Advice Needed on Prepping and Painting an Alum. Boat

Patfromny

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Hey Guys,

I am getting ready to Paint my 77 16' Crestliner Aluminum boat and need tons of advice. I have never done any auto/boat body work and want to get it right.

The boat has been in my family since it was new. it sat for a few years in need of a new transom and we were going to scrap it but my and my brothers kids are almost at the age where they can take the boat out by themselves. I remember taking this boat out by myself for the first time like it was yesterday (30+yrs ago). It was my first real taste of freedom or independence. Being able to hop in the boat and blast down to the other end of the lake was fantastic. I decided to rebuild it for our kids (and maybe for me to fish a little too hehe). last year I replaced all the flotation, floors, transom, seat bottoms, console braces, etc. and went through the engine. We used it all last summer and it was like new inside. A complete success. I told the kids it was "Their" boat which they loved hearing. But now it's back home again this winter because the young owners want it painted and named in honor of my late father.

Anywho, that's the back story about my little boat project. the weather is just starting to cooperate hear on Long Island so I figured I should get going. I have read Yacht Dr.'s sticky on how to prep aluminum for paint but I need to know how to get to that point. specifically, I don't know what grit sand papers to use to prep the metal. there are many gouges down to the base coat of white and a few to the alum. The entire boat was painted white, then they painted over the sides with a dark blue. If anyone can tell me what grit to start with, what grit to finish with, and how many grit changes in between you would be helping me out tremendously. Also, can I used my electric palm/orbital sander for all, a few, or any of these sanding stages? I will buy a real da sander if need be or hand sand when recommended. I will need your advice at all stages of this project but figured I'd ask in stages as I progress.

I plan on using an HVLP or at least trying to. I don't mind doing a lot of prep. I know first hand the benefit of proper prep work on the finished product. I want any imperfections to be in the paint process due to my inexperience, not from cutting corners during prep. if any of you could chime in and lead my down the right path you would be helping me out a ton. I will have pics once I refigure out how to do so. One more sticky to read :)

Thanks in advance guys
 

Bondo

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Re: Advice Needed on Prepping and Painting an Alum. Boat

Ayuh,.... Welcome Aboard,... If the original paint is still solid, Wash it, sand it with 320grt. , prime it, sand it, 'n paint it,....

I Love usin' Rustoleum industrial enamel, with hardener,...

Any bare metal spots, need primin' with an etchin' primer,...
Don't worry 'bout the digs, dings, 'n jambs,... they add character to ole barges,... ;)
 

pckeen

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Re: Advice Needed on Prepping and Painting an Alum. Boat

Ditto on both the above. If the previous paint jobs were fairly good, then sand, prime, clean and repaint. If you need to strip, you are looking at a lot of work to get the stripping done. I think I had 20 or 30 hours into stripping my 16' Naden last year.
 

Patfromny

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Re: Advice Needed on Prepping and Painting an Alum. Boat

Thanks Bondo, Wog and PC.

I agree with you guys, I do not want to go nuts on a boat that I personally get to use 2 or 3 times a year and my nephew and nieces will certainly rescratch along their journey to boat mastery,but there are a lot or gouges along the sides that are through at least three layers of paint that I would like to smooth out. I'll post some pics in a few after I take them. Basically, I'll need to do some sanding I just don't know what grits to use or what tools to use. I'm definitely not looking to strip the whole boat. the original paint is in fine shape except for where we scratched it over the years. I just want to have a smoothish base to start from. I am leaving most small dents as character adders like you said Bondo but I want the thin, deep scratches to be smoother. sort of like what you do to smooth flaking or peeling paint on the outside of your house, you feather out the areas so the top coat looks good. Pics to follow, I have to go take them. Thanks again guys.
 

Watermann

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Re: Advice Needed on Prepping and Painting an Alum. Boat

I use 220 grit alum oxide sandpaper when doing the chip and gouge feathering. Then just wipe with acetone and shoot some rustoleum self etching primer on the bare alum. You can paint over the SE primer or put on a top coat of regular primer. As far as top coats go I do like using the tractor alkyd paint with the catalyst hardener.

2 coats of paint over the original and they're all bonded well, I've never had that sort of luck.
 

Patfromny

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Re: Advice Needed on Prepping and Painting an Alum. Boat

Thanks Watermann,

is 220 enough to cut the scratch down and not leave sanding marks? I would gladly go finer if it would create a smoother finish.
Here are some pics to show you guys what I'm talking about. The paint is in ok shape or is sound in most spots.


it's just these scratches or gouges that I want to feather out. The whole boat was painted white, then the blue was painted over that. most scratches seem/appear to be just to the white base color.





