Re: [bolger] planking material estimates
I built a MacGregor ~16' canoe several years ago in a boat building
class.
http://mkstocks.tripod.com/boats/macgregor_canoe/
The planks needed to be 16' long, so we made them from scarfed 8'
sections. However we did not scarf the sheets and then cut the
planks - instead the teacher instructed us to cut straight planks and
then scarf them together at an angle to eliminate a lot of waste that
would have resulted from the lack of nesting.
Hope that helps.
Mike
class.
http://mkstocks.tripod.com/boats/macgregor_canoe/
The planks needed to be 16' long, so we made them from scarfed 8'
sections. However we did not scarf the sheets and then cut the
planks - instead the teacher instructed us to cut straight planks and
then scarf them together at an angle to eliminate a lot of waste that
would have resulted from the lack of nesting.
Hope that helps.
Mike
On Feb 18, 2007, at 9:30 AM, derbyrm wrote:
> The strakes don't nest perfectly, so you need to allow for a lot of
> waste. In my case, my
> lofting was defective and I compensated by adding an inch or so
> along each edge of each strake. This was planed off later as the
> strake was coaxed onto the forms.
>
> Also, if you material is a couple of feet longer than the longest
> strake (which is longer than the boat) you can shift the next cut
> fore and aft to reduce the nesting loss.
>
> Roger (don't have a percentage, just a lot of scrap)
>derbyrm@...
>http://home.insightbb.com/~derbyrm
>
> ----- Original Message -----
> From: Derek Waters
> To:bolger@yahoogroups.com;boatdesign@yahoogroups.com
> Sent: Sunday, February 18, 2007 2:53 AM
> Subject: [bolger] planking material estimates
>
> Does anyone know of a useful rule of thumb for estimating the
> amount of
> planking stock required for glued ply lapstrake designs? I can
> 'guesstimate'
> surface area and lapping losses, but that's clearly not the whole
> story. At
> the very least a 'fudge factor' is needed.
>
> cheers
> Derek
>
> [Non-text portions of this message have been removed]
>
>
>
[Non-text portions of this message have been removed]
The strakes don't nest perfectly, so you need to allow for a lot of waste. In my case, my lofting was defective and I compensated by adding an inch or so along each edge of each strake. This was planed off later as the strake was coaxed onto the forms.
Also, if you material is a couple of feet longer than the longest strake (which is longer than the boat) you can shift the next cut fore and aft to reduce the nesting loss.
Roger (don't have a percentage, just a lot of scrap)
derbyrm@...
http://home.insightbb.com/~derbyrm
Also, if you material is a couple of feet longer than the longest strake (which is longer than the boat) you can shift the next cut fore and aft to reduce the nesting loss.
Roger (don't have a percentage, just a lot of scrap)
derbyrm@...
http://home.insightbb.com/~derbyrm
----- Original Message -----
From: Derek Waters
To:bolger@yahoogroups.com;boatdesign@yahoogroups.com
Sent: Sunday, February 18, 2007 2:53 AM
Subject: [bolger] planking material estimates
Does anyone know of a useful rule of thumb for estimating the amount of
planking stock required for glued ply lapstrake designs? I can 'guesstimate'
surface area and lapping losses, but that's clearly not the whole story. At
the very least a 'fudge factor' is needed.
cheers
Derek
[Non-text portions of this message have been removed]
All things wood I go +20% on length. If the end isn't split it may be
with a little drying and when bending having a little extra is always
handy. You can always find a use for the scrap even if it is only to
keep the shop warm or clamping blocks.
Jon
with a little drying and when bending having a little extra is always
handy. You can always find a use for the scrap even if it is only to
keep the shop warm or clamping blocks.
Jon
--- Inbolger@yahoogroups.com, "Derek Waters" <dgw@...> wrote:
>
> Does anyone know of a useful rule of thumb for estimating the
amount of
> planking stock required for glued ply lapstrake designs? I
can 'guesstimate'
> surface area and lapping losses, but that's clearly not the whole
story. At
> the very least a 'fudge factor' is needed.
>
> cheers
> Derek
>
Does anyone know of a useful rule of thumb for estimating the amount of
planking stock required for glued ply lapstrake designs? I can 'guesstimate'
surface area and lapping losses, but that's clearly not the whole story. At
the very least a 'fudge factor' is needed.
cheers
Derek
planking stock required for glued ply lapstrake designs? I can 'guesstimate'
surface area and lapping losses, but that's clearly not the whole story. At
the very least a 'fudge factor' is needed.
cheers
Derek