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Indoor Free Flight Forum => Bostonian => Topic started by: SvenH. on Jan 05, 2026, 02:28 AM

Title: Beancraft Banana_an Experiment
Post by: SvenH. on Jan 05, 2026, 02:28 AM
As a Newbie in Free-Flight with some experience in model-building (RC-Planes, RC-Sailboats, etc.) I was lately looking for a FF-Plane-to-build, to gain some experience in setup and trimming FF-Planes, plus as a Plattform for experimenting (Props, Rubber-Setups, Wing-Profiles, Power-Units (Rubber, Electric), etc.). Richard Crossley, who btw has some credits in me starting FF-Modelling, recommended to me the Boston Beancraft Banana as an easy and quick to build, robust, stable flying model, he has build quite a while ago and flown for more than a decade.
So I decided to give it a try. The source Richard sent me, contains also, in addition to the classic hand drawn, a vector-based version of the drawing, which is much easier to work with - a picture of it below, let me double-check with George and Richard, if it is ok to post the link to the drawing here, if yes I will do so later.
Title: Re: Beancraft Banana_an Experiment
Post by: Spiros on Jan 05, 2026, 08:53 AM
I'm looking forward to this. When finished with the two major projects, I will also make one!

Please if possible, post pictures!
Title: Re: Beancraft Banana_an Experiment
Post by: g_kandylakis on Jan 05, 2026, 10:16 AM
Hi Sven,

Links are fine to post.
Title: Re: Beancraft Banana_an Experiment
Post by: SvenH. on Jan 05, 2026, 12:37 PM
Quote from: Spiros on Jan 05, 2026, 08:53 AMPlease if possible, post pictures!

Of course, Spiros, of course I will show pictures here, just had some difficulties on uploading them, but also with your personal help I tzhink I might overcome them now...
Title: Re: Beancraft Banana_an Experiment
Post by: SvenH. on Jan 05, 2026, 12:39 PM
So, here's a picture of the plan with metric dimensions annotated, please pardon my bad handwriting.
Title: Re: Beancraft Banana_an Experiment
Post by: SvenH. on Jan 05, 2026, 01:18 PM
So I quickly set up a build-board with according partial drawing. I prefer using a XPS-Foam as base, and a Parchment-Paper, which I grease with some Bees-Wax hand cream (homemade by my dear wife), as a topper. I use the greased Parchment-Paper when I need to have a drawing as aguide underneath rather than Backing-Sheets as those are not really transparent and brown in color here in Germany.
Title: Re: Beancraft Banana_an Experiment
Post by: SvenH. on Jan 05, 2026, 01:20 PM
Here's a picture of my setup already carrying the precut balsa-sticks for the right side of the fuselage.
Title: Re: Beancraft Banana_an Experiment
Post by: SvenH. on Jan 05, 2026, 02:10 PM
One additional aspect on this build is testing a new-to-me glue, recomended by Spiros. Some might know it by it's original name "Clou Spannlack", actually a stiffening varnish / dope, based on Nitrocellulose-Acetate, but according to the experience by Spiros, especially on last years IIFI (his BD4 hit the ceiling Beam twice, undamaged, and just kept flying Video (https://www.youtube.com/watch?v=JyQBxEdzC2w) ), definitely something to give a try due to its flexibility and as I learned its low specific weight (much less than CA).
Unfortunately, the original Clou stuff is out of production now, but I found a guenerica produced by a small modelling-company here in Germany, so I ordered a small Tin Can...
Title: Re: Beancraft Banana_an Experiment
Post by: SvenH. on Jan 05, 2026, 02:25 PM
But there's more new stuff to come on this build, more new aspects to me. Spiros recommended, not to use, as I planned a mirrored drawing and a whole set-up for the left fuselage side

but to glue the balsa-sticks directly onto the right side, to make sure both sides are as similar as possible...
Title: Re: Beancraft Banana_an Experiment
Post by: SvenH. on Jan 05, 2026, 02:27 PM
So I did also follow this advice...
Title: Re: Beancraft Banana_an Experiment
Post by: SvenH. on Jan 05, 2026, 02:29 PM
Quote from: SvenH. on Jan 05, 2026, 02:25 PMBut there's more new stuff to come on this build, more new aspects to me. Spiros recommended, not to use, as I planned a mirrored drawing and awhole set-up for the left fuselage side
 
signal-2026-01-03-162858.jpeg

but to glue the balsa-sticks directly onto the right side, to make sure both sides are as similar as possible...


I don't know what went wrong on this post, why the picture emerged two times, may you George can explain that to me in a PM...
Title: Re: Beancraft Banana_an Experiment
Post by: Spiros on Jan 05, 2026, 02:48 PM
Great job!

BTW obviously I'm not a pioneer on this method, as it was tought to me by George. And honestly, I'm really happy with the way it works.

Can't wait to try the new dope! It will be interesting!
Title: Re: Beancraft Banana_an Experiment
Post by: g_kandylakis on Jan 05, 2026, 03:14 PM
Hi Sven, looking good!

About the picture attachment, you also inserted in your text (when you add an attachment there is an arrow on the top right corner, for insertion in the text, where you might want it. But it also appears at the end of the message as an attachment.

I edited your message and the second image is gone.


