I would like to remove the old hatch which leaks and install a new trapezoidal hatch with smoked Perspex.
The new ones are all significantly larger than the existing opening and I don't want to start hacking into the foredeck (I suspect the perimeter of the opening is structural).

One thought I had was to somehow (?) create some sort of base on the existing deck which would be outside existing opening. Then mount the hatch on that. I know looking from the top it would look a bit weird but does anyone have any suggestions. Boat is a Northshore 27.

This is what the sandwich looked like when I widened the hole for the centre hatch. Not sure if it would be same up the front.

Hi have you considered simply resealing the hatch to make it watertight, then if you are wanting light into the fwd area cut out an area within the nonskid pattern on the hatch and install perspex, lexan or whatever you feel is the appropriate material.
A cheaper alternative, less rooting around and more in keeping with the style of the boat.
Just my thoughts on the matter, cheers, Bob.

I agree with Bob. Cut a hole in the existing hatch and glue/bolt a tinted polycarbonate window to it.
Don't forget to cut the corners 'round' not square.

The hatch leaks because the seal does not line up with the lip on the opening. Easy to fix.

Best solution would be to mount a strong portlight in the existing hatch. However, anything that protrudes above the hatch may end up as a toe killer.

Keensailor might be on the best path with his ideas of installing a hatch on the deck. A chippie could do it in a few hours (It cost me a couple of hundred $$ to have a hatch installed in the deck over the main cabin)
MB also needs the front hatch resealed. I have now found that 1. seals are no longer available and 2. the old Lewmar hatch cannot be easily resealed because the glass has to come out to get the new seal in. I will have to put a new hatch in.
Keensailor might have the same trouble locating a seal to reseal the existing hatch. He might also have difficulty sealing a piece of clear into the existing hatch.

Yeah, come to think of it, what am I getting myself in for trying to retro fit a new hatch.....a lot of stuffing around.

I suspect I would need to reseal the screws on the hinge as well if I was going to keep existing hatch. Not that important to let light in, so might not put perspex window in.

Anyone know of any good seals?

Clark Rubber.

Hey it's just a rectangular section dense rubber seal, take a small section to someone who sells rubber, as suggested by sam, and cut and glue to suit.
The biggest issue is that the glue you use has to be strong and durable, I would probably use T-Rex or Simpsons.
Really easy, cheers, Bob.

I used existing hatch.... Traced the inside lip onto the hatch... Removed the hatch and cut it. Took it down to Vale plastics in brookvale.. He cut 10mm smoked acrylic and shaped it using the hatch. Bedded it down then male and female bolts.. Used hatch seal on the outer lip.. Works like a charm.. More light in the boat and looks great.. Will take a photo if you like.

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Yara said..
The hatch leaks because the seal does not line up with the lip on the opening. Easy to fix.

Best solution would be to mount a strong portlight in the existing hatch. However, anything that protrudes above the hatch may end up as a toe killer.

+1
The photos clearly show the foam/neoprene gasket doesn't line up with the hatch coaming.
Remove the old stuff properly & start again with new stuff, close the hatch, go inside & mark with a pencil where to place the new stuff. do it properly it shouldn't leak.

yeah, that would be great!
please message me
cheers

Sorry about the delay. As promised, here are the pictures of my forward hatch on my ns 27.. It's not quite finished 18 months on I still have a bag of stuff to finish it... A young family take all my spare time. Basically from memory I traced the inside lip onto the hatch then used a jigsaw with a fine metal blade to cut it out.. Took the hatch down to Vale plastics, he then cut, and shaped the acrylic 10mm sheet, then I stuck it on with silicon I think.. But plan was to bolt it on countersunk on the face.. But its still stuck well with just silicon.

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samsturdy said..

Clark Rubber.

One of the important jobs on MB was the forard hatch leak. The hatch isn't new but is still functional.
I eventually found a supplier of the seal in the US but they are expensive and he said the only way to fit one is to dismantle the entire hatch including the lens and refit it. He advised me not to bother for a hatch that old.
I looked around for hatches and it was looking like a minimum of $600 but more likely $800 for one the right size and quality. I am not in a position to install it so another $5-600 or so to put it in. The mounts are different so it will need a new frame to mount it on.
samsturdy here suggested Clark Rubber. I dropped into the Haberfield branch and they had a self adhesive hollow seal which looked like it would bend around the corners. I got $20 worth of it, about 2.5 metres.
I went up to MB this morning to fit a gearbox seal but it needs a special socket as the flange nut is oversized and a standard socket is too fat to fit in the opening. Bugger!
Not to waste the trip up I pulled the old hatch seal off, cleaned the seal mounting strip and put the Clarke rubber seal on. Threw multiple buckets of water over and at it. A leak from the handle. Pull the handles off and reseal them with marine silicone.
Threw numerous buckets of water at and over the hatch from all angles. One minor bit of seepage.
Early days yet but it is easy to carry a spare $20 seal if this one starts leaking.
samsturdy may have saved me a lot of money and hassle in suggesting Clark Rubber. Thanks mate.

