Repainting a propeller

[Cast-Away]

I recently had my prop rebuilt. Soon after I put it in the water all of the paint came off. I later gave it 2 coats of primer and 2 coats of Mercury Phantom black paint. It to came off right away. Does anyone have any suggestions? I thought that I might bake each coat of primer and paint in the oven this time. Any suggestions would be appreciated. Thanks

 

[KCLOST]

Re: Repainting a propeller

If you're anywhere near Kansas City, I'll have it powder coated for you... Or even mail it to me.. I'm lucky enough to work for a Furniture Manufacturer and have access to a nice system...

 

[Cast-Away]

Re: Repainting a propeller

Thanks for the offer. I live just outside of Toronto, Canada. Do you think that powder coating it would do the trick?

 

[KCLOST]

Re: Repainting a propeller

I would think it would do better than almost anything... Just make sure you have all the old paint off... Good adhesion is the key and that won't happen unless it is completely clean and there is a good phosphate coating (part of the 5-stage cleaning process) prior to the powder application..<br />If you can live without the prop for a week or two, you can still send it to me and I'll take care of it for you.... We have 20 colors to chose from BTW.

 

[ndemge]

Re: Repainting a propeller

You just got an offer to get it powder coated... I would jump on it!<br /><br />My cousin in LA has a powder shop... couple years ago, camping on pismo beach... "powder coated donuts" for breakfast...the lil chocolate ones. <br /><br /> The women folk didn't get the joke.

 

[DJ]

Re: Repainting a propeller

Cast-Away,<br /><br />If the prop. is aluminum or an aluminum alloy; wash the prop thoroughly with a 50/50 mixture of vinegar and water before painting.<br /><br />The vinegar will slightly etch the aluminum giving the paint a surface it can hold onto. The same procedure holds true fo aluminum boats/ props./lower units and outdrives.

 

[Cast-Away]

Re: Repainting a propeller

I just went to the hardware store and found primer for aluminum. If I bake on the primer and paint, what temperature should I set the oven at?

 

[KCLOST]

Re: Repainting a propeller

I'm not sure about baking spray primer or paint...<br /><br />It may burn it more than anything unless it is specially formulated for that application...<br /><br />Powder coating is the only baking process I'm familiar with. We run our parts through a convection oven at 400 degrees for approx. 15-20 minutes. If we tried that with spray paint it would be burned to **** ...

 

[Solittle]

Re: Repainting a propeller

Best check the hub of the prop before you even think about any process that involves baking. Most props have a rubber hub and I would suspect that baking, at any temp, would destroy the integrity of the bond between the rubber hub and the prop.<br /><br />I assume that you would like to paint it for cosmetic reasons. Painting does nothing for the prop itself.

 

[sloopy]

Re: Repainting a propeller

the hub will POP out with preasure, when heat is applied. don't do it, the prop repair guys will charge you more for having to remove that sticky goo left in the prop and hub houseing!

 

[KCLOST]

Re: Repainting a propeller

Good point,<br /><br />Can't bake it unless it is only metal...

 

[andrewkafp]

Re: Repainting a propeller

Just my 2c..<br />I wet sanded my lower unit back to alloy.<br />Primed with "Etch" primer. Undercoated and finished with Merc Laquer.<br />One trip through shallow water where leg churned up some sand and all was gone from propeller tip and base of fin.<br />I say... don't bother painting, just sand it back to alloy and give it a clear laquer finish that gets a coat after each use...

 

[vidar]

Re: Repainting a propeller

Hi! use etch primer and then 4 layers of 2komp epoxy primer...that have worked wery well for me in salt water......

 

[crazy charlie]

Re: Repainting a propeller

Cast away,that is a great offer you got on powder coating.If you dont have a rubber hub then jump on it.If you do have a rubber hub then dont consider it.You must get the prop spotless clean.Sand it all over just before you either wipe it with acetone or vinegar.Avoid touching it after this is done.Set it in the sun and let it warm up ,spray 2 coats of zinc phosphate primer.Let it sit in the sun for as long as you can,it must stay warm.Put it back in the sun the next day and after it warms up spray it with either phantom black laquer or engine enamel.Leave it in the sun for as long as you can,the key is keeping it warm until it is dry completely.I would even go as far as putting it in an oven on very low.Dont use a heat gun to warm it after you paint it because it will heat the paint and not the metal.Be sure to spray the edges first and also last,this will prevent sheeting.Charlie

 

[wikelam]

Re: Repainting a propeller

I used to have a 68 sea king 40hp. the lower part, skeg, and propeller would always get the paint wore off. Sand from the river would do the trick. I would always head to Wally-World and get a $.97 can of gloss black paint. would use the whole can on them in numerous coats. this seems to last about a month or so. Since then have gotten a 74 evinrude 50 hp. doesn't work with this one though. but with the paint wore off the prop, it still runs perfect. just cosmetically challenged. so if you are worried about looks then paint it, otherwise no problem with a little paint worn off.

 

[Mark42]

Re: Repainting a propeller

I would suggest one more paint job before spending the $$ on powder coating.<br /><br />Get a can of spray expoy paint. Do the proper cleaning and prep, then paint with the epoxy paint, put in an oven set at 180* for about 5 min then remove and let cool. A super hard paint job for about $5.00<br /><br />Mark.

 

[crazy charlie]

Re: Repainting a propeller

Mark 42,I dont seem to find epoxy spray paint any more.Have you seen it anywhere in Jersey??Charlie

 

[walleyehed]

Re: Repainting a propeller

You're missing the problem at hand........Djohns19 gave the answer already.....The acid in the vinegar not only etches, it also cleans the pores. The next step would be to alodine the surface, and then it would be ready to paint......

 

[CTD]

Re: Repainting a propeller

Nothing will stay on very long. The longest lasting paint would be an epoxy primer with an epoxy topcoat. The epoxy stays a little flexible so dosn't chip off as easily. Unless you have it on hand from some other job a good auto type epoxy primer and hardner will cost $40-$80 per quart and about the same for the paint.It should hold up good on the outdrive and center of the prop but the outside edges hit every twig, leaf, beer can etc out there and eventually it gets worn off. If looks are important paint it with spray can black when you take the boat out each time. (My 2 cents)

 

[Mark42]

Re: Repainting a propeller

Hi Charlie,<br /><br />The brand I recall was Nybco. But I have not seen that for a few years. This past summer I bought some at a True Value hardware store, but I don't recall the brand.<br /><br />I know that some of the appliance paints are epoxy, but you have to read the fine print to get that info.<br /><br />A few years back I call Nybco and spoke to one of the chemical engineers and he suggested the oven trick to speed hardening and produce a higher gloss and harder finish than just air set.<br /><br />Good luck searching. <br /><br />Mark