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[Pernicious Atavist]

okay, the skiff has its sides laid on the molds, temp transom is attached, stem is wired together to determine angles, etc.
now, my question is how do i determine that the sides mirror one-another? in other words, how, other than calibrated eyeball, do i determine if ech has the same bend at the same point?

[Bob Smalser]

I let a notch in the bottom of the upside-down molds attached to horses for a stringline. Notches big enuf so I can sight the line to make sure it's dead straight and dead center against marks in transom and stem.

When I need it, I stretch the line to stakes beyond the stem and transom marks and secure. Measurements taken with that as an index using with folding rule and torpedo level, or fixed square and torpedo level, depending on what I need.

For a boat with a huge sheer that interferes with a sighting, I could displace the string line to beneath the supports.

You could also do something similar with a batten, but it gets in the way and the stringline is always there loose on the horses when I need it.

[ 10-15-2003, 05:04 PM: Message edited by: Bob Smalser ]

[Banjo]

Yep ditto what Bob said,
Only thing I would add is that when on your own it's hard to hold the rule or tape steady against the line so I would use the straight timber batten aproach. Just put the tape against it's side and concentrate on getting the level plumb, of course you have to deduct the batten thickness on the other side or just hook your tape to the same edge you used before! smile.gif

[Pernicious Atavist]

i'm using the string and have measured at the broadest point, but one side looks flat, which leads me to believe there are parts that i can't deduce by eye that may be out of whack, too. i shimmed the flatter side and it looks better, but, you know....

[Bob Smalser]

Tack a batten in there between stem and mold dead on the string line and check your curves with a ticking stick.

A yardstick section with one end cut at a 60-degree angle...indexed against the far edge of the batten and the measurements recorded on each seam/lap/knuckle/riband for each side. Hold it against the batten with a trysquare for precision.

[ 10-15-2003, 08:06 PM: Message edited by: Bob Smalser ]

[Paul Scheuer]

In the Yankee Tender, the inner, cross-plank bottom goes on before the first plank. I was afraid that the chine log might not lay fair without the combination of plank and log. I made lots of measurements between the stations to the center line. I planned on temporary bracing if things were not symetrical. I found that I didn't need to do it, after many measurements.