Sealing Hatches

[TiggerToo]

Can anyone think of the downside of sealing a Lewmar hatch to the deck using a layer of neoprene foam, instead of sealant like Arbomast?

 

[paulajayne]

Capillary attraction.

Water WILL get through.

 

[cobolt]

EPDM rubber tape would be OK, this is as many OEM's fit the Lewmar hatches.

 

[[3889]]

Capillary attraction.

Water WILL get through.

How? There is no moisture pathway through closed cell foam.
FWIW, I have used Scapa 3507 tape to seal deck fittings and this has remained watertight, so far, for several years.

 

[Yngmar]

The hatches and portlights on our boat are all sealed with some kind of foam (not sure if it's neoprene or something else) from factory, and none of them leak. Been there since the boat was built some 18 years ago. Couldn't re-use the foam though when I turned the forward hatch around. The foam seemed to work just as well and is definitely a lot lighter than the wad of butyl tape I replaced it with on that one hatch.

 

[rogerthebodger]

Can anyone think of the downside of sealing a Lewmar hatch to the deck using a layer of neoprene foam, instead of sealant like Arbomast?

I have also used foam to seal hatches and windows with not leaks.

I have also used foam to deal fittings and have no leaks on those either.

 

[TiggerToo]

I have also used foam to seal hatches and windows with not leaks.

I have also used foam to deal fittings and have no leaks on those either.

was the material "self-adhesive" or did you stick it on with something additional?

 

[Spyro]

The gap between the lens and the frame has to be filled, much easier to do with sealant as it will fill the space where as it might be difficult to do effectively with tape

 

[ditchcrawler]

When I replaced a hatch I used butyl tape 3mm thick, which comes in various widths. It was easy to fix as I peeled off the backing tape and stuck it to
the underside of the frame. I cut small pieces for the corners. It was much easier than using butyl from a gun as I usually manage to make a mess with any mastic from a gun.

 

[Spyro]

When I replaced a hatch I used butyl tape 3mm thick, which comes in various widths. It was easy to fix as I peeled off the backing tape and stuck it to
the underside of the frame. I cut small pieces for the corners. It was much easier than using butyl from a gun as I usually manage to make a mess with any mastic from a gun.

Masking tape everywhere you don't want the sealer helps a lot

 

[moomba]

When I replaced a hatch I used butyl tape 3mm thick, which comes in various widths. It was easy to fix as I peeled off the backing tape and stuck it to
the underside of the frame. I cut small pieces for the corners. It was much easier than using butyl from a gun as I usually manage to make a mess with any mastic from a gun.

+1 for butyl re bedded a front GOIOT hatch easy job no more leaks , easy to use , foam will deteriorate over time but have no idea how long , but would be easier to replace I imagine

 

[Concerto]

+1 for butyl rubber. It is a non setting seal, not an adhesive, so makes future removal a simple job.

I have used butyl rubber on stanchion bases and winches, both high load applications, and never had a leak. It adheres to both surfaces and it is best to fit any fitting and then retnsion it a few days later. Any that is forced out at the edge when tensioned can easily be trimmed away with a sharp knife.

If I had a choice beween a foam and butyl rubber, I would choose butyl rubber everytime.

 

[Spyro]

The gap between the lens and the frame has to be filled, much easier to do with sealant as it will fill the space where as it might be difficult to do effectively with tape

I must read the op more carefully

 

[rogerthebodger]

was the material "self-adhesive" or did you stick it on with something additional?

self-adhesive on one side