Polished Chainplates

[odeapt]

Hi all,

I am currently in the process of replacing my chainplates, I have a Westsail 28 so my plates are mounted on the outside of the hull.

I spoke with a local rigger and he said he could make me new chainplates; his process was to have a shop cut them and he is polishing them himself.

He delivered 3 out of 6 yesterday and I don't know what to think about them.. I think they look really bad. You can still see the circular sanding marks on the plates. Also they still look a little grainy. One of there is some slight pitting at the top.

How important is it for them to have a perfectly smooth mirror finish? I can see my reflection in these but it certainly isn't perfect.

Also he is charging me $200 for them. I feel like that is a bit expensive. I have not yet paid him so I want to get the forums opinion before I accept these

[Sailmonkey]

Pics?

Imho, id request electro polishing on something like that.

[Suijin]

First of all you should ask your rigger what kind of stainless he used. He should have used 316. He may have used 304. I'm assuming you were charged $200 each. Since the cost is primarily labor it varies widely by specifics; size, shape, bends, number of holes drilled, and finally, degree of polishing. For example, the chainplates on some model Pearsons are going to run you $800 each.

Polishing definitely helps prevent surface rust, but the rust you really need to worry about is what develops where you can't see it, where it's sealed (and subsequently leaked), and moisture is trapped where there is no air circulation. With exterior plates, some tooth on the steel will actually help with the adhesion of bedding compounds.

Well polished stainless looks like a mirror; no grain, no swirl marks, nuttin'. You have to sand out the grain and then use progressively finer grits down to at least 800, then polish with a wheel and compound. Going from "I can see myself but there are marks and grain" to a mirror like finish is fairly time intensive, depending on your experience and the tools you have.

Sailmonkey is right; the best defense against rust is electro polishing, followed by expert chemical pickling. Polishing to a mirror surface is not too bad either. Expert metal fabricators will tell you that if polished properly the chemical pickling is not necessary and adds little to corrosion resistance.

[Terra Nova]

Have all the marks polished out. If your rigger is not equipped to do it find a metal polisher specialist.

[Wind River]

I had a guy polish a couple of stainless parts from my boat and they came back just as you described. I was not happy at all and paid him well below what he was asking for the time he put into it.

I took the same parts to another polisher and asked for a quote for the same work. I showed him what the other guy did and he asked "why so ugly?" He took the ugly part into his shop and 10 minutes later returned with a mirror finish and no marks or grain.

Don't settle.
It can be much better and you will wish you had them perfect.

[phorvati]

Its a labor intensive process. I dont think anyone will put the proper time to do it right. Well maybe not in the US. Even electropolishing leaves groves and marks. There is no substitute for putting in the labor required to get it mirror polished. Nobody seems to have the time. Thats why i'm doing it myself. I believe mirror finish is critical. Anything else will invite possibility for corrosion.
Here are some pics of my progress. From finish look, back to what they looked like after cutting stock 316L with water jet at the metal shop.

[G3stanton]

OK, one more step in my project to replace my 4 main sail chain plates. Where do I go to get them polished? They are SS 316 steel, cut in Michigan, so not very local. Thanks