WWA Info Exchange

For Woodworkers By Woodworkers
It is currently Thu Mar 28, 2024 1:18 pm

All times are UTC - 5 hours




Post new topic Reply to topic  [ 11 posts ] 
Author Message
 Post subject: A segmented bowl...
PostPosted: Mon May 24, 2010 2:17 am 
Offline
ModerDude/
User avatar

Joined: Tue Mar 26, 2002 1:01 am
Posts: 4125
Location: London, England
...is made up from rings of 32 segments. The segments have a cross section of ¾ x ¾ inch. Each segment will be 1inch long over its longest side. what is the largest bowl (external dimension) that could be turned using these rings?

Ralph :wink:

_________________
...Did I mention it rains here?

our other interests:
http://ralphsworkshop.blogspot.com/
http://notinmyfridge.blogspot.co.uk
https://my-meccano.blogspot.co.uk


Top
 Profile  
 
 Post subject:
PostPosted: Mon May 24, 2010 9:05 am 
Offline
Veteran
User avatar

Joined: Mon Jun 18, 2007 5:35 pm
Posts: 3620
Location: Hutchinson Ks
I'm going to say "five inches" max.
With 32 segments at 1" length (longest side) it figures out to be almost 5-1/8" circumference but, if you turn it to round and loose the corners of the segments it will reduce the diameter.
No, I'm not really that smart, I used a book called "Smoleys Four Combined Tables" to calcuate the diameter from my "assumed" circum. and guessed! :lol: :lol: :lol: :lol: :lol: :lol:

Rog

_________________
Dont badmouth no strangers, they just friends you aint met yet.

An ounce of responsibility is worth a pound of State and Federal laws.

I spent most of my money on woodworking
tools and beer, the rest I just wasted.


Top
 Profile  
 
 Post subject:
PostPosted: Mon May 24, 2010 12:54 pm 
Offline
ModerDude/
User avatar

Joined: Tue Mar 26, 2002 1:01 am
Posts: 4125
Location: London, England
Bump! :wink:

_________________
...Did I mention it rains here?

our other interests:
http://ralphsworkshop.blogspot.com/
http://notinmyfridge.blogspot.co.uk
https://my-meccano.blogspot.co.uk


Top
 Profile  
 
 Post subject:
PostPosted: Mon May 24, 2010 2:08 pm 
Offline
Veteran
User avatar

Joined: Thu Sep 16, 1999 12:01 am
Posts: 1935
Location: Forest, Ontario, Canada
A 32" circumference means a ~10.19" diameter. Taking the corners off while bringing down to round would reduce it a bit so I am going to say 10" diameter for the finished bowl.

Bob


Top
 Profile  
 
 Post subject:
PostPosted: Mon May 24, 2010 2:19 pm 
Offline
Veteran
User avatar

Joined: Wed Jul 17, 2002 12:01 am
Posts: 1067
Location: Boise, Idaho
Radius = 5.077 inches.

_________________
Winston (WWAIDAUX #2)


Top
 Profile  
 
 Post subject:
PostPosted: Mon May 24, 2010 4:03 pm 
Offline
Veteran
User avatar

Joined: Mon Apr 11, 2005 12:01 am
Posts: 4950
Location: Seattle, WA, USA
Hey Winston,

How did you come up with that? I've been playing with it, but I can't make it work without assuming a benchmark maximum of r=5.093.
32/π = 10.1859
r = 5.093

360/32 = 11.5º

Then I took the Cos of the bisected angle, assuming the middle of the chord to be the low spot.
11.5/2 = 5.75º

So, rCos 5.75 = 5.0674

The problem with my method is that the benchmark r of 5.093 is really and artifact.

Tom

_________________
"There is no path to peace, peace is the path."
Mohandas K. Ghandi
Image


Top
 Profile  
 
 Post subject:
PostPosted: Mon May 24, 2010 6:16 pm 
Offline
Veteran
User avatar

Joined: Wed Jul 17, 2002 12:01 am
Posts: 1067
Location: Boise, Idaho
I did it with a measurement on a CAD drawing.

Using straight math, I get the same answer:

Half-angle = 360 / 32 / 2 = 5.625º

0.5 / tan (5.625) = 5.0766....

_________________
Winston (WWAIDAUX #2)


Top
 Profile  
 
 Post subject:
PostPosted: Tue May 25, 2010 9:25 am 
Offline
Veteran
User avatar

Joined: Mon Apr 11, 2005 12:01 am
Posts: 4950
Location: Seattle, WA, USA
Thanks Winston,

I knew I was doing something wrong.

Tom

_________________
"There is no path to peace, peace is the path."
Mohandas K. Ghandi
Image


Top
 Profile  
 
 Post subject:
PostPosted: Tue May 25, 2010 4:19 pm 
Offline
Veteran
User avatar

Joined: Mon Jun 18, 2007 5:35 pm
Posts: 3620
Location: Hutchinson Ks
OOOPPPPSS!! :oops: :oops:
I obviously got the wrong answer!! I quoted radius instead of diameter. I know that pi is 3.141 so the diameter whould have been closer to 10 than 5 !!DOH!!!
Must have gotten on the wrong page in my Smoley's!! :oops: :oops:
Anyway Ralph, who won the coveted "Soggy Points"? And lets get on to the next puzzle.

Rog

_________________
Dont badmouth no strangers, they just friends you aint met yet.

An ounce of responsibility is worth a pound of State and Federal laws.

I spent most of my money on woodworking
tools and beer, the rest I just wasted.


Top
 Profile  
 
 Post subject:
PostPosted: Tue May 25, 2010 6:24 pm 
Offline
ModerDude/
User avatar

Joined: Tue Mar 26, 2002 1:01 am
Posts: 4125
Location: London, England
Looks to me as if Winston gets the soggy point today!

Ralph :wink:

_________________
...Did I mention it rains here?

our other interests:
http://ralphsworkshop.blogspot.com/
http://notinmyfridge.blogspot.co.uk
https://my-meccano.blogspot.co.uk


Top
 Profile  
 
 Post subject:
PostPosted: Wed May 26, 2010 8:26 am 
Offline
Veteran
User avatar

Joined: Fri May 12, 2006 9:37 pm
Posts: 5398
Location: Tucson, AZ
I think my head just exploded.....

and to think I always daydreamed in math class thinking "this stuff will NEVER come in handy in the practical world"

Lawrence


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 11 posts ] 

All times are UTC - 5 hours


Who is online

Users browsing this forum: No registered users and 21 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group