Thread: lofting - then what?

It's helpful to actually have the lines on the floor in front of you, before jumping to conclusions about their usefulness. I use full size loftings all the time and pick up bevels, angles, dimensions, use them for making templates, etc.

Spring back can be accounted for in a bent frame situation, but as a rule they only move a very small amount, if at all. Laminated frames move very little, depending of the number of layers and several other factors. Steam bent frames can spring back a touch, but you can over bend them slightly which absorbs the spring back. Lastly, fasteners and/or glue will hold things where you want them.

Don't over think these things. What design are you contemplating building?

I am currently building a 16foot clinker Putt Putt,my first large timber boat. Having built glass and smaller timber boats in the past,stitch and glue,this is the first time I have had to do lofting. Water lines,buttock lines,bearding lines and rabbit lines. No wonder I took a line straight to the beer fridge!!. However after purchasing many books on boat building I eventually comprehended all the goobly gook. One thing that I have learnt the loft IS NOT the holy grail as you have found out. Springing battens to gain fair lines is all very well and good until you have to do the actual exercise. Sometimes it just doesn't work to the exact line shown on the loft. So what do you do?,You humour it in, so that it fairs onto the actual build. As Parr has pointed out adjustments sometimes have to be made regardless of the lofting. You will get the feel when you know it is right. Hard to explain.

The eye will fair better than a batten. With few exceptions I fair certain lines in 3D by eye, regardless of what the lofting or batten tells me. On most builds, I don't care what the sheer line is supposed to be, in regard to heights and widths, I pull the boat out into the open, stand 50' or more away and eyeball the thing. This is the line everyone's eye first catches, so it has to be right. Many times, once adjusted and compared to the lofting, you'll be "off" a good bit, but if the eye says it's right, the hell with the offsets. The stem profile is another place where I toss the offsets in favor of what my eye likes best. It's your boat, you have to live with it, so stand back (way back) and look her over, before getting married to a line.

Thanks Par. I am building this boat upside down only because I know my back will be all the better for it when I do the planking. I will worry about turning it over when the time comes. I totally agree with you in regards to eying off, as I have just done this in order to set out the planking. My main tool was the humble string line. Here are a few pictures of my progress so far.P9060034.jpgP9060031.jpgPA020080-001.jpg
The keel has now been rebated to take the garboard plank. Next to do is to rebate the station frames for ribands less,of course the thickness of the frames(ribs).
PA030082-001.jpg