Schweizer 1-26E ~ 1/2.5-scale Kit by Peter Goldsmith (Build thread by JimD)

[gunny11]

Good morning Tom, I new you would chime in. Lol. The 2 screws just hold the unit in the glider so it doesn't work it's way out from consecutive landings. I see something that maybe other people can't see or picture in their mind. When I first got the unit from Erich I just stuck it in the notched out keel (no bolts) of the 1/3 scale 2-33 and hooked up a rope to it and yanked on it just to play with it and it didn't even try to depart the keel.
will have to do a demo video.

[Swiss1]

I agree Gunny, the load is pulling forward, not down! I may use this idea on the new Musger!

[JimD]

Okay, I thought about it all night and I am going to redo the tow release mounting. I have an idea that does not involve water jet cutting metal or any other exotic parts, and is simple to make with what is available in the kit...

...stay tuned!

[Swiss1]

Make what Gunny suggested out of scrap ply!

[ErichS]

I like Gunny's idea for the tow release unit. Most of the force will be in the lateral direction not the vertical so the two screws will be just fine.

[Swiss1]

I agree Erich!

[Tom]

I like Gunny's idea for the tow release unit. Most of the force will be in the lateral direction not the vertical so the two screws will be just fine.

Hahahahaha......I’ve seen your tow’s......and many others and quite often the sailplane gets in the “high” tow position which in fact does put a vertical load on the assembly.......you guys are way over thinking this.......a solution looking for a problem!

[ARUP]

Agreed. Just use a properly sized loop. If things get pear shaped and you can't release quick enough the loop should break.

[Tom]

Agreed. Just use a properly sized loop. If things get pear shaped and you can't release quick enough the loop should break.

And the “magic” word is “should”!

[ARUP]

Lol!!! Don't you just love how I word my posts? I should have been a politician! The other magic words are 'properly sized loop'! Hahahahaha. Are there any 'Rules of Thumb' regarding model weight vs 'weak link' loop strength?

[ErichS]

Did some redesigning of the Tow release install this evening. This is a very rough design. But gives you guys some of the ideas or concepts that Gunny and myself talked about today. This system uses square-nuts inserted into the 3 keel plates which will hold the .020 thick spring steel cover plate. This would allow for tow-release removal for service if needed.




Di

[Mosquito]

You could lock me in a dungeon with all the computers at my disposal and only let me out if I could add neat graphics like you did above, and I would be found by future explorers in the next century. Nicely displayed!

[JimD]

Since the plane is going to need weight in the nose anyway, a little extra structure is not going to hurt. Here is my solution for a removable option.

First, the release seems to have way too many through bolts so we took out six of them. Then we made a box that the release slides up into. It will be held in place by two vertical screws (one in front and one in back) that will thread up into a T-nut in a top plywood plate. basically, the release will be captured between a top and bottom plate that squeeze between the verticals of the keel.

Not finished making all of the parts yet, but this gives the idea.

[gunny11]

Right on Erich. There you go Jim.

[JimD]

Fabricated the top plate that will hold the T-nuts.



Release will be captured between top and bottom plates.



Needed to provide a lip around the bottom plate for the 1/8" thick balsa sheeting to attach to. It would be great if this bottom plate could be machined out of aluminum and have counter sunk 6-32 screw holes.



1/8' balsa sheeting will fill in level with the 1/8" thick bottom retainer plate. These plates squeeze the release between the side keel pieces...This will NOT pull out!!!!



Inside fuselage looking at top plate with T-nuts installed.

[JimD]

Just to be even more OCD about this, we put filler blocks into the top plate that further lock in the top of the aluminum mount.





Then the servo tray was installed and the T-nuts epoxied in place.



Okay, I think I am happy with the tow release now!

[Swiss1]

Jim would it be possible to countersink the bottom ply plate so you could install flat head screws! Would look a little cleaner.

[gunny11]

Awesome Jim! Hey Erich, check this out....
i feel that the bolted aluminum side plates are stronger....

[stevekremer]

Very Nice Jim. way to go.

Steve K

[JimD]

The Model Box 2.0 put a fresh batch of Ultracoat, two A7050 Thin-Wing Servos and Hangar 9 control horns on my doorstep this afternoon!

Thank you Professor Hartmann (aka Swiss1)

If you need any hobby items, give Jeremy a call at the Model Box...great place to do business. I visited the store in January 2017 and it is without doubt the most impressive Hobby Store that I have ever been in!!!!! Here is a picture from my visit, but the picture does not do justice to this fine establishment.

[Steve P]

That handsome young Aussie lad went flying today. Cold outside, I bet it left him happy and warm inside!

[JimD]

You beat me to it...



Note the new Spektrum iX12 transmitter that was used...



Peter says he did loops, rolls, stall turns, and a speed run/flutter test (to make sure it is Len grade)...very happy with results!!!
,

[ARUP]

Staged! I wanna see in-flight pics! Anybody can hire a bum off the street to act as a model to hold a sailplane! So until then... I'm a Doubting Thomas! lol

[Mosquito]

Doubting Michael "Y'all!"