Fitting hatch on curved deck.

[Snowgoose-1]

Unfortunately the staggered piece of plywood disintegrated when I took the hatch out. The hatch is about 500mmx500mm . The fall is about 5mm to 10mm when I put a ruler edge down fore and aft.
I could make a plywood gasket again but have no idea how to take account of the curve. Any help would be very welcome.thank you.

 

[Tranona]

Cut a card template to follow the curve then transfer to a piece of solid hardwood wide enough to take the landing of the hatch. Epoxy to the deck. Makes sense to make an all round frame raising the hatch about 25mm at the crown of the curve above the deck.

 

[Seajet]

How about making a template from cardboard or thin plastic modelling sheets ?

A friend has a source of very affordable thick but file / carve- able plastic sheet which might well be good for this application.

500 X 500mm is a standard hatch size - a good source of new ones of various makes is Seateach chandlery at Emsworth, Hants.

If your callsign refers to an Anderson 22 or 26, please PM me, I can probably find you some help.

 

[PCUK]

Cover the frame with resin proof tape. Set the hatch up on the deck so that it is square and level with equal space beneath each side. Fasten lightly with a couple of screws. Use 'Bridger' filler ( Isopon P 40 for example) and press it under the frame all round to fill the void. When cured, remove frame and tidy up the new 'plinth' with epoxy filler. Sand smooth and paint.

 

[TQA]

Cover the frame with resin proof tape. Set the hatch up on the deck so that it is square and level with equal space beneath each side. Fasten lightly with a couple of screws. Use 'Bridger' filler ( Isopon P 40 for example) and press it under the frame all round to fill the void. When cured, remove frame and tidy up the new 'plinth' with epoxy filler. Sand smooth and paint.

+ 1

Parcel tape is a good release tape. I would make an internal and external frame to contain the filler and use tape on bits that will come in contact with the filler.

Watch out for the temptation to do the job in one go with large quantities of filler

 

[waynes world]

I made anew Hatch surround with Polyurethane foam and a little Fibre glassing and GRP filler to make good.

Here i made flat front windows fit the curve of the cabin.

Same as way as above.

 

[PaulRainbow]

Cut a card template to follow the curve then transfer to a piece of solid hardwood wide enough to take the landing of the hatch. Epoxy to the deck. Makes sense to make an all round frame raising the hatch about 25mm at the crown of the curve above the deck.

This is how one of my hatches has been fitted.

 

[MM5AHO]

I am in the process of re-seating my hatch on my Rival 32 just now. I used 2 x C shaped pieces of teak carved with a spokeshave to suit the curves of the cabin roof to leave a flat level flange of timber to screw the hatch flange to. I'll try and remember a picture this weekend.

 

[PCUK]

Nice work if you are a carpenter but the "Bridger" is easier and more durable being polyester resin and mat fibres the same as the rest of the boat.