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View Full Version : Any Boost Glider Plans or Kits Using 1/4 Inch Thick Wings ?


BigRIJoe
01-04-2019, 02:53 PM
I have two sheets of pre-airfoiled balsa from SIG. They are each 1/4 inch thick. One is 4 inches wide and the other is 3 inches wide. I'd like to build a glider from plans using the balsa or make a copy of the wing from a kit using the pre-airfoiled balsa

ghrocketman
01-04-2019, 03:29 PM
Sounds wayyyyyyyy too heavy/thick for boost gliders.
Model aircraft use only.
Probably hard/dense balsa too, making it even worse.
That stuff is not for making wings; it is aileron stock for fun-fly type R/C aircraft.
Bet it has a fully symmetrical airfoil.

astronwolf
01-04-2019, 07:08 PM
I built one of these using 1/4" thick balsa for C rocket glider. It worked very well, and eventually it thermalled away.
https://www.nar.org/wp-content/uploads/2014/05/Nocturne-B-R-G-Vincent.pdf

For best performance Jeff's recommended balsa density should be used, but I wouldn't let that stop you if your balsa is a little denser.

BEC
01-04-2019, 07:57 PM
Sounds wayyyyyyyy too heavy/thick for boost gliders.
Model aircraft use only.
Probably hard/dense balsa too, making it even worse.
That stuff is not for making wings; it is aileron stock for fun-fly type R/C aircraft.
Bet it has a fully symmetrical airfoil.

Those 3 and 4 inch wide pre-airfoiled sheets from Sig are not aileron stock but have a simple flat-bottomed airfoil. They come in 3/16 and 1/4 inch thick x 3 x 36 inch pieces and 1/4 x 4 x 36 as well. Probably medium density (it's been years since I've actually seen one in person). I figured they were long gone, but it turns out they are still available: https://sigmfg.com/collections/sig-shaped-balsa/products/sigb111-balsa-3-16-x-3-x-36-air-foil-sheets?variant=12305562959950

Too heavy for boost gliders - maybe.

astronwolf
01-04-2019, 10:15 PM
Too heavy for boost gliders - maybe.
My guess too... but you never know.

Ez2cDave
02-25-2019, 07:18 PM
I have two sheets of pre-airfoiled balsa from SIG. They are each 1/4 inch thick. One is 4 inches wide and the other is 3 inches wide. I'd like to build a glider from plans using the balsa or make a copy of the wing from a kit using the pre-airfoiled balsa

Here is one . . . The "EASY RIDER IV" , from March, 1975.

1/4" Balsa . . . For D12 motors !

Dave F.

ghrocketman
02-25-2019, 08:55 PM
Regarding that above design, back during that era it was common for hobby shops to carry 4 and even 5 grades of Balsa- Soft, Medium, Hard, C-grain, and Contest (lightest).
Good luck with that nowadays...most all is too dense/hard in 1/4" thickness at hobby shops.
One would have to order specialty balsa thru a supplier or it most likely would glide like a manhole cover.

astronwolf
02-25-2019, 09:17 PM
Good luck with that nowadays...most all is too dense/hard in 1/4" thickness at hobby shops.
One would have to order specialty balsa thru a supplier or it most likely would glide like a manhole cover.
:rolleyes: Negative Nelly hard at work...

When I want to stock up on balsa, I take my digital scale and sweep through all the local crafts stores and I usually come away with some choice pieces of balsa. You can find some pretty good wood this way. Or you can order from SIG.

Ez2cDave
02-25-2019, 09:36 PM
http://www.modelaviation.com/balsa

http://www.modelaviation.com/images/article/balsa-density.pdf

https://sigmfg.com/collections/specialty-balsa

https://sigmfg.com/products/sigb454-1-32-x-3-x-36-contest-wood

http://www.specializedbalsa.com/products/balsa_sheets.php

https://www.nationalbalsa.com/Aero_Light_Balsa_p/116348ct.htm

Jerry Irvine
02-26-2019, 05:44 AM
Okay I will do something radical and post an on-topic response.

http://v-serv.com/crp/CRm/1-82/CRm.1-82.19.w.jpg

http://v-serv.com/crp/CRm/7-81/CRm.7-81.17.w.jpg

stefanj
02-26-2019, 09:23 AM
Alternative Use:

Cut the sheets into paralleleogram shaped fins, with a generous tab.

Mount on a (say) BT-70 airframe.

Big spin-fin rocket!

ghrocketman
02-26-2019, 02:46 PM
Weighing balsa with a digital scale to sort out decent pieces at a hobby shop is NOT an activity I would participate in. It should already be sorted and labeled like it was back in the 70's and 80's.
I would just order what I want from Sig if I was so inclined to need something specific like light/contest 1/4" Balsa.
My intent was to convey it's no longer easy to find decent light balsa of 1/4" thickness at an average hobby shop now.

Ez2cDave
02-26-2019, 06:28 PM
Okay I will do something radical and post an on-topic response.

The Apocalypse is nigh . . . LOL !

Dave F.

Ez2cDave
02-26-2019, 06:34 PM
Weighing balsa with a digital scale to sort out decent pieces at a hobby shop is NOT an activity I would participate in. It should already be sorted and labeled like it was back in the 70's and 80's.


There is no guarantee that it wasn't mixed-up by previous customers . . . Back in the day ( early-mid 1970's ), I used a small, handheld "postal scale".

https://i.pinimg.com/originals/e1/1c/8c/e11c8cd3b8ab6e7126a228c37fdcde06.jpg