And I have a few holes from old covers as well


What I am looking for so I can paint (courtesy of the bumper moving and the boat rubbing the dock ladder all night)




I post a few more on next post
 

Patfromny

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Re: Advice Needed on Prepping and Painting an Alum. Boat

Here are some shots of the top side



Here the white is just wearing off and is chalky is some areas




Pardon the mess, I started working on this long forgotten project so I can sell it. They are side by side and I needed the room. The boat seems to be a great tote for all my junk I had piled on the conv.



Any advice to steer me the right way is needed and appreciated. Thanks again
 

Woodonglass

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Re: Advice Needed on Prepping and Painting an Alum. Boat

220 Wet Sanding and some high build primer on the deep scrathes and gouged areas. JB Weld or PC-11 to patch the holes. Final wipe down with Acetone and then prime with the Metal Primer.
 

Bondo

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Re: Advice Needed on Prepping and Painting an Alum. Boat

Thanks Watermann,

is 220 enough to cut the scratch down and not leave sanding marks? I would gladly go finer if it would create a smoother finish.
Here are some pics to show you guys what I'm talking about. The paint is in ok shape or is sound in most spots.


it's just these scratches or gouges that I want to feather out. The whole boat was painted white, then the blue was painted over that. most scratches seem/appear to be just to the white base color.

And I have a few holes from old covers as well

What I am looking for so I can paint (courtesy of the bumper moving and the boat rubbing the dock ladder all night)

I post a few more on next post

Ayuh,.... Yer gonna sand, 'n feather, hit the bare spots with etchin' primer, then primer the Whole thing, Right,..??

If so, don't go Nuts sandin' for a show car finish,...
Fair out the scratches abit, prime it, resand with 320gr. if ya want, 'n hit it with the enamel,...

For the holes ya got, pop in an aluminum closed end pop-rivet, sand, 'n paint,......
 

Porbeagle

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Re: Advice Needed on Prepping and Painting an Alum. Boat

All of the above advice is sound. I have had very good luck with WOODONGLASS's formula.
I'd go with his formula for a real pro job cheap.
Porbeagle
 

Patfromny

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Re: Advice Needed on Prepping and Painting an Alum. Boat

Thanks WOG, Bondo, and Por,

I do appreciate the advice from those who have,"been there, done that, got the iboats tee-shirt"I did try the 220 dry paper on a scratch and it does seem smooth enough. I'll give it the once over with 320 for my own piece of mind. You are right Bondo, I will have to continually remind myself to not go nuts as it's just gonna get ripped up again by the kids. I'm used to restoring cars and the value added from going the extra mile on just about everything you do. This will still be a 77 Crestliner when I'm done with it. Thanks again guys.

Next question...What do you guys think of hanging the boat from my garage ceiling to paint the bottom? My plan was to screw two 2x4 or 2x6's on each side of the boat to the sheetrocked ceiling putting a few deck screws through each joist. I would run the depth of the garage with the 2x's. The joists run across the garage bay so I could have these screws every 16" to spread the load. I would then put four Rings through the 2x's and into the joist and lift the boat with come along straps by the cleats. the boat weighs about 800 Lbs and I would take everything out and off the boat except for the cleats. It sounds just crazy enough for me to ask you guys whether I'm crazy or not. In my mind 800 pounds doesn't seem like a lot to hang from 12 joists but what do I know. Thanks again
 

gm280

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Re: Advice Needed on Prepping and Painting an Alum. Boat

Patfromny, If you are not satisfied with the smooth finish of 220 grit paper, first work the gouges and scratches with the bare metal primer and self etching and feather them out the best you can. Then I'd go over the entire boat with 220 grit. After that I'd spray a good quality primer on the entire boat (maybe an epoxy type primer) and then go with 400 grit wet/dry paper to get the smooth finish. After that its paint and you are finished. Priming of the entire boat is where you will use the finer paper if that is what you are looking for. It isn't necessary to go finer then that on the initial gouges and feathering the scratches. Save your arm until you work the total primer before the paint is applied.
 

Patfromny

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Re: Advice Needed on Prepping and Painting an Alum. Boat

Thanks gm280, makes sense, why do the fine stuff twice right? you just saved my arm and my time line. Wog said the same thing and it slipped right by me. Just like me to do stuff twice.
 

Bamaman1

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Re: Advice Needed on Prepping and Painting an Alum. Boat

I wouldn't lift the whole boat to paint the hull. Last time I did any heavy lifting, I drilled holes on each side of ceiling joists and looped 5/16" steel cables over them with cable clamps holding them in a circle. Then I used a come a long to do the lifting.