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mjames said..
Sorry about the delay. As promised, here are the pictures of my forward hatch on my ns 27.. It's not quite finished 18 months on I still have a bag of stuff to finish it... A young family take all my spare time. Basically from memory I traced the inside lip onto the hatch then used a jigsaw with a fine metal blade to cut it out.. Took the hatch down to Vale plastics, he then cut, and shaped the acrylic 10mm sheet, then I stuck it on with silicon I think.. But plan was to bolt it on countersunk on the face.. But its still stuck well with just silicon.

very nice work mr james
i would welcome the extra light!

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MorningBird said..

samsturdy said..

Clark Rubber.

One of the important jobs on MB was the forard hatch leak. The hatch isn't new but is still functional.
I eventually found a supplier of the seal in the US but they are expensive and he said the only way to fit one is to dismantle the entire hatch including the lens and refit it. He advised me not to bother for a hatch that old.
I looked around for hatches and it was looking like a minimum of $600 but more likely $800 for one the right size and quality. I am not in a position to install it so another $5-600 or so to put it in. The mounts are different so it will need a new frame to mount it on.
samsturdy here suggested Clark Rubber. I dropped into the Haberfield branch and they had a self adhesive hollow seal which looked like it would bend around the corners. I got $20 worth of it, about 2.5 metres.
I went up to MB this morning to fit a gearbox seal but it needs a special socket as the flange nut is oversized and a standard socket is too fat to fit in the opening. Bugger!
Not to waste the trip up I pulled the old hatch seal off, cleaned the seal mounting strip and put the Clarke rubber seal on. Threw multiple buckets of water over and at it. A leak from the handle. Pull the handles off and reseal them with marine silicone.
Threw numerous buckets of water at and over the hatch from all angles. One minor bit of seepage.
Early days yet but it is easy to carry a spare $20 seal if this one starts leaking.
samsturdy may have saved me a lot of money and hassle in suggesting Clark Rubber. Thanks mate.

You're very welcome MB.....went looking for you last week but I couldn't see MB on it's mooring.

Select to expand quote

samsturdy said..

MorningBird said..

samsturdy said..

Clark Rubber.

One of the important jobs on MB was the forard hatch leak. The hatch isn't new but is still functional.
I eventually found a supplier of the seal in the US but they are expensive and he said the only way to fit one is to dismantle the entire hatch including the lens and refit it. He advised me not to bother for a hatch that old.
I looked around for hatches and it was looking like a minimum of $600 but more likely $800 for one the right size and quality. I am not in a position to install it so another $5-600 or so to put it in. The mounts are different so it will need a new frame to mount it on.
samsturdy here suggested Clark Rubber. I dropped into the Haberfield branch and they had a self adhesive hollow seal which looked like it would bend around the corners. I got $20 worth of it, about 2.5 metres.
I went up to MB this morning to fit a gearbox seal but it needs a special socket as the flange nut is oversized and a standard socket is too fat to fit in the opening. Bugger!
Not to waste the trip up I pulled the old hatch seal off, cleaned the seal mounting strip and put the Clarke rubber seal on. Threw multiple buckets of water over and at it. A leak from the handle. Pull the handles off and reseal them with marine silicone.
Threw numerous buckets of water at and over the hatch from all angles. One minor bit of seepage.
Early days yet but it is easy to carry a spare $20 seal if this one starts leaking.
samsturdy may have saved me a lot of money and hassle in suggesting Clark Rubber. Thanks mate.

You're very welcome MB.....went looking for you last week but I couldn't see MB on it's mooring.

Might have been taking her for a motor around Scotland Island. It is taking me some time to finish off a few jobs so I haven't sailed her since last November, except for a hour or so motor every couple of weeks. Having sold our house we are packing, looking for a new place etc, I have been doing a lot with the car club and I am working 3 days a week. Time for the boat is short! Which is why she is for sale to the right buyer, yachts must be used.

The last main one is the gearbox oil leak which I hope to either do or get done in the next couple of weeks. Making sure the oil level is not too full, as it just comes out, but adequate for proper lubrication before setting off allows me to use her but cleaning the oil out of the bilge is a pain.

I see some rain is forecast next week, that will help test the water tight integrity of the hatch seal.