Slight note, when you make frames and there are parts to be cut out later, like the longerons at the rear end, make them larger. You can cut/sand them later, no need to go very close to the cut in advance. To close means they might be too short. If larger by 4-5mm, a slght sanding will allow a flush line with the upright, a perfect result.

Also, I like to use 15-20mm thick balsa as a building base. A bit sturdier than foam but not so hard to push pins into.

And last, in order to prevent accidental glueing the parts to the plan, I use small pieces of Scotch tape for each glue joint. Transparent, fixed in place, easy and clean.

Just as suggestions...

George
Title: Re: Beancraft Banana_an Experiment
Post by: Pulserudder on Jan 08, 2026, 02:19 AM
Quote from: Spiros on Jan 05, 2026, 08:53 AMI'm looking forward to this. When finished with the two major projects, I will also make one!

Please if possible, post pictures!

I remember when this model came out, though I don't think I have the particular magazine any more. I always had in mind to build one too.

Plans and construction article are available on Outerzone. Would there be any interest in a cook-up/group build?
Title: Re: Beancraft Banana_an Experiment
Post by: Spiros on Jan 11, 2026, 01:29 PM
That would be awsome!!

Sven, John Kourbanis and myself are building Bostonians, I'm the last one to be honest.

We could do a e-contest somehow!! Why not?
Title: Re: Beancraft Banana_an Experiment
Post by: SvenH. on Jan 17, 2026, 03:44 PM
Sounds good, so the competition is on, but I would suggest, that we open up a new thread for this, as this is the build report about my Boston Beancraft Banana, and I would like to keep it like that.
Title: Re: Beancraft Banana_an Experiment
Post by: SvenH. on Jan 17, 2026, 04:00 PM
After some absence here it is time to contiune the story of my Beancraft Banana. Work did of course continue and achieved some progress, so let's see...
Title: Re: Beancraft Banana_an Experiment
Post by: SvenH. on Jan 17, 2026, 04:05 PM
...where was I, ah yes, I glued the left side of the fuselage directly onto the right one. This worked quite well
Title: Re: Beancraft Banana_an Experiment
Post by: SvenH. on Jan 17, 2026, 04:09 PM
until I started to remove the double from the build-base after finished glue-up, but look yourself:
Title: Re: Beancraft Banana_an Experiment
Post by: SvenH. on Jan 17, 2026, 04:13 PM
Spiros commented this by "That's quite normal, no worries, you can gule them back on after you separated them from each other" (or something like that  ;)  ), which kept my spirit up high, plus reminded me on the fact, that there was another scary task to come...the split...oh oh...
Title: Re: Beancraft Banana_an Experiment
Post by: SvenH. on Jan 17, 2026, 04:20 PM
So I took the thinnest blade in my collection of Scalpels, I did not have any rasor-blade at hand even though Spiros insisted on me using that instead of a "thick" Scalpel. Maybe he was right, maybe it was my bad and too less use of glue, but the separation did not go that well, see below (upper Picture shows the right Fuselage after separation, the lower one left)
Title: Re: Beancraft Banana_an Experiment
Post by: SvenH. on Jan 17, 2026, 04:26 PM
But with some extra glue and some extra time spent on the fuselage parts finally both halfes were finished
Title: Re: Beancraft Banana_an Experiment
Post by: SvenH. on Jan 17, 2026, 04:37 PM
For the assemly-process of the two halfes and so creating a 3D-Structure, I decided to do each area, each tross if necessary, separately, though setting up the pieces on the base due to the drawing beneath and then gluing in the tross
Title: Re: Beancraft Banana_an Experiment
Post by: SvenH. on Jan 17, 2026, 04:42 PM
See below the 2nd set-up, the first of the bottom trosses
Title: Re: Beancraft Banana_an Experiment
Post by: SvenH. on Jan 17, 2026, 04:49 PM
This way I went all around, kind of at least, until I reached the inevitable more complex nose area, where the sides have to be bent to meet in the midle. Following my chosen method, I set up the fuselage once again, this time horizontically level (can bee seen in one of the previous pictures), so that I could use my 1-2-3 Blocks to push in the sides to their dedicated position, and keeping the sides square.
Title: Re: Beancraft Banana_an Experiment
Post by: Spiros on Jan 17, 2026, 05:11 PM
Beautiful construction!
Title: Re: Beancraft Banana_an Experiment
Post by: SvenH. on Jan 18, 2026, 02:42 PM
I decided to do the installation in the nose for the nose-block first (before finishing the glue-up at the rear). As mentioned before I use this build for testing several things I've seen at IIFI and/or YouTube that I find reasonable to have on a plane.
COncerning the nose I will follow the concept presented here (https://www.youtube.com/watch?v=sJkmyBo9zrg&list=PLP6c2w2UvGmeX5W-FBP4SbPbPydcHUBzG&index=4) by Tom Hallman, so I cut some thicker pieces of Balsa so that they work as connectors/brackets for the vertical walls that will guide the noseblock.
Title: Re: Beancraft Banana_an Experiment
Post by: SvenH. on Jan 18, 2026, 03:00 PM
But to be able to follow this plan, I have to do the first modification according to the original drawing. I have to install 2 new beams/sticks (see picture below) on the front-diagonal, in order to give the upper brackets a 2nd place to be glued on, otherwise they would be glued on one spot only, which would be very weak.