I would suggest you just pickup one side at a time--rolling the boat 1/2 on its side at a time. You want to have good supports for safety sake while you're under the boat.
 

SigSaurP229

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Re: Advice Needed on Prepping and Painting an Alum. Boat

Jack it up and back the trailer right out from under neath it. Or use and engine lift to hoist it with. Three guys can flip it over.

Use the rustoleum method, it works great fair it all out with 220 wash it all down with a 50/50 vinegar water mix don't touch it with bare hands after.

Touch bare spots with Se Primer.

Then go over all with high build.

This is my result from Rusto.

Rusto thinned at 15% with acetone mixed in 16 ounces batches add 1 teaspoon of Magic brand hardener.



Before you decide to HVLP it make sure your compressor is up to the task, it makes a huge difference. I have a 60 gallon putting down 13.6 CFM at 40psi.

I did my last one with an 18 gallon running like CFM at 40 and it just didn't have the guts.

It is not a show quality job but hey it is still a 1974 Starcraft right
 
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Patfromny

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Re: Advice Needed on Prepping and Painting an Alum. Boat

Thanks Bamaman, I need to do some work on the trailer bunks and trailer so I figured I'd use this method to lift the boat off the trailer. I would lower one side to sand and paint rather than get underneath. I thought this would be better than laying it on the floor and tipping to one side. or getting the trailer full of over spray. Maybe I could lower the boat onto some Harbor freight dollies for support and jack up one side to paint. I wouldn"t care if the dollies got painted.

Sigsauer, WOW, That came out beautiful. I would be happy if mine was 1/2 as nice. Looks like a new Crestliner. Thanks for the advice about compressor. I have a 25 gallon that I am concerned about. I was thinking of buying a second tank and piggy backing them together. I was told to also match the cfm of the gun to my compressor cfm. I was told this will utilize the small tank the best. Any thoughts?
 

gm280

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Re: Advice Needed on Prepping and Painting an Alum. Boat

Thanks Bamaman, I need to do some work on the trailer bunks and trailer so I figured I'd use this method to lift the boat off the trailer. I would lower one side to sand and paint rather than get underneath. I thought this would be better than laying it on the floor and tipping to one side. or getting the trailer full of over spray. Maybe I could lower the boat onto some Harbor freight dollies for support and jack up one side to paint. I wouldn"t care if the dollies got painted.

Sigsauer, WOW, That came out beautiful. I would be happy if mine was 1/2 as nice. Looks like a new Crestliner. Thanks for the advice about compressor. I have a 25 gallon that I am concerned about. I was thinking of buying a second tank and piggy backing them together. I was told to also match the cfm of the gun to my compressor cfm. I was told this will utilize the small tank the best. Any thoughts?

Patfromny, I actually sprayed a completely rebuilt outboard engine, a rebuilt trailer and trolling motor using a 4.5HP compressor and a HVLP gun without any issue with spraying what so ever. Most HVLP quality guns require 35 or 40 psi at the input to the gun yielding 10psi at the actual spray cap. So most any type compressor should work. That said, make equally sure you use a water trap at the gun as well... And if there is anyway to flip your hull over to spray the bottom, that would be the best. Then you could take all the time you need to finish it in a quality fashion. And yes you too can achieve that same shine and finish that Sig did as well, "IF" you're willing to take the time at the prep work. That IS where all the work is involved to get that type results...period!

Here is the title to my recently finished rebuilt trailer and sprayed finish: Bring a trailer back to life

So it is really possible, even for a first timer... :D
 

Woodonglass

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Re: Advice Needed on Prepping and Painting an Alum. Boat

The issue with using a small compressor is that when spraying larger surfaces and trying to maintain a wet edge the tank does not have enuf capacity to maintain the CFM needed. So since you need 35-40 it will fall below that and the pump will kick on and it will not be able to pump air fast enuf to keep up. You will have to stop spraying and let the tank build up air volume and pressure before you can start spryaing again and you Might lose your wet edge. This can cause shadow lines in you paint surface. Not saying this will happen but it is a possiblity. Also this constant cycling of the motor/pump is detrimental to the life of the compressor. I burned up my 2hp 20 gallon compressor because of this. I've since upgraded to a 60 gallon 3hp compressor. Just so you're aware;)
 
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Watermann

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Re: Advice Needed on Prepping and Painting an Alum. Boat

No matter what, just remember it's a home paint job done by someone who isn't a pro painter. All in all the goal is a decent looking, lasting paint job. It will have dust you missed, maybe a bug or two and lots of stuff your untrained eye didn't catch. Above all else, cameras from a reasonable distance make our home paint jobs look great!
 
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