol Autosol / Bar Keeper's Friend etc.
 
How does the prop stay in such good condition without resorting to the expensive concoctions sometimes recommended here????
 
Repeat of previous Feb 09 post

You get many opinions on here but decided that on balance polishing prop probably causes least growth.

I have tried Lanolin grease and it washes off very quickly.

Proof over what treatment is best eg High Polish v antifoul will be discovered next year.

If you do decide to polish prop I contacted Moleroda who are experts in equipment for metal polishing. They supplied a polishing mop and a sisal mop and a tapered mandrill with a female thread that fits on any large angle grinder (advised by Molerola than normal polishers are too slow). Compound was supplied as a solid green brick!

These mops are about 20mm thick and about 150 dia and you use them on their edge. I had to take the guard off the angle grinder as with mandrill the mop was spaced off by about 30mm. Apply edge of mop, spinning fast, onto brick and the green compound melts and "loads" mop. Apply to blades.

I used the course sisal one first then the softer one. All my blades and hub are now highly polished but can still see some manufacturing lines - assume when blades were ground to shape. No doubt these will reduce each year as blades get an annual polish.

Very satisfying to see face in blades and next year will see how good it works - after all GRP hulls are smooth and slippery yet they still get growth and need antifoul!.
 
someone suggested motorcycle chain oil which I'll try at the next lift out and let you know how I got on
 
that was either a biker who doesnt sail or a sailor who doesnt bike. Wont work. Comes off bike chains fairly quickly so I doubt it will make week 2 of prop use.

polished my prop this year using a foam head on an orbital rotary sander and some Farecla rubbing compound. You can now see the de-zincified bits /forums/images/graemlins/frown.gif polished to a mirror finish.
 
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Just had mine cleaned ready to electroplate with pure copper.Hopefully that will stop all the nasty s sticking.
I dont know if it will work or not but if you dont try you dont know.
 
There is a theoretical galvanic problem with this method. Graphite is a conductor that has its place in the galvanic series, so the prop could suffer an accelerated corrosion problem. A lot will depend on the precise composition of the prop, location of anodes, etc, so difficult to predict.

I have come across galvanic corrosion problems in the past where graphitic seals with stainless steel inter-layers came into contact with seawater but I don't have any experience with a prop. Probably not an issue, but you never know.....
 
I have tried antifouling. It just seems to come off in chunks very early in the season.
With some trepidation I tried a graphite based grate blacking compound. The good news was it didn't do any harm, ( I had shared Vic's concern abount some sort of galvanic corrosion, I guess the cell was not very efficient perhaps due to graphite being insulated from prop as a result of being held in suspension). The bad news was it washed off fairly quickly and allowed barnacles to form.
I tried polishing and have put the poor results down to not getting an adequate surface finish, so may try harder with this technique next time. Unfortunately will miss a couple of seasons due to overseas assignment. So will have to wait to see whether extra elbow grease produces better results.
 
You're right, I don't bike anymore. That's why I had a tin of chain lube left over and tried it on my prop. (sailing boat with twin bladed prop. 20hp auxillary engine)

It's worked well for the last few seasons with a spray or two during the season. But I try not to use the engine unless I have to, maybe that's got something to do with it.
 
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