Boat cover

[dutchman]

Si, Maybe you can help me out with this one…. (all others are welcome to advise too )
I want to build a tent to keep the water out of my boat while I am rebuilding it and am thinking of making one of 2” tubes 5mm wall thickness.
Haven’t made up my mind about the size and roofing material though… The shipyard doesn’t like plain plastic covers because of the flapping noise when the wind blows.
So here is my idea: cover half the boat in plastic and build a 5x3x3,5 metres (l x w x h) carport with those tubes and a wooden roof over the other half. Just to keep the water out of the part where I am working. I have to restore the whole deck and cockpit. Could build one twice the size to keep the whole thing dry, but would become rather large…. I was thinking roof only for simplicity.

Do you have any ideas or opinions on this??
Now that I think of it... working with epoxy could get difficult in a drafty/windy situation

 

[Drains]

Hey Dutchman.

Now when I built my boat I made the mistake of not investing in a good cover, so worked with the weather. Given the size of the boat (15m x 3m, x about 4m high for work purposes), it would have been a major investment, but worth it. We live and learn.

The way I would have done it would have been to build a poly-tunnel-like structure from curved ERW tube, with plastic sheeting stretched over as the cover, and suitable covering for the ends of the tunnel - either plastic or board, complete with doors.

To keep the shape of the structure I would weld smaller diameter tubes, as fixings, to the curves, , and slide tubes onto those to make a long, lengthways stiffener on the top and each side. Plastic over that, tight, keeps it strong and quiet.

The advantage of this design is:- lightweight - the structure is held together by the plastic, the steel can be thin, but is still strong. The plastic can be tensioned so it doesn't flap about. That way it won't tear, which is what ALWAYS happens to badly secured tarpaulin/sheeting. It is easy to make water/wind tight.

You could get the steel rolled to shape quite cheaply - it's a big radius - maybe the boatyard could do it? You'd also have to find decent plastic or sheeting, and work out how to tension it effectively. Polytunnel suppliers might be the place to look. I'm sure there are one or two of those in the Netherlands...

The idea might seem like a bit of hassle, but it will work, and be pack-upable, ands saleable after you've finished with it.

You could always look for a second-hand polytunnel and raise the height a little.

Cheers!

Si

ps, here's a cruddy picture, to help expain...

edit - What I did do at an early stage, before the boat had achieved full height, was make a pitched roof structure from scaffolding and lorry sheeting. It was very effective. What is most important is that the sheeting is tight, not only to keep it quiet, but to save it from flogging itself to death!

 

[dutchman]

Thanks Si,

So you really would go for a completely closed tent with doors huh…. I hoped to avoid having to build something completely closed like that, but you are the second person that advises a closed tent, so there probably is a big advantage to it.
I really like the smaller tube slide fixing principle you mention will certainly use that if I fabricate a tent myself. Might go for the raised poly-tunnel-tent design fully closed, or option nr 4 in my sketch and leave the sides open at first. Won’t do any welding in there and getting the plywood sheets in place would be a lot easier with open sides. Could always close them if it proves to be too cold I guess…

 

[Drains]

I wouldn't necessarily do a closed side. It really depends what you need to do, although a closed side structure may be stronger and less prone to wind damage, and obviously, wind chill. For epoxy work it's an advantage if you can keep the curing epoxy warm, or you could wait a long time for a cure. You could use a radiant heater if necessary, so a full cover wouldn't matter at all.

Bear in mind, my advice is based on what I'd do, if I were making a steel boat, not what i'd do to repair a fibreglass one.

Really, there's nothing wrong with any of your potential designs, including no1, but you need to make sure the cover is tight and can't flap (which is the yards' objection, after all), and that your construction is well enough fixed or weighted so the wind can't blow/suck it away.

 

[runnach]

Dutchman, don't know if this would do, so I took a couple of pics to give you an idea of what may be a quick fix for you? Basically it is a temperary carport, I think I paid around £150 total from Costco wholesale. I noticed newer type they now stock is now around £200 mark.

Length = 6 metre. Width = 3 metre. From ground to start of pitch roof = 2 metre. Ground to top of apex = 2.9 metre.

There are two front zipper doors to totaly enclosed but found them a pest, so took them off. You will note right hand side is now bolted to wall, as this was best setup for my requirements.

I know it is made from a plastic type material, that may not suit yard owners, but for the money, it was a very good buy, installed within a working day.

Maybe you can source similar around your area??

Cheers.........

 

[dutchman]

Thanks for the pics Runnach,

Such a carport thing would be very nice indeed, and what a bargain at 150 GBP!!
I think I’ll get me one of those carport covers in an appropriate size, (that sort of plastic would be ok since it doesn’t make the annoying flapping noise) and build my own frame to support it.
I will probably be spending a lot of time in it for the coming two or three years and like to stay warm, so closeable is better

 

[runnach]

What type of vessel you have Dutchman, sailing, cruiser, converted trawler....?????

Would love to view some pics if you have some available?

Cheers........

 

[Justme]

Just remember a few basic safety things.

Welding & grinding WILL make holes
Welding, painting & engine work WILL give of fumes

If you go fully enclose remember ventilation

Why reinvent the wheel?

There are plenty of large ex army type tents about that would do you.
Second hand poly tunnel frames & cover in a good tarp.
Plenty of cheap new party type marquees for sale.


Justme

 

[madkayaker]

welding and fumes will create bang!

 

[dutchman]

I don’t have many pics because I am usually too busy for taking pictures when at the boat yard. Will get you some next time.

The boat is a 27ft sailing vessel. GRP hull, wooden deck, cockpit, engine compartment and interior. According to the specs it ought to be reasonably fast, but no match to the ultra light modern racers. Most of the woodwork is invested by rot, so I intend to strip it all down to the bare hull and rebuild it. I bought it for silly money, so a bit of work was expected and I like doing it as well. It needs quite a bit of SS welding too. Stanchion bases, mast foot and some other parts need to be repaired or redesigned.


Just me, would it be a dumb thing to try and weld stainless in a small (yes really small) tool shed? The only ventilation I have is the door. Stainless is extra toxic isn’t it with all that nickel in the alloy.