Light weight removable roof sections

[DHutch]

bit of a wierd question, but for my a-leval DT project im redesing and remaking the emilyannes coach roof, and im looking for ideas i could use and websites/companies i could get infomation and ideas from.

 

so if anyone had any ideas i would love to hear them?

 

 

danel

[John Orentas]

Daniel.

 

I understand you hope to study engineering next year.

 

Some applied geometry would give a design that would lift, tilt and slide to re-deploy the roof onto the cabin top though I suspect it already has that provision.

 

Design engineering encompasses many skills, not least to be able to articulate a precise requirement.

 

If you want to specify a re-design it would help if it were spelled correctly, please take these comments in the way that they were meant.

 

John Squeers

[DHutch]

yeah, sorry about the spelling (not a stong point)

 

anyway, at the moment the roof is just a sheet of 3mm ply on a woodern frame, which is light enought for for two people to easyly lift off onto the deck infront, then the sides and front are folded down, and the roof slide back to cover the folded down front window (so that it isnt in the way of the engine room roof hatch.

 

-also you can just fold down the front window, leving the roof on, which is good for very hot days (when you want the shade) and days which are warm, but raining.

 

-the problem is that the plywood is split and leaking, becuase its blown off twice since (once it went over the funnel onto the foredeck, the other it flowed about mile down stream)

 

-and the laminated beams are becoming delaminated.

 

_________________________________________________________________

 

Ideas that i have had include, leaving it roughtly as it is, but using polycabonate sheet, GRP or even a canvas skin on the top of a wooden or aluminum frame

 

- and maybe put rollers on the leading edge of the windows, and roof, so it could be lifted at the rear, rollered along the front of the windows, and then roll the fron edge of the roof along the deck

 

- or have it on arm with an "up and over" effect

 

 

daniel

[Gary Peacock]

Daniel

 

If you fancy something fancy we did one fabricated in steel mounted on four hydraulic rams. The roof had a sliding hatch that you could stand up through to steer when the roof was lowered.

 

 

 

 

Cheers

 

Gary

[DHutch]

If you fancy something fancy we did one fabricated in steel mounted on four hydraulic rams.

 

yeah, thats pritty cool, and the photos are good, thanks a lot - do you have a photo of it in the down position, because that whould be great, thanks

 

 

daniel

[Martin]

Keep the suggestions coming - we'll soon get this guy his A-Level between us!!!!!

[DHutch]

Keep the suggestions coming - we'll soon get this guy his A-Level between us!!!!!

 

I think thats a little bit unfair, im only asking, and im only trying to gather some research,

 

- part of the mark allocation is for "market research" ie what porducts are on the market, and why

 

thanks, daniel

[Gary Peacock]

Hi again Daniel.

 

I am still searching for a picture of the hydraulic roof in the down position.

 

But we are just starting on a removable aluminium roof so I will let you have some pictures of this soon.

 

 

Gary

[stuart]

If your pockets are deep, how about a carbon fibre roof section - really light and strong - just lots of cash!

[DHutch]

Hi again Daniel.

 

I am still searching for a picture of the hydraulic roof in the down position.

 

But we are just starting on a removable aluminium roof so I will let you have some pictures of this soon.

Gary

 

Thanks, dont worry if you cant find a picture in the down position, i dont want to be a nuisance

 

- is that aluminum roof going to have any lifting mechanism? or is it just designed to be lifted off by hand?

 

also stuart, i have though of carbon fibre, but i can see it geting broken, ie someone droping the funnel on it, or else treading on it when its off

- but thanks anyway

 

daniel

[John Orentas]

Daniel.

 

The weight will not be so important if you manage to design a suitable mechanism which can be collapsed without difficulty.

 

Don't try to do it mathematically. Draw the important parts of the boat to scale as big as you can. Draw in the roof 'up' and draw in the roof 'down'. Using bit's of cardboard and drawing pins design and make the struts which will make the transition from up to down.

 

Believe it or not that's how a prossesional designer would do it. In the first instance anyway.

 

John Squeers

[DHutch]

Daniel.

 

The weight will not be so important if you manage to design a suitable mechanism which can be collapsed without difficulty.

