side windows on hull

I agree.

Very bad lewmar frames on all hatches.

The white coating is detaching everywhere.

Unbelievable, Lewmar should be a very experienced company !!

Painting or powder coating aluminium is not a reliable solution for aluminium finishing in a marine environment, especially if it’s used in a traffic location - feet, fenders or any form of rubbing or abrasion. The surface layer gets broken, even at a microscopic level, corrosion takes place lifting the edges of the surface finish and moisture then begins to track beneath it. The coating then traps the moisture and corrosion accelerates underneath the finish because the aluminium isn’t exposed to enough atmospheric oxygen to form a sufficient oxide barrier to prevent further corrosion. In the marine environment the best anti corrosion finish to use for aluminium is anodising (a controlled thickness of aluminium oxide that is sealed by heating to protect the aluminium underneath) but it needs to be at least 25 microns thick for marine use. Before sealing a dye can be used for different colours for the finished article.

The hatches that are used in powder coated ones will be the same base frames that lewmar will use for their anodised ones. As such I would expect a corroded frame, if not too badly compromised to be suitable for anodising once it has been properly grit blasted with a suitably fine abrasive. Anodising is expensive so prior to doing this you’d need to get prices, but it would allow you to have them done to a thicker coating and have a colour of your choice. Not an easy answer, but will probably give you the longest lasting solution.

Simon

this is just an example, every hatch is like this !

horrible and much corroded

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boomjack Members Profile Send Private Message Find Members Posts Add to Buddy List Captain Joined: 24 August 2014 Location: switzerland Status: Offline Points: 212	Post Options Post Reply Quote boomjack Report Post Thanks(0) Quote Reply Posted: 12 October 2024 at 20:18
	good to know and yes the quality of all the Lewmar aluminum hatches structure is scandalous!

marcopone Members Profile Send Private Message Find Members Posts Add to Buddy List Captain Joined: 24 April 2013 Location: Italy Status: Offline Points: 151	Post Options Post Reply Quote marcopone Report Post Thanks(0) Quote Reply Posted: 01 January 2025 at 19:18
	I agree. Very bad lewmar frames on all hatches. The white coating is detaching everywhere. Unbelievable, Lewmar should be a very experienced company !!

Matt1 Members Profile Send Private Message Find Members Posts Add to Buddy List Rear Admiral Joined: 10 March 2019 Location: Hamble, UK Status: Offline Points: 727	Post Options Post Reply Quote Matt1 Report Post Thanks(0) Quote Reply Posted: 02 January 2025 at 16:46
	The powder coating is the same issue with the white hatch frames from Lewmar. If it’s any consolation I saw a Hallberg Rassy with peeling white powder coating on hull windows so we aren’t alone :( I know the replacements are very expensive for the 418 so if / when mine fail I’ll likewise get them blast cleaned and painted
	Hanse 418 #64 EmBer. Hamble, UK

sgrhma2 Members Profile Send Private Message Find Members Posts Add to Buddy List Captain Joined: 20 November 2021 Location: Northern Irelan Status: Offline Points: 271	Post Options Post Reply Quote sgrhma2 Report Post Thanks(0) Quote Reply Posted: 02 January 2025 at 18:04
	Painting or powder coating aluminium is not a reliable solution for aluminium finishing in a marine environment, especially if it’s used in a traffic location - feet, fenders or any form of rubbing or abrasion. The surface layer gets broken, even at a microscopic level, corrosion takes place lifting the edges of the surface finish and moisture then begins to track beneath it. The coating then traps the moisture and corrosion accelerates underneath the finish because the aluminium isn’t exposed to enough atmospheric oxygen to form a sufficient oxide barrier to prevent further corrosion. In the marine environment the best anti corrosion finish to use for aluminium is anodising (a controlled thickness of aluminium oxide that is sealed by heating to protect the aluminium underneath) but it needs to be at least 25 microns thick for marine use. Before sealing a dye can be used for different colours for the finished article. The hatches that are used in powder coated ones will be the same base frames that lewmar will use for their anodised ones. As such I would expect a corroded frame, if not too badly compromised to be suitable for anodising once it has been properly grit blasted with a suitably fine abrasive. Anodising is expensive so prior to doing this you’d need to get prices, but it would allow you to have them done to a thicker coating and have a colour of your choice. Not an easy answer, but will probably give you the longest lasting solution. Simon

marcopone Members Profile Send Private Message Find Members Posts Add to Buddy List Captain Joined: 24 April 2013 Location: Italy Status: Offline Points: 151	Post Options Post Reply Quote marcopone Report Post Thanks(0) Quote Reply Posted: 02 January 2025 at 19:13
	Edited by marcopone - 02 January 2025 at 19:16

marcopone Members Profile Send Private Message Find Members Posts Add to Buddy List Captain Joined: 24 April 2013 Location: Italy Status: Offline Points: 151	Post Options Post Reply Quote marcopone Report Post Thanks(0) Quote Reply Posted: 02 January 2025 at 19:17
	this is just an example, every hatch is like this ! horrible and much corroded



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