Lofting Floor

[chrisk]

I am going to try my first attempt at lofting a design, less then 20'x 6'. I have read a few books on lofting so I have the general idea. I don't want to loft on my cement garage floor, it's a bit cold right now.

Do I just go out and get a few 4x8 sheets of MDF and connect them together on the floor in my basement and start drawing? Some things I have read say to paint the floor white to draw on better.

Any comments or suggestions on how to put together a temporary lofting floor would be appreciated.

Thanks
Chris Kottaridis (chrisk@quietwind.net)

[jwaldin]

I'd make sure your floor is level first. If it isn't use 2X4s to make a level frame to put 1/2 marine ply on. By using plywood you can reuse it for something afterwards. A few sheets of MDF aren't much use in a boat. Screw down the ply with countersunk screws. Paint the panels with good quality proper enamel primer then low gloss white enamel. The low gloss with take a marker or pencil (I'd use indelable markers) better than high gloss. If you screw up you just paint over the mistake. Again, when you finish the lofting you've got some properly painted ply that can be used in a boat building project. Screw down a 1"X 2" strip along the bottom edge obviously making sure it's perfectly straight. Just use the factory edge of the ply as a guide.
Then construct a perfectly square wooden square 4 feet along the bottom and 4 feet high using best quality 3/4"Xfull 3" wood.
Make sure you got some good long battens, some bags with sand or shot to hold the battens down and you're set.

[Tar Devil]

Chris, another school of thought might be to use something like luan for your lofting. After lofting is complete, use the luan to make reusable patterns.

Later,

Phil

[B.Marks]

You could also loft the boat on the wall if there is enough space, helps on the knees and you can leave it up during construction so you have it as a constant reference. This won't help with the heat problem though.

[chrisk]

Thanks for the ideas. I don't think I'll be using a wall. Seems there are too many windows to get as much space as I need. Hadn't thought of the wall though. As it is I'll need to be moving a 60 gallon aquarium to find floor space. That is a non-trivial adventure, but I've done it before.

Sounds like it's worth painting it white to be able to see the lines better.

I was probably going to use batten holders as shown in the Gougeon Brothers book on page 118 to transfer the lines to the molds. Rather then draw the lines on the mold and have to "cut to a line", which I am not very good at, I planned on gluing or screwing the battens to 1/8" or 1/4" hardboard. Then I can take a router flush trim bit and make the batten and hardboard flush. I can then take some mold material and double-back tape it to the hardboard and just run the router around the edge. Kind of like making a mold for the mold as you suggest.

I did this on the CLC kayak I am finishing up. I layed out the points on some hardboard and then snugged the battens up against the nails and glued them to the hardboard. Then flush trimmed to the battens. I then took the 4mm ply for the real kayak and double backed taped two pieces to the hardboard templates and just ran a router flush trim bit around the whole thing. Wah-Lah. Two identical sides. Everything seemed to fit together quite nicely. If I want to build a second CLC kayak I still have the templates around to make the pieces. It worked out pretty well. I am hoping to have the same success in making some molds.

Us guys that don't have the steadiest of hands have to look for ways to compensate when trying to "cut to a line".

Chris Kottaridis (chrisk@quietwind.net)

[NormMessinger]

jwaldin describes a method for making a first class lofting floor. It would be a pleasure to work on same. However! I lofted Prairie Islander on luan painted matt white laid out on the carpet in the basement "family room." The sheets were butted together stapled to a backing strip, no glue. The backing strip compresses the carpet enough so the slight rise is not a factor. Don't remember what paint I used but next time it will be water based Kilz--cheap fast drying matt. Luan tends to dislike concentrated knee pressure but ones knees are almost always on the carpet anyway. After one no longer needs the loft the luan makes satisfactory patterns.

Fortuantly I only have a 10 gal aquariam and it was against the wall. Best wishes to ya.

--Norm

[jwaldin]

The ply can be used in lots of places where you are 'roughing' in the interior.
"Waste not want not".

[Ken Hutchins]

Look for oops paint usually sells for $2-4 per gallon, get any light color.

[Meerkat]

What design are you lofting? smile.gif

[Bob Perkins]

When I did my drawing, I used plain old latex primer (left overs from an interior paint job).

It dries really fast and takes pencil (and eraser) well..

Take care,
Bob

[Nicholas Carey]

spring for a roll of drafting mylar, say 48 inches wide. Lay that down on your loft floor/wall and do the lofting on it. Make sure you put registration marks on the different pieces so you can align them properly.

Voila! A lofting you can roll up and get out of the way, and pull out when you need it. The mylar's dimensionally stable, too, so measurements won't change on you as the humidity and temperature changes.

[chrisk]

I have the plans for the Bangor Packet and the veneer to make it. I've always wanted a sculling boat.

I also went to the library and have a copy of a sailing canoe from a Forest and Stream February 1900, (thanks to Dan Miller and his web site at dragonfly canoes for pointing me to a local university library). The canoe is called Foggy Dew. The article did not have a table of offsets but it did have some lines drawings. It's unclear that I am up to the task of taking those drawings and building a workable sailing canoe from it, but I sure intend to play around with it on the lofting floor.

At first though, I'll probably try lofting the MacGregor, which I also have plans for. That will allow me to test how good I am at lofting since those plans came with fullsize patterns that I can test my lofting patterns against.

I've been lurking for 2 or 3 years now, trying to glean experience and wisdom from you all and gathering books and plans. The kids are getting older, drivers license age, which is relieving me from chaffeur duties. I actually had at one time molds setup for a boat and was ready to plank when I had to take it down because we needed the space. I got it partly put back up to the same point when I had to take it down again. I just didn't really have the time to get it far enough along to make it anymore then a bunch of pieces. So, I've scaled back on the size of boat and maybe now I actually have enough time to put something together. So far the biggest hurdle to boat building has been time, or lack thereof. Maybe someday I may even get out of the Designs/Plans category and actually make a post on the Building/Repair category. Thats my goal, that by the end of the summer I have a valid reason to post a question on the Building/Repair category.

So, I am not exactly sure what I am going to build, if the lofting doesn't turn out to well I'll probably build the MacGregor using the full-size patterns. If I get a lot of confidence I may go for a sailing canoe based off of the Foggy Dew lines, it has a really neat steering setup and I have always wanted to try a sliding hiking seat. It also has bilge boards to keep the cockpit open which is a little bit unique in a canoe. If you can't tell I kind of like "gadgetry".

Any encouragement would be appreciated!

Chris Kottaridis (chrisk@quietwind.net)