HappyRCFlyer
Active member
I've opted to try out covering a piece of scrap hot wire cut EPS with tissue using watered down pva/titebond to test it's strength and weight penalty for going this route. The piece came out far stronger then I could have imagined and the weight penalty was only 2 grams on this particular example, well within the tolerances to justify using on all of my EPS based planes. I'm going to be testing this with de-papered foam board next. You just brush on the glue and lay down the tissue, smoothing out the wrinkles and let it dry. I did both sides at once, I would recomend doing just one side at a time since it was a bit much to handle at the same time. This eliminates the need to add solid spars out of balsa/ply/carbon fiber, etc.,
Second topic on this one. I found out my laser cutter can cut black foam board, it's just a low powered diod laser cutter which doesn't cut through white foam board but this new capacity means i'm able to start producing foam board based kits in addition to the balsa and eps ones I already produce. I'm starting with this one that goes back into being open source for the DIY crowd that I originally created in 2004 out of blue foam after testing it out in a smaller version via. electric free flight, the RC version was using old brushed and nimh gear and was underpowered so more of a foot note back in the day that later went on to my surprise with someone that copied it and converted to foam board, adding bl and lipo and it became a design with cult following. It was originally called the Flying Potato chip, named that by the admin in one of the minor forums and I shared it at Watt Flyer and RC Universe back then along with the Geo-Bat team, long story there, it was renamed Nutball by the guy that copied the design so it is what it is to this day called that.
Going back to the original specs from memory, the saucerspan was around 27 inches. I opted to scale it back to 24" so it could be done up on the main sections of the middle taking up most of the width of a sheet of foam board and wing/dihedral sections taking up another sheet, they will be tab and slot connected. Take note, the winglets/dihedral sections being scaled closer to the original increases the center/flat lifting area, why the remake in 2008 had them wrong, he was going by just a photo I shared on the forums I suppose or creative liberty, it is actually counter productive since it reduced the lift area and overly done up dihedral is bad in cross winds. The rudder was close to the original, i modeled mine after a cub back then, I may revise it a bit to stand out from the rest there.
The reason it was tail feather control originally, I didn't have the gear for elevon mixing and I was just learning to fly. I went on with different shapes on the saucers including more complex dihedral patterns and to include aileron/elevator control which is what I used to learn how to fly with aileron control, still that solid body disc no matter how one goes about it traps air underneath and it has to flow out, one side or the other, like trying to stay balanced on a log that's floating in the water. Cutting a hole in the middle alieviates this problem which was explored in the 30's, and then, re-defined by the Geo-Bat team, of which I've been given endorsement and authorization to reproduce the Geo-bats for production on the kit lines. If you opt to go with the center cut out, you can increase it's glide ratio significantly by adding a lift, cambered airfoil on the h-stab section, it then functions as a tandem wing at that stage, it also reduces the amount of ballast needed in the nose.
I'm showing it on the drawing board along side of the FT one which itself is just a copy of the copy done up in 2008 and reviewing all of the other ones, they all kept to that same format with little to no real deviation upon.
Second topic on this one. I found out my laser cutter can cut black foam board, it's just a low powered diod laser cutter which doesn't cut through white foam board but this new capacity means i'm able to start producing foam board based kits in addition to the balsa and eps ones I already produce. I'm starting with this one that goes back into being open source for the DIY crowd that I originally created in 2004 out of blue foam after testing it out in a smaller version via. electric free flight, the RC version was using old brushed and nimh gear and was underpowered so more of a foot note back in the day that later went on to my surprise with someone that copied it and converted to foam board, adding bl and lipo and it became a design with cult following. It was originally called the Flying Potato chip, named that by the admin in one of the minor forums and I shared it at Watt Flyer and RC Universe back then along with the Geo-Bat team, long story there, it was renamed Nutball by the guy that copied the design so it is what it is to this day called that.
Going back to the original specs from memory, the saucerspan was around 27 inches. I opted to scale it back to 24" so it could be done up on the main sections of the middle taking up most of the width of a sheet of foam board and wing/dihedral sections taking up another sheet, they will be tab and slot connected. Take note, the winglets/dihedral sections being scaled closer to the original increases the center/flat lifting area, why the remake in 2008 had them wrong, he was going by just a photo I shared on the forums I suppose or creative liberty, it is actually counter productive since it reduced the lift area and overly done up dihedral is bad in cross winds. The rudder was close to the original, i modeled mine after a cub back then, I may revise it a bit to stand out from the rest there.
The reason it was tail feather control originally, I didn't have the gear for elevon mixing and I was just learning to fly. I went on with different shapes on the saucers including more complex dihedral patterns and to include aileron/elevator control which is what I used to learn how to fly with aileron control, still that solid body disc no matter how one goes about it traps air underneath and it has to flow out, one side or the other, like trying to stay balanced on a log that's floating in the water. Cutting a hole in the middle alieviates this problem which was explored in the 30's, and then, re-defined by the Geo-Bat team, of which I've been given endorsement and authorization to reproduce the Geo-bats for production on the kit lines. If you opt to go with the center cut out, you can increase it's glide ratio significantly by adding a lift, cambered airfoil on the h-stab section, it then functions as a tandem wing at that stage, it also reduces the amount of ballast needed in the nose.
I'm showing it on the drawing board along side of the FT one which itself is just a copy of the copy done up in 2008 and reviewing all of the other ones, they all kept to that same format with little to no real deviation upon.
