Re: Chugger
OK, true enough but my drawing skills are sufficiently bad that, at
12:1, the margin for error is too much for me to give numbers and
have them accurate enough for my tastes. Also I said in the plan
views on the site is that it is Infininately variable from 48" to 0",
the only true way to get the length would be to mark out and actually
bend a piece of ply and measure the results. For the bottom curve,
Start with 3' back from the front edge, add the additional length
taken up by the curve, and draw a sweet curve. Realize that, once the
boat goes 3D, the curve will appear to become more abrupt, so the
lengthened curve on the flat panel should become closer to the plan
profile. (does that pile of verbiage make sense?)
Try this: Stretch the curve when flat, so that when it is bent, it
matches the drawing. For example: the side measurement of the curve
of the 18" wide bows would be 6-9" longer than the side measurement
of the Scow bow (48"), with a softer curve profile. Once bent to
shape the curve should (hopefully) match the design drawing with a
reasonable margin of error. Now, using 8' sheets of ply, this will
necessarily offset the joints somewhat, at the rear of the panel. To
get the boat to the right LOA will entail a little longer rear
panels, thus the reference to the additional material. If you use the
ply section designated for the foredeck, as the "curve testing
sheet", then you will eventually have the correct curves marked out
for it by default. (no wasted material there)!
Aannyy ways, that is why I think I'll put instructions to lay out,
thus avoiding having to figure out each and every length adjustment
from 0-24" in 1" increments (besides, it never comes out as planned,
does it?)
12:1, the margin for error is too much for me to give numbers and
have them accurate enough for my tastes. Also I said in the plan
views on the site is that it is Infininately variable from 48" to 0",
the only true way to get the length would be to mark out and actually
bend a piece of ply and measure the results. For the bottom curve,
Start with 3' back from the front edge, add the additional length
taken up by the curve, and draw a sweet curve. Realize that, once the
boat goes 3D, the curve will appear to become more abrupt, so the
lengthened curve on the flat panel should become closer to the plan
profile. (does that pile of verbiage make sense?)
Try this: Stretch the curve when flat, so that when it is bent, it
matches the drawing. For example: the side measurement of the curve
of the 18" wide bows would be 6-9" longer than the side measurement
of the Scow bow (48"), with a softer curve profile. Once bent to
shape the curve should (hopefully) match the design drawing with a
reasonable margin of error. Now, using 8' sheets of ply, this will
necessarily offset the joints somewhat, at the rear of the panel. To
get the boat to the right LOA will entail a little longer rear
panels, thus the reference to the additional material. If you use the
ply section designated for the foredeck, as the "curve testing
sheet", then you will eventually have the correct curves marked out
for it by default. (no wasted material there)!
Aannyy ways, that is why I think I'll put instructions to lay out,
thus avoiding having to figure out each and every length adjustment
from 0-24" in 1" increments (besides, it never comes out as planned,
does it?)
--- In bolger@y..., Mark Albanese <marka@o...> wrote:
> Actually, what's below is very backwards.
>
> Won't measuring the straight and level ( in profile ) deck
> edge around
> the plan view yield the sheet's true length?
> To get the chine curve elongated -just so- might take a
> dummy station for control.
> Mark
>
>
> >
> > You have the plan and profile curves of the bottom well
> > matched. What about going 'round the edge of it w/ scale,
> > if that's what it takes to get the length. Derive the true
length of the
> > foredeck edge the last. ( or again, what am I missing? )
> >
Actually, what's below is very backwards.
Won't measuring the straight and level ( in profile ) deck
edge around
the plan view yield the sheet's true length?
To get the chine curve elongated -just so- might take a
dummy station for control.
Mark
Won't measuring the straight and level ( in profile ) deck
edge around
the plan view yield the sheet's true length?
To get the chine curve elongated -just so- might take a
dummy station for control.
Mark
>
> You have the plan and profile curves of the bottom well
> matched. What about going 'round the edge of it w/ scale,
> if that's what it takes to get the length. Derive the true length of the
> foredeck edge the last. ( or again, what am I missing? )
>
Steve,
Not sure I understand what variables you mean. What I see
looks to fit the end of any sheet that's 4' wide.
I'd think the hardest part of narrower bows is bending
'round the plywood, yet that will make it stiffer.
You have the plan and profile curves of the bottom well
matched. What about going 'round the edge of it w/ scale, if
that's what it
takes to get the length. Derive the true length of the
foredeck edge the last. ( or again, what am I missing? )
If it's just a matter of the sheet usage, then a 6" shorter
boat won't be a problem.
There's nothing wrong with this boat as total scow, might
be even better sometimes. That is a great big piece of windage
though. And the smaller nose looks shippy. Complete lofting
and or a cardboard model might give
you yet another good idea.
Where do you find the time?
Mark
lewisboats wrote:
Not sure I understand what variables you mean. What I see
looks to fit the end of any sheet that's 4' wide.
I'd think the hardest part of narrower bows is bending
'round the plywood, yet that will make it stiffer.
You have the plan and profile curves of the bottom well
matched. What about going 'round the edge of it w/ scale, if
that's what it
takes to get the length. Derive the true length of the
foredeck edge the last. ( or again, what am I missing? )
If it's just a matter of the sheet usage, then a 6" shorter
boat won't be a problem.
There's nothing wrong with this boat as total scow, might
be even better sometimes. That is a great big piece of windage
though. And the smaller nose looks shippy. Complete lofting
and or a cardboard model might give
you yet another good idea.
Where do you find the time?
Mark
lewisboats wrote:
>
> Re: Chugger reference.
> Working on the scale drawings, having trouble with
> figuring out the
> lengths of the sides with anything other than the 4' wide
> bow. Too
> many variables on the curves if narrower than 48". The
> sides will
> have to be longer and the curves softer to achieve the
> same overall
> profile. I think that the plans will be for the square
> boat with
> instructions on how to loft the curves for the bow if a
> narrower bow
> is desired. I would think that if an 18" wide bow is
> desired, an
> additional 6-12" of material would be used to give the
> same profile.
> This would offset the butt joints somewhat, but that is
> not
> necessarily a bad thing. It might interfere with the side
> windows,
> but those could be relocated or narrowed. Plans will
> include same 3
> overhead lines for the bow as on the site. Sheets will be
> 8 1/2" X
> 14", Offsets for square boat only, Written build guide,
> and hopefully
> photos of build (downloaded only).