chromed outdrive

[Planetwarmer]

Has anyone ever tried this? Why are they all black (except for the Volvo guys) and not polished/cleared or chrome?

Any reason for this?

[Pismo]

or stainless steel....Weight, cost, I would guess. I think composite with stainless internals is the best idea. Needs to be worked out in the high power range tho. Pricey as well.

One guy I read about here or OSO has polished his and buff saturated it with many coats of WD-40 and said it worked well.

[WifeHatesMyDonzi]

or stainless steel....Weight, cost, I would guess. I think composite with stainless internals is the best idea. Needs to be worked out in the high power range tho. Pricey as well.

One guy I read about here or OSO has polished his and buff saturated it with many coats of WD-40 and said it worked well.

It was on here, I remember it also. It was during the winter and he said that he was bored, so he took a weekend out in his garage and buffed all of the paint off and then polished the metal. I can't remember the name of the thread.

[CHACHI]

Imco would polish you a shortie if you wanted it that way.

Ken

[gcarter]

I suppose you could use the chrome process they use for aluminum wheels, but if you scratched it, it would b e downhill from there.
Also, you could use clear powdercoat like they use on motorcycle engines. That seems to hold up quite well.

[gcarter]

You could also use a chrome paint w/a base/clear. But it would be hard to maintain.

[Pismo]

A hard anodized layer on top would be nice...

[RedDog]

My lower is satin - natural aluminum. The black paint was chipped and scratched. I had all of the paint removed by a restoration shop that had a bead or walnut shell blaster. Scotch Brite and WD-40 makes it look nice. I wouldn't leave it in the water long though due to corrosion concerns.

I shot it with clear coat urethane (sp?) but being an amateur, it didn't even last 1 outing.

[gcarter]

FWIW, mine isn't black.....or silver;

http://www.donzi.net/forums/attachment.php?attachmentid=51123&stc=1&d=1254066131

[mphatc]

All aluminum alloys are not ideally compatible with chrome plating when machined surfaces are required for part of the assembly.

Any coating that is an applied skin type . . chrome, powdercoat . . etc. needs to envelope the entire piece or it will ultimately separate and peel. When this happens corrosion progresses under the coating long before it is visible and damages the base metal .

Paint works when applied with the correct etching and corrosion preventative primers. Hardcoat anodizing will also work as it doesn't effect dimensions during the submersion into solution. Powdercoat and chrome build thickness and can not be used on assembly surfaces. Chrome is difficult if not impossible to mask for, and powdercoat leaves an exposed edge or seam at which corrsion will begin.

Polished aluminum will work well, IF you're able to clean it after every use, don't leave your boat in the water for extended periods . . and you desire to be anal . . . :cool:

I just refinished two Volvo 250 Drives with new Glasurit automotive paints, epoxy based, and went through a 3 step prep process. See images of the drives in the first post here: http://www.donzi.net/forums/showthread.php?t=59813

Mario L.

[mike o]

FWIW, mine isn't black.....or silver;

http://www.donzi.net/forums/attachment.php?attachmentid=51123&stc=1&d=1254066131MR. C , Ya stuff looks GREAT........ Even your hat on the wall's red........:kingme:

[Rootsy]

All aluminum alloys are not ideally compatible with chrome plating when machined surfaces are required for part of the assembly.
Any coating that is an applied skin type . . chrome, powdercoat . . etc. needs to envelope the entire piece or it will ultimately separate and peel. When this happens corrosion progresses under the coating long before it is visible and damages the base metal .
Paint works when applied with the correct etching and corrosion preventative primers. Hardcoat anodizing will also work as it doesn't effect dimensions during the submersion into solution. Powdercoat and chrome build thickness and can not be used on assembly surfaces. Chrome is difficult if not impossible to mask for, and powdercoat leaves an exposed edge or seam at which corrsion will begin.
Polished aluminum will work well, IF you're able to clean it after every use, don't leave your boat in the water for extended periods . . and you desire to be anal . . . :cool:
I just refinished two Volvo 250 Drives with new Glasurit automotive paints, epoxy based, and went through a 3 step prep process. See images of the drives in the first post here: http://www.donzi.net/forums/showthread.php?t=59813
Mario L.


Mario,

hardcoat anodizing does increase the component in size. If you wish for .001 film thickness the process builds inward .0005 as well as outward .0005..

Therefore if you have the coating stripped the resulting part will actually be smaller than before it was anodized...

Deal with this on a daily basis...

[joseph m. hahnl]

Mario,

hardcoat anodizing does increase the component in size. If you wish for .001 film thickness the process builds inward .0005 as well as outward .0005..

Therefore if you have the coating stripped the resulting part will actually be smaller than before it was anodized...

Deal with this on a daily basis...


Absolutely :yes:!!!! When machining parts the tolerance of the coating or plating is incorporated into the sizing of said part, so it is in compliance after finishing .NOTE* all dim apply after finish.

Gives me a chance to throw out the home brew:drunk:

:shades:http://www.focuser.com/atm/anodize/anodize.html (http://www.focuser.com/atm/anodize/anodize.html):shades:

[Planetwarmer]

If you polish a piece of Al and anodize it clear, will it still look polished or will it turn into a more satin finish?

[Rootsy]

It'll still look polished...

[Dr. David Fleming]

Polished lower units were standard on the outboard motors of the 1920-1940 era. I have many of these antique engines and the amount of corrosion on them can be quite substancial if they are not maintained regularly. The guys in those days would file them thinner and then buff them on the wheel - some ended up a lot more streamline. With the advanced hydrodynamic shapes today I would think you would screw up more than you would fix. However, when I look at my Bravo I, I realize that the factory dressed this casting on a belt sander and then polished it with a wheel before painting. It all looks like hand work. The painting is a godsend as is the Mercathode system - these things corrode even with that system and paint.

Some of the antique outboards made by Johnson in the 1920's had bronze lower units and towerhousings for salt water and are very heavy. ONe of my friends, Bob Zipps supplied a 1922 antique Johnson to the filmakers who did the Great Gatsby movie - If you look at the film you will see the daily maintenance needed as actor greases the lower unit.

By the way Johnson invented the sterndrive in the 1930's and could not develop it in the depression - surviving examples are in the Shipyard Museum in Thousand Islands, New York. Jim Winn who worked for Mercury rediscoverd the idea and developed it with Volvo in the 1970's. He added the universal joint driveshaft so we could have the whole trim thing. Karl K of Mercury told him it was all bulls... Later Carl would eat his words as Jim gave the idea to Volvo and Merc entered into a manufacturing agreement with Volvo to use it.

Dr. d