I did a 50% pre stretch (starting with 20 cm pulling it to 30 cm) before applying the wrapping and yes I did a double wrapping. I don't think it is needed to prevent slipping but if one wire breaks hopefully the other still holds.Have been using them for over 3 years and done some pretty bad landings without seeing any degradation in the wrappings or tendency to slippage.
This little tool makes it really easy to make the wrapping. I would say say the time to make it is almost gained back when making the second set.
A little neoprene glue add to the friction between the cords.
A simple cotton band glued with textile glue protects the wrappings. And a shrink rapping gives a nice final touch as well as protection.
...and I just made 5 new sets for Avid pilot friends here in France... I have also made a new set of "horisontal-between-the-landing-legs-bungees-to-replace-the-seat-struss-breaking-safety-wire" using the same wrapping method. I think wire wrapping is less agressive to the bungees than the metal clamps.
Brake fluid compatibility, the other way around problem... I have Matco brake calipers and brake cylinders set up for 5606 or DOT5 as recomended by Matco. In my specific setup (will tell you about it later) I have an additional master cylinder. I bought one specific 5606/Dot5 for experimental aircraft and it turned out to be a high priced piece of... It leaks, it doesn't work and isn't worth the plastic it is made of... But I happened to have a Chineese motorcyle break cylinder, brand new, never had a drop of oil in it. There is no indication on what brake fluid should be used but we can assume it is not military grade 5606. DOT 3/4 is more likey. We know (because we have been told so...) that DOT 3/4/5.1 will do massive harm to o-rings and other seals made for 5606, and we don't want to try... Here is my question: How will "DOT 3/4/5.1" o-rings and seals react on 5606? If they are expected to react, deteriorate and start to leak, after how long time? I filled up the master cylinder with red 5606 fluid, purged it, and applied pressure. Works great, but that was just a few days ago...
If user friendliness is a factor you can also take a look at Oratex. No solvants what so ever, no smells, no paint, no pain. It is so clean to work with you can do it in your living room.The end result will never be as perfect as "traditional just out of the paint box" but it looks very good and age very well. No paint that can crack or peel off. A great weight saver (saved somewhere between 5 a 7 kg on my Avid Flyer and had to reajust the CG...). As an example, including glue, covering both wings (left and right) is less than 3 kg of Oratex covering. It might appear expensive by the meter but as it is all inclusive the price comes out pretty much the same in the end as Stewart. Unless you have to pay someone to do the paint job for you... There are many posts on Oratex in the forum if you search for it and several of us have personal experiences to share. It is worth to take a look at.
Some ideas in regards to cargo bags... It is not that hard to do yourself, or ask whoever has the sewing machine to help you. I made a hanging bag behind the seats. It has 2 aluminum tube frames. The top frame can be separate in 2 "U" shapes so it can be easily removed when folding the wings.
The lower frame hold a stiff bottom plate.
The fabric is folded over the frame and attached with Velcro. The bag is then attached to the existing tubes with some tent clips I found on Amazon... https://www.amazon.fr/MagiDeal-10pcs-Crochet-Plastique-10mm-13mm/dp/B019C3WKHQ/ref=cm_wl_huc_item (the link is to the French Amazon as I, after just a short search, could not find them on .com) there are 2 size, one fit the smaller tubes and the other the bigger tubes...
The 'behind the head bag" clips to the tubes with the same kind of tent clips and can easily be detached and carried around as I made a handle on the rear side.
The leather details are just for fun and requires a rather solid sewing machine. I happen to have an old Singer with a hand crank, but without the leather trimmings the rest could be done on and machine. I started by doing a prop of paper and adhesive tape and then used the parts as a pattern.
Hej Anders! just out of curiosity, is there a stall speed limit for ultra lights in Sweden? Here in France, where I live and fly even if I Swedish, the Avid with speed wing cannot be registred as ultralight due to the higher stall speed. Othewise the idea of having both sets of wings is interesting and could save some time on longer flights. Vänlig hälsning, Fred(rik)
I was seriously considering a 670 but they are hard to find and spares are sparse... as you know, I got the Simonini Victor 2 92hp 2 stroke. Weight and size as 582. Light engines is the way to go for those planes - and no, I really don’t think 2 strokes are more prone to failures than complex 4 strokes.
Brooks, this is actually an interesting brake setup... do try a toe brake conversion but don't throw away this stuff... you might want to give it a second thought one day! Normally when braking your engine will be on idle so no throttle to manage and the throttle hand will be free for braking. I think you will find it easier to brake evenly with the two levers in one hand than with the feets that at the same time will control the rudder (or tail wheel depending on speed). And yes, the KitFox pedals are better than the original Avid pedals, actually any pedals are better...
"I think the extra shock provided by reaching the end of the slack in the safety cable buckles the seat truss." I can confirm this is true... Been there, done that (even documented in a film - "I had a dream"). If the safety cable is there to protect the prop, by breaking the seat struss instead, it is a bad calculation... particularly now when we have found the magic and inexpensive NR-props... I have removed the struss breaking safety cable and installed a 2 wrap horisontal rater stiff bungee between the legs:
It only comes into play at any greater deflection and hardly at all at normal landings. I have had at least one landing that could compare to when I (the safety cable) broke the seat struss and had no issues, no prop strike or other damage.