Light weight wing for CAP 232
10-19-2002, 02:37 AM
#1
Senior Member
Thread Starter
My Feedback: (7)
Join Date: Sep 2002
Location: Mexico City, MEXICO
Posts: 441
Likes: 0
Received 0 Likes
on
0 Posts
Light weight wing for CAP 232
I'm building a CAP232 (LANIER) I'm interested on keeping weight as low as possible.
Among multiple weigh saving practices, I would select the balsa wood to be used.
I know that the "contest" balsa wood type is lighter however more expensive; therefore, more likely the manufacturer of my kit didn't include this type of wood.
a)I'd like to know how I can identify whether or not I have contest balsa grade already include in my kit.
b)Would you recommend contest balsa to sheet a foam wing of a 80 inches airplane?
Among multiple weigh saving practices, I would select the balsa wood to be used.
I know that the "contest" balsa wood type is lighter however more expensive; therefore, more likely the manufacturer of my kit didn't include this type of wood.
a)I'd like to know how I can identify whether or not I have contest balsa grade already include in my kit.
b)Would you recommend contest balsa to sheet a foam wing of a 80 inches airplane?
10-19-2002, 08:27 AM
#2
Member
My Feedback: (3)
Join Date: May 2002
Location: North East,
MD
Posts: 83
Likes: 0
Received 0 Likes
on
0 Posts
Wing sheeting and weight
Hi --
(long post - sorry)
Contest balsa should be fine for sheeting the wings of your 80" Cap. It WILL get hangar rashed a little easier than the heavier stuff though...
AS with any balsa, wood selection is important - I'll usually buy about twice what I need and use the best for sheeting... it's amazing how light and strong 3 or 4 ply balsa plywood is for bulkheads etc...
I've found that when sheeting wings a major factor in finished weight is the amount of epoxy I use - a serrated squeegee that allows just a thin film of glue on one surface is a great weight saver!
Best way I know of to ID the weight of balsa is to weigh it...
when I got serious about weight on a plane I found scales were essential - the link below shows a $3.95 postal scale that's fine for weighing individual balsa sheets.
http://www.greensmoke.net/scales.html
For heavier items ( like planes and components) find a digital scale that reads to 5 KG / 11lbs essential - available on ebay most of the time for about $45.00 .
This link will take you to a balsa weight chart -
http://www.stringwell.freeserve.co.uk/Balsa.htm
Sig's Contest Balsa is marked as such, and the last time I used any it was wonderful stuff.
Lone Star Balsa will send you 4-6# density balsa if you ask for it for a slight extra cost over their usual (very reasonable) prices. Others will do the same I 'm sure, but I've used Lone Star and found them to be good.
Hope this helps -
Rick
(long post - sorry)
Contest balsa should be fine for sheeting the wings of your 80" Cap. It WILL get hangar rashed a little easier than the heavier stuff though...
AS with any balsa, wood selection is important - I'll usually buy about twice what I need and use the best for sheeting... it's amazing how light and strong 3 or 4 ply balsa plywood is for bulkheads etc...
I've found that when sheeting wings a major factor in finished weight is the amount of epoxy I use - a serrated squeegee that allows just a thin film of glue on one surface is a great weight saver!
Best way I know of to ID the weight of balsa is to weigh it...
when I got serious about weight on a plane I found scales were essential - the link below shows a $3.95 postal scale that's fine for weighing individual balsa sheets.
http://www.greensmoke.net/scales.html
For heavier items ( like planes and components) find a digital scale that reads to 5 KG / 11lbs essential - available on ebay most of the time for about $45.00 .
This link will take you to a balsa weight chart -
http://www.stringwell.freeserve.co.uk/Balsa.htm
Sig's Contest Balsa is marked as such, and the last time I used any it was wonderful stuff.
Lone Star Balsa will send you 4-6# density balsa if you ask for it for a slight extra cost over their usual (very reasonable) prices. Others will do the same I 'm sure, but I've used Lone Star and found them to be good.
Hope this helps -
Rick
10-19-2002, 02:29 PM
#3
Senior Member
Thread Starter
My Feedback: (7)
Join Date: Sep 2002
Location: Mexico City, MEXICO
Posts: 441
Likes: 0
Received 0 Likes
on
0 Posts
Light weight wing for CAP 232
Thanks a lot for this information.
In addition I would like to mention that I successfully used a Polyurethane glue to sheet the foam wings of my Carden 27%. The glue in questions can be find in any Home Depot store under the commercial name PROBOND from Elmer's.
The glue is very strong and can be applied the same way as epoxy, I'm no sure about the density of this glue, however the advantage of this glue is that as it cures will try to fill any gap or air buble between the wood and the foam. Needs a lot of pressure. Once it cures seems to be as strong as epoxy.
So far I'v been flying this airplane and this wings have seemed to withstand wildest snap rolls so far.
In addition I would like to mention that I successfully used a Polyurethane glue to sheet the foam wings of my Carden 27%. The glue in questions can be find in any Home Depot store under the commercial name PROBOND from Elmer's.
The glue is very strong and can be applied the same way as epoxy, I'm no sure about the density of this glue, however the advantage of this glue is that as it cures will try to fill any gap or air buble between the wood and the foam. Needs a lot of pressure. Once it cures seems to be as strong as epoxy.
So far I'v been flying this airplane and this wings have seemed to withstand wildest snap rolls so far.
10-19-2002, 03:41 PM
#4
My Feedback: (40)
Join Date: Dec 2001
Location: Waynetown,
IN
Posts: 2,476
Likes: 0
Received 0 Likes
on
0 Posts
Light weight wing for CAP 232
I have found that in many kits while well engineered, they could have been engineered better. There are so many ways to lighten the airframe. You could simply drill holes in an area that is too bulky. Your wing ribs serve NO OTHER PURPOSE than to simply give the wing shape, so make sure you lighten the ribs up without taking so much out of them that they crumble. If you decide to glass the center section, USE CARBON FIBER instead.
Be creative and ask for the help of people in your area. Have them show you what they have done. Being able to see these sort of things helps you become more creative in the things that you do.
Jeff
Be creative and ask for the help of people in your area. Have them show you what they have done. Being able to see these sort of things helps you become more creative in the things that you do.
Jeff
10-19-2002, 03:59 PM
#5
Member
My Feedback: (3)
Join Date: May 2002
Location: North East,
MD
Posts: 83
Likes: 0
Received 0 Likes
on
0 Posts
kit design / lightening
Agree about kits not being engineered for max lightness -
they're probly engineered for economical production (ergo lots of light ply... and have you ever wonder why so many fuselages are 36" or 48" long ....? )
also engineered so that wood with a fairly wide range of density and quality will be acceptable.
Finally, so that a reasonably competent builder can miss a few glue joints and not have the thing collapse like a house of cards.
So....
a builder w/ a few kits under his belt can easily make a kit lighter - which always translates to 'fly better' - even with the stock outline.
Care and thought and incremental experimentation are wonderful things!
Enjoy!
Rick
they're probly engineered for economical production (ergo lots of light ply... and have you ever wonder why so many fuselages are 36" or 48" long ....? )
also engineered so that wood with a fairly wide range of density and quality will be acceptable.
Finally, so that a reasonably competent builder can miss a few glue joints and not have the thing collapse like a house of cards.
So....
a builder w/ a few kits under his belt can easily make a kit lighter - which always translates to 'fly better' - even with the stock outline.
Care and thought and incremental experimentation are wonderful things!
Enjoy!
Rick
