I bought two 1/8 NPT brass barbed nipples, and cut a few of the barbs off to shorten them, drilled a 3/8" hole in the top and bottom of the tank, and used permatex fuel tank epoxy to butter the threads and then screwed the nipples in. When set, I added the 1/4" tubing and some clamps, and had a nice gas gauge. And yes, I chewed through the fabric with my teeth, or at least it looks that way! I also show Bear Perkins kit that does the trick, too.
I ran all these numbers when I analyzed the Highwing LLC gear (made by Lowell Fitt for me in December) that I installed. The yellow spring that he provided me is a Danly IEM yellow spring that has 1450 Lb per inch, and compresses fully at 1.78" or 2600 lbs of force. (http://www.danly.com/cgi-bin/itemdisp.pl?item=18528). I don't know what the original red spring shown in the pics is, but the color says it is softer than the yellow, if it is a Danly. Assuming the two gear (Airdale and Highwing LLC) have the same general geometry, the big black spring that Fly-n-Low is using appears to have about 6" of working length till it compresses fully, and if the spring rate is 325 Lb per inch, it will flatten at 1950 lbs. That spring is weaker than the flat yellow one, and will flatten sooner and turn into a hard bar sooner. The original yellow spring flattens at 2600 lbs which equates to a 4 g landing, the black spring (if it is 325 lb/inch) will flatten at less than 3 g's . FYI, a 3 g landing is 8 ft/sec drop, a 4G landing is about 12 ft/sec. If the black spring is 375 lb/in, then it flattens at 2250 lbs, which is 3.5 g, still weaker than the yellow spring Highwing gave me.
At the Top, Mark. Here is a quick drawing, I'll get some photos later. My plane is an Avid, MKIV, so the original pedals are by design low mechanical advantage. Your Kitfox is already sweet in that department, from your photos. Note in the photo of my "new" brakes how much closer the pivot point has moved to the pedal, I have about 2.5 times more leverage and therefore more braking power for the same press of my toe brakes.
I finally gave up on my old Matco fat brake cylinders, and rebuilt my system. I installed the newer, slimmer Matco MC-4 cylinders with an external reservoir, and drilled the brake bellcrank on the pedals much closer to the pedal with a second 3/16" hole about 1" from the brake pedal hinge. as opposed to over 2" in the original config. This now gives me about 2 to 2.5 times the previous mechanical advantage. It took a while to bleed the brakes, I finally used the classic method with clear tube into a bottle and pressing the pedals hard. Now the brakes are excellent, I can hold the aircraft from rolling at 5800 rpm with a 670 engine! To clarify - the old cylinders are too fat to fit closer to the pedal, so the best mechanical advantage is only about 1:1, thus the pressure your feet build is limited. The new slim reservoir cylinder easily sits 1" closer, so with only one hole drilled, I doubled the brake power. I used the Matco reservoir kit, it had all the parts and the compression fittings were easy. The whole refit cost me $270 and 2 hours and now I have excellent brakes.
I just upgraded to Rotax 670 and added a belly radiator. I used an older kitfox one that Edmo sent me, they also sell them on ebay. I ran two U-bolts thru the floor that circled the two diagonal steel members that go from the center of the pedal area out and back to the outer frame. You can see one of them peeking out in the photo. I used a 1.5" x 3" aluminum box, as a mount, cut away to lighten it but also to get access to the bolts. The hose is 1' ID high temp silicone form Amazon, really flexible. It needs to be 2" lower, doing that this week.
Hey, I wasