Rear Sliding Hatch (Trad Boats)

[mark99]

What is yours lined with under-side please?

[Jen-in-Wellies]

Plywood. It needs something over the bare steel to stop it dripping condensation. 

Jen

A semi trad, but they still have a sliding hatch. 

[mark99]

Ta. My rear hatch is off as the plywood 8mm has failed due to condensation I guess. I think it was non marine ply. At the mo being stripped and rust treated, to be undercoated then topcoated before lining.

 

Will post a few images tommorow.

 

Edited August 23, 2020 by mark99

[Richard T]

If you can get some insulation in before fitting the playwood do so. Something like cork sheet or a 10mm layer of closed cell foam. Ours is simply ply which has been varnished on both sides and edges.

[Tracy D'arth]

T&G parana pine on thin polystyrene.

[Jen-in-Wellies]

13 minutes ago, Richard T said:

If you can get some insulation in before fitting the playwood do so. Something like cork sheet or a 10mm layer of closed cell foam. Ours is simply ply which has been varnished on both sides and edges.

Good point. It occurred to me that I have no idea what, if anything, is between the steel and the ply on mine. All I can say is that it hasn't failed yet, whatever it is (or isn't!).

Jen

[Ray T]

1 hour ago, mark99 said:

What is yours lined with under-side please?

Wood, not sure what type though.

Could be marine ply.

 

No it wasn't off one of the kitchen cupboard doors. 

Edited August 23, 2020 by Ray T

[PeterF]

My previous boat came with nothing on it and I could only fit a 3mm layer on as the gap between the underside of the hatch and the top of the upstand on the roof was small so I put 3mm cork sheet on with no more nails then sealed it with varnish. Stopped the condensation, reduced the noise from rain and hail and was still in good condition when I sold it 14 years later.

 

Do not forget that if you use adhesive, it has to withstand the heat of the summer sun.

[blackrose]

The clearance on the underside steel of my sliding hatch was only about 5mm so although i managed to stick some cork tiles on the underside I didn't think that was enough insulation so instead I insulated the hatch from the outside with a sheet of 1" thick cellotex stuck on with Stixall and then I covered that with aluminium sheet and angle to make an external sliding hatch cover. The aluminium was stuck directly to the cellotex with Stixall. 

 

It's worked a treat. It's a widebeam so it was a heavy steel hatch to begin with and now it's even heavier. It still slides without a problem but it's not my main entry/exit so I'm only really using it in summer or when on the move.

 

I painted it with an etch primer, undercoats and top coats so looking at it you wouldn't know it's aluminium now.

 

 

[ditchcrawler]

I thought traditional ones were solid wood

[MoominPapa]

2 hours ago, Richard T said:

If you can get some insulation in before fitting the playwood do so. Something like cork sheet or a 10mm layer of closed cell foam. Ours is simply ply which has been varnished on both sides and edges.

Ours has 5mm ply stuck to silver "bubble wrap" insulation which is in turn stuck to the steel. Works well and is (so far) durable.

 

MP.

[LEO]

I made a new one for my rear slide last year. It's a traditional 'tapered' shape opening, 18mm ply, with 1mm steel covering externally. It's heavy so to make it slide more easily I rebated 1mm brass strips along the sliding areas, matches brass strips on roof runners. Internal finish, scumbled (by me). Works well.

 

Hope you are well.

 

M.

 

[Batavia]

Foam board, which is available in a range of thicknesses (mine was about 5 mm), doesn't rot and can be wiped clean.

 

Chris G

[mark99]

Thanks - good suggestions. I have 10mm to play with so should be able to sort something.

 

FAILED

 

 

 

 

 

 

 

 

Primed.

 

 

Edited August 24, 2020 by mark99

[mark99]

OK will be a composite bearing in mind I have limited clearance and have to mount hardwood strips for roof sliders.

 

2mm cork board on metal then 9mm marine ply on top of that. Then two hardwood strips 5mm for the sliders.

 

Will put up pictures when done.

[MoominPapa]

9 hours ago, MoominPapa said:

Ours has 5mm ply stuck to silver "bubble wrap" insulation which is in turn stuck to the steel. Works well and is (so far) durable.

 

MP.

I should point out that this slide runs on rollers, so there's no load on the lining. On a more traditional arrangement where the slide rests on the lining and the lining slides on brass strips on the roof upstands, it may not work as well.

 

MP

[blackrose]

3 hours ago, mark99 said:

Thanks - good suggestions. I have 10mm to play with so should be able to sort something.

 

 

As you have limited clearance then 5mm thick closed cell foam stuck on followed by some wood grain effect vinyl planks in your choice of colour might be the way to go. It's the stuff you can buy at b&q for about a tenner a pack and it's only about 3mm thick so thinner than faced ply. Stick it all on with Stixall.

[Athy]

Ours is just steel. No condensation problems in 14 years of ownership.

 

MG Boatfitting Services, the Boy Wonder who fitted 'Trojan' out, had great talent as a woodworker but no sense of time, so it may be that he meant to line the slide but never got round to it. Ditto the dog-boxes over the galley and the engine.