Lewmar Hatch Crazed Finish Repair

[Kenomac]

We have a couple of overhead Lewmar hatch covers made of plexiglass or Lexan that have developed a crazed finish over the years. Is there a product that will remove the small scratches and restore the finish? Presently, it's like looking through a shattered window, but the hatch covers are working just fine... no leaks.

I have several 3M boat polishing products onboard, will these products along with some boat wax restore the finish?

Thanks for the help.

Ken

[Delancey]

Ken, short answer no. The Lewmar spec material is acrylic. Looks like you have Lewmar Ocean series, replacements should be available without the frame that mounts to the deck.

I have Lewmar Super Hatches which are out of production and a different size than the Ocean series so I replaced them myself, you can read below.

In the states a company called Select Plastics does replacement of just the lens itself for about the same cost as replacing with new but they make you wait six weeks. Meantime you have a hole in your deck that needs to be covered.

Hope this helps.

http://www.cruisersforum.com/forums/...nt-111539.html

Selectplastics | Selectplastics

[Charlie]

Ken there was a real good plastics shop in Caligari. Don't know about Olbia. They shut down in August though. Bring in the old and the next day they gave me a new one. In Europe I recommend using Silaflex product to seal. Make sure to use the Primer. Sorry dont remember the number but 291 comes to mind. When I did it I taped every edge with blue masking tape over hung the edges then cut with a razor knife. came out really nice. I think the price for one hatch and four portlights was Euro 50. Got it done in a couple hours while enjoying a beer.

[a64pilot]

The crazing is internal, it can't be polished out.
After you replace them, consider having some sunbrella covers made to keep the UV from ruining them when you not on the boat. My covers are insulated and keeping the sun out really helps the AC when we are in a Marina plugged into shore power, plus I hope will add life to the Acrylic

[sailnow2011]

I replaced mine with laminated safety glass. Came out crystal clear!

[cabo_sailor]

A lot of the time the crazing can be caused by using glass cleaner. That's a no no 😡

I had the same problem on my first boat. The only solution was to have a local plastics shop build me new ones. They did a terrific job and allowed me to change from clear to smoked, for all that FL sunshine.

Rich


Sent from my iPhone using Cruisers Sailing Forum

[travellerw]

I very much disagree with the posts here. The crazing is on the outside layer of the Acrylic and is no more than 1mm deep (yes it looks deeper).

If you are willing to do the work, you can bring them back to factory look. Its exactly like polishing and sanding gelcoat. Start with 220 grit WET and sand. Use water and light to determine when you have sanded low enough to remove the crazing (careful, 220 will remove material fast). Then move to 400, 600, 800, 1200, 1500 and polishing compound. What do you have to loose? This process is used in the airline industry all the time!

I had a C80 chartplotter that looked exactly like you hatch. I was able to polish all the crazing out and the screen looks like new now (although the anti-glare coating is gone).

[travellerw]

Unfortunately I don't have a better pic, or a before pic, but here is the plotter after polishing. The screen was almost unreadable before I polished it.

[Opie91]

Ken,
Try one of these kits. We use them on aircraft windows. Work great as long as you have some time to kill.

http://www.chiefaircraft.com/mm-kr70.html

Keep it wet all the time.

[Cheechako]

My Son in law owns an aircraft window repair facility. I forget what they use to polish windows but it works like a charm. Aircraft owners pay big bucks to get it done as the windows are super expensive. Cesium oxide?
But frankly, just replacing is a good option.

[Kenomac]

I'm going to try polishing one of them just like when I did the hull a couple of months ago. Sand paper then polishing compound, and see how it turns out. How can I harm them? They're already dead... Kinda like doing CPR on a dead guy... Really, I can't hurt them.

[Charlie]

How about some before and after photos Ken.

[Opie91]

Originally Posted by Kenomac

I'm going to try polishing one of them just like when I did the hull a couple of months ago. Sand paper then polishing compound, and see how it turns out. How can I harm them? They're already dead... Kinda like doing CPR on a dead guy... Really, I can't hurt them.

The kit above comes with all the paper and will last several hatches. Just clean the paper when your done. I have polished scratches out of gorilla glass with it.

[YachtOgler]

Please excuse me if this is an ignorant thought process, but aren't the lenses for hatch covers designed specifically with certain safety tolerances in mind?

In the unfortunate event that the boat capsizes, those lenses are what is keeping water out of the boat before it rights itself again. Even if the boat does not capsize, there are times when massive amounts of water are on the foredeck during heavy weather, yes?

So I am curious - am I overthinking this, or should people be very careful with what exact material and its associated tolerances they choose to replace factory lenses with? For instance, I am thinking it would not be a great idea to go to a random plastics shop and have new lenses made without the specifications required for replacement from the factory (material, thickness, and any other additional safety requirements).

I am also curious as to how many times you could de-haze your hatch lenses by wet sanding them down without affecting their strength.

How far off base am I here?

EDIT: Just read Delancey's writeup. Excellent and thank you.

[Charlie]

YO:

I think you are over thinking this. The tolerances are not that close. There are differences of opinions on what type of plastic you should use to replace the plastic but there are multiple products that fall within the safe category and they have their pluses and minuses. Also it is prudent on long bluewater cruises to have pieces of plywood stored on the boat which can be put over the hatches should the need arise.