 

Don't try to do it mathematically.  Draw the important parts of the boat to scale as big as you can.  Draw in the roof 'up' and draw in the roof 'down'.  Using bit's of cardboard and drawing pins design and make the struts which will make the transition from up to down.

 

Believe it or not that's how a prossesional designer would do it.  In the first instance anyway.

 

John Squeers

 

yeah, thats what i plan to do

 

- should get started on it proper tommorrow

 

also gary i was looking on your website and came across some photos of one of a barge you have build with a clear coach roof, (as below)

And i was wondering if you could tell me a bit more about it?

 

thanks again, daniel

Edited December 14, 2004 by dhutch

[DHutch]

also do you know how often people noramal operate these roofs?

 

- like for instance that hydrolic roof, do they just lower it for bridges, or do they reguarly cruse with the roof in that down posision? - becuase most of the wheelhouses i've seen (mainly on your website) have much larger windows with much narrow glazing bars then our wheel house, which we basicaly only have up when its raining, and even then we often have the front windscreen down, becuase its very hard to navigate inside out wheel house!!

 

thanks again, danel

[Gary Peacock]

Sorry for the delay,

 

The clear acrylic wheelhouse is a bit of a Rolls Royce and not for people with shallow pockets.

They are custom made by Seaglaze Marine http://www.seaglaze.co.uk/

who manufacture very serious marine windows for the likes of the RNLI.

The side screens are fabricated from powder coated marine grade aluminium with stainless steel fittings. The acrylic roof is made in three sections the front and rear sections slide to allow sunroof style ventilation.

To lower the wheelhouse the three sections of roof lift off and the sides fold down, it's really a two man task but most manual wheelhouses are. The main advantage with this wheelhouse is it doesn't leak its not draughty and it doesn't get stuck.

 

The downside is the price your looking at around £12,000 for jut the bit that Seaglaze build!

 

A lot of our boats are residential and have a dinette in the wheelhouse so their owners tend to use them more like conservatory's!

They were designed to give the customers requested air draft so quite often they do not need to be taken down very often, but if the sides are left in the down position a simple canvas cover can be placed over the wheelhouse up stand to keep the weather out.

The hydraulic wheelhouse achieves the same by lowering itself onto the wheelhouse up stand.

 

I have got plenty of pictures of the Seaglaze wheelhouse if you would like some.

 

Cheers

 

 

Gary

[DHutch]

Yeah, i looks a bit posh. So its acrilic you say (not polycarb.) - i presume its been heated and formed into that shape? then the sections are they attached to a alumium frames, with the front rear one on rollers? how are they attached, are the just stuck on, or what?

 

- also its interesting to know that most people leave them on all the time, we basicaly always have it down, unless its actually raining, in which case we usally have the fron down. Becuase our windows are quite a bit smaller, with the glazing bar beeing thicker, and we have the door(s) at the back, so when the sides are up its like stearing with blinkers!! (we keep meaning to get the windows remade so the whole middle window slides backward, so whe can get our heads out too look down the boat) - some more photos of it would excellent though, Especially if there are some of the clear one in various states between on, siding and off.

 

- thanks again, daniel

[DHutch]

Well, ive been sketching/trying designs four hours (about 10-15)

 

- and i thin the best design is going to be a relatively simple design, where the roof is four wheels, to on the front of the windows, and two on the back of the roof. To lower the roff in uncliped, rolled along self suported, till it get halfway, then as it is rolled further forward the balence of the weight will be take by the people standing on the gunnel (or one on the roof), the front edge can the be lowered to deck leval, and it has to be lifted the last bit, as the rear edge comes off the front of the windows (which would be a bit diffecult with only one person, but if they went round to the back of the roof they could lift that down, alby it rubbing the front edge on the deck a bit)

 

Then, for materials/constuction, a frame that sides inside the windows, proberbaly made of wood, or maybe GRP or aluminum (although geting a nice curve inb the alu would be hard) - this "frame" would then have to be covered, eather with, plywood with a thin resin skin, or a peice of sheet GRP with some sort of stuff around the edge, or else make a former and made the whole thing and mould the curve/edges into the GRP, or i could use a sheet of clear, or white Polycarbonate/Acrylic although a sheet big enought to get a 5*6.6' peice from would be running well into £300/£400 (an 8mm 8*10' sheet or polycarbonate is nearly a grand!!)

