Has anyone refinished a cast aluminum hatch?

[BAD ORCA]

I have Bomar cast aluminum hatches. I took the small one out and had it powder coated but it off-gassed severely (which apparently is an issue with cast aluminum) and has severe pinholes in the finish.

Im wondering if anyone has ever refinished one of these hatches other than just painting it? What process did you use?

They have a 'hammered' powder coat finish they think will work but i really dont like the look of that finish and would prefer smooth gloss black. Has anyone ever painted with a two part gloss black epoxy?

Anyone tried anodizing or having it sprayed with paint they use for cars? There is an autobody shop next to me that could paint it with automotive paint.

[s/v Jedi]

I have these and can’t getall the old powder coating off

For a small one, I got it to bare aluminum and then use a car alloy wheel polish from 3M and it held up great. Becomes dark grey colored.

[BAD ORCA]

Originally Posted by s/v Jedi

I have these and can’t getall the old powder coating off

For a small one, I got it to bare aluminum and then use a car alloy wheel polish from 3M and it held up great. Becomes dark grey colored.

Interesting, i might have them re-sand blast it and give that a try. I could always paint it i guess if i dont like the look.

[sailingunity]

Our boat came with bare cast aluminum "goiot" brand hatches. 49 years old and still looking great.

[s/v Jedi]

Originally Posted by BAD ORCA

Interesting, i might have them re-sand blast it and give that a try. I could always paint it i guess if i dont like the look.

Yes. You do see some irregularities from the casting process but they don’t bother me at all. If there is something that needs fixing then the original JB Weld works really well as it has aluminum as filler material.

[mlydon]

Read the process for your particular paint system….

For interlux

Grind/sand the entire surface to fresh, clean metal
Apply barrier coat within an hour
Apply epoxy primer, build up and sand smooth
Apply top coats

Some systems use an etching primer first, like alumiprep

I used this system on my mast 4 years ago - still mint.

I don’t see why it wouldn’t work on your hatches

Matt

[flee27]

I have the same Bomar cast hatches. And had the same problem with powder coating. My powder coater redid one 4 times and the final time came out OK. Acceptable but not great. The others I have striped, sanded then primed with an epoxy primer. The link below is for a product that I think is great for this. Then I base coat/clear coated with automotive paint. Look good and so far are durable.

https://www.southernpolyurethanes.com/primers

Good Luck.

Foster

[BAD ORCA]

Originally Posted by mlydon

Read the process for your particular paint system….

For interlux

Grind/sand the entire surface to fresh, clean metal
Apply barrier coat within an hour
Apply epoxy primer, build up and sand smooth
Apply top coats

Some systems use an etching primer first, like alumiprep

I used this system on my mast 4 years ago - still mint.

I don’t see why it wouldn’t work on your hatches

Matt

good info, thank you.

[BAD ORCA]

Originally Posted by flee27

I have the same Bomar cast hatches. And had the same problem with powder coating. My powder coater redid one 4 times and the final time came out OK. Acceptable but not great. The others I have striped, sanded then primed with an epoxy primer. The link below is for a product that I think is great for this. Then I base coat/clear coated with automotive paint. Look good and so far are durable.

https://www.southernpolyurethanes.com/primers

Good Luck.

Foster

Did you use a spray gun or brush?

[BAD ORCA]

Nevermind, my neighbors at the autobody shop are going to spray it for me.

[markxengineerin]

I have same hatches, it was an effort to get all the original coating off. Maybe 10 applications of stripper combined with lots of scraping.

For refinish, I polished them and applied "SharkHide" which is used on aluminum pontoon boats. It has only been a few months but looks good so far.

[BAD ORCA]

Originally Posted by markxengineerin

I have same hatches, it was an effort to get all the original coating off. Maybe 10 applications of stripper combined with lots of scraping.

For refinish, I polished them and applied "SharkHide" which is used on aluminum pontoon boats. It has only been a few months but looks good so far.

Good info, thank you.

The guys at the powder coating shop sandblasted them back to bare aluminum for me after the failed powder coat. Im not sure what type of media they used but they cleaned up really nicely. I noticed a lot of the imperfections from the casting process were smoothed out or removed.

The autobody shop next door is going to spray it gloss black for me and put a clearcoat on it with automotive paint, so hopefully its reasonably durable. This will be a test hatch and if it works well, maybe next season i'll clean up the two larger hatches and redo them. Not sure how it will hold up to the salt spray though.

[Franziska]

Originally Posted by BAD ORCA

Good info, thank you.



The guys at the powder coating shop sandblasted them back to bare aluminum for me after the failed powder coat. Im not sure what type of media they used but they cleaned up really nicely. I noticed a lot of the imperfections from the casting process were smoothed out or removed.



The autobody shop next door is going to spray it gloss black for me and put a clearcoat on it with automotive paint, so hopefully its reasonably durable. This will be a test hatch and if it works well, maybe next season i'll clean up the two larger hatches and redo them. Not sure how it will hold up to the salt spray though.

As its back to pure Aluminium, could you not have it anodized? Good anodizing last very long in masts and the like.

Btw. We did not want to sand the anodized finish on some new hatches, so normal spraying would not work, as that requires sanding.
We used black car rim spry film instead. It works, but is not quite robust as paint, but, you can renew it and you do not need to harm the anodized finish underneath.

[SVTatia]

I refinished the original Atkins & Hoyle hatches and ports on my previous boat and all the ports on my current one using the same process.
Sand and prime with 545 epoxy primer, sand, 2nd coat of 545 then 2 coats of your choice of polyurethane top coat. I used Awlgrip.
I did my ports 12 years ago, still looking new.

[BAD ORCA]

Originally Posted by Franziska

As its back to pure Aluminium, could you not have it anodized? Good anodizing last very long in masts and the like.

Btw. We did not want to sand the anodized finish on some new hatches, so normal spraying would not work, as that requires sanding.
We used black car rim spry film instead. It works, but is not quite robust as paint, but, you can renew it and you do not need to harm the anodized finish underneath.

I wanted them anodized originally but couldnt find anyone around me that could do it, and before they were sandbasted, the surfaces looked like crap from all the casting imperfections so i decided against it. Lots of tooling marks etc... Also, i think anodizing would have been beyond my budget. I set a max budget of around $200. The powder coating would have been $150 if it had worked. Not sure what anodizing would have been?