# Recent content by ULF

1. ### CriCri Composite

Yes, pultruided Yes, industrial pultruded rods are a must for spar caps. https://shop1.r-g.de/en/art/710101RPSALE50 I thinkI´ll buy 4 of those, they are long enough, and have plenty of meat to sand of. John.
2. ### CriCri Composite

Hi Billski, Bob mentioned you are an engineer, and I wanted to ask for your opinion. On aircraft, it is not uncommon, to oversize parts sometimes, for practical use, groundhandling and so on. I did some preliminary calculation about the size of the upper carbon spar capstripe, for 9g. The...
3. ### CriCri Composite

haha, well once every 5 years, on a windy day, Ill probably survive without prtmanent damage! I always wondered what that smell is. Many thanks to the master!
4. ### CriCri Composite

Hi there, Short pieces of 2ft, or under give excellent results hotwired. Very accurate cuts. John
5. ### CriCri Composite

Hi Bob, Searching for carbon fibers I came across bidirectional non- crimp fabric https://shop1.r-g.de/en/art/192150127-EBA, with unidirectional layers +45°/-45, there I saw, some +45°/-45°, and others -45°/+45°. Ihave never used such bidirectional stuff, I used plain weave, cut 45°. Do you...
6. ### CriCri Composite

Well, honeycomb building tehcnique is far beyond my abilities .
7. ### CriCri Composite

As model plane builder, they use one ort to layers of cellulose filler and sand the balsa, to prevet it to get soaked with the heavier resin. i dont know if that is acceptable or real airplanes. I guess Ill stay with PVC.
8. ### CriCri Composite

Well the size, 2,2m, where do those numbers come from? And then I ask myself wher does the 80kg emty weight come from? Do the engines weight so much moore than mine? (both may be 13kg).
9. ### CriCri Composite

No question, it is absolutely optimized, aerodynamically! But +8, -6g? Besides I doubt that one would be able to pull that kind of lift off a 3m2 ( 33sq.ft) large wing, with an airspeed of 150mph. I mean its designed to beat a fighter jet. That makes 80Kg.
10. ### CriCri Composite

You are right, Im not aiming to save a few pounds, Im trying to not produce weak spots, and not to waist weight. Im asking here and there, and try to estimate strenght, before I start to laminate. Sofar I have a pretty clear picture of how to make the wing: As mould Ill use wire cut pu...

12. ### CriCri Composite

On the original cricri the Fuel is in the pilots crotch, between his knees. To the solid core methode: The Cricri wing has 22% thickness. And Im planning on building a sprar for the entire bending moments for ~ +8 -6g. The skin needs only be tough on the D-cell. The rest could litterally be...
13. ### CriCri Composite

The total chord of the wing is 2ft, (24") , that is pretty much on the limit. For a RC model I could change aerodynamics, but not on a cricri that i would plan to fly in with. I dont dare. You seem to be experienced in that composite technique, may I ask what you do? My thought is. Build a...
14. ### CriCri Composite

Hi Bob, the HTML is not my thing. Thanks for sharing your experience with me! You know, I`m a epoxy- model plane builder, lately I finished a ULF-1 glider, and the dimensions of the cricri are so tempting to me. I´d like to fly in it. Each wing is only 2m ( 80in)span, with the spar sitcking...
15. ### CriCri Composite

Thanks, greate info! John