 

-Or if i made it out of plywood, it could have a smaller polycarbonate "skylight" which copuld even be made to open, although all of this would add weight/build time/complication/cost to the roof.

-Or, if i was making it my self out of GRP, i could leave a area(s) without any pigmate, so that it would be tranlucent and let some light in when we have the rof up.

 

just a few ideas

- i'll try an get some picture of my design postd up when i get home (im at collage now)

 

 

daniel

Edited January 7, 2005 by dhutch

[Richard Bustens]

Hi Dan

A few years ago i saw a simular thing at Middlewich boat yard, but instead of removing the top it had a tank and pump , so instead of removing top to go through obstructions the tank was filled with water and the rear dropped and when clear if the obstruction the water was pumped out and up the boat went again.

 

Should be easer to get a waterproof seal by doing it that way.

[John Orentas]

Daniel.

 

Here's an idea for you to kick around.

 

Front of sliding roof; Running on rails along cabin top with an inclined plane to raise it to full height when fully back (horizontal bit of track with indentation to locate in position)

 

Rear of sliding roof; Supported on a strut, fulcrum at deck level and pivoted at rear of roof. Strut is vertical or leaning back a little at 'roof up' position.

 

Needs 'fold flat' windscreen.

[DHutch]

Hi Dan

A few years ago i saw a simular thing at Middlewich boat yard,  but instead of removing the top it had a tank and pump , so instead of removing top to go through obstructions the tank was filled with water and the rear dropped and when clear if the obstruction the water was pumped out and up the boat went again.

 

Should be easer to get a waterproof seal by doing it that way.

 

sorry, im not quite sure what you mean there?

[Richard Bustens]

Sorry Dan lets try again

Picture something like the one in post #12 but a fixed structure.

now that would not go under some of the bridges etc.

So in the back of the boat you put a big tank as big as you can get in. and a big pump,

When you want to go under a bridge that is too low pump the canal water into the tank and the rear goes down, when clear of bridge pump out the water back into the canal and up goes the rear again.

the boatyard that does them is the one at northwich next to the salt works. probably others as well.

[Trelawney]

Daniel.

 

Here's an idea for you to kick around.

 

Front of sliding roof;  Running on rails along cabin top with an inclined plane to raise it to full height when fully back (horizontal bit of track with indentation to locate in position)

 

Rear of sliding roof;  Supported on a strut, fulcrum at deck level and pivoted at rear of roof.  Strut is vertical or leaning back a little at 'roof up' position.

 

Needs 'fold flat' windscreen.

<{POST_SNAPBACK}>

 

 

Take a look at the majority of the Norfolk Broads cruisers for an example of this type of roof. The more modern boats have an electric motor to raise/lower the roof. The older boats have a hand crank.

 

Edit: Second thought. Maybe not.....the broads cruisers don't have doors along the sides of their cockpit/cabins. This might prove a bigger stumbling block.

Edited January 7, 2005 by Trelawney

[DHutch]

Maybe not.....the broads cruisers don't have doors along the sides of their cockpit/cabins.  This might prove a bigger stumbling block.

 

well, we dont have door on the sides, we have a pair of door on the back, be these come off (hinge pins out) before wee fold the sides

[DHutch]

Well, i had a long talk with my grandad (the "cleint")

 

And after much debate, mesurement, desction and workings (he is a mechanical engeiner as well as the clent) we've arrived at:

 

- 4mm plywood top, Hopefully one single peice, if we can find a supplier.

- that will be coverd with a THIN GRP skim (ie single sheet of high grade, thin weave glass cloth with the minimum required resin, white a white pigment)

- Wooden frame, with tapored beams and slimed down side rails (to lose the weight added my the GRP skim)

 

- this will then be designed to slid, proberble using a aluminium strip on the top of the windows, and teflon or simular on the under side of the roof, and maybe a roller, dependin how the teflon/alu goes in tests

- there will then be a pair of "ramps" which can attached from the front of the windows down to the deck when the roof has to be worked my one person.

 

 

daniel

Edited January 17, 2005 by dhutch

[DHutch]

or somthink like that

[ChrisPy]

Robbins Timber in Bristol can supply plywood in 10x5 ft sheets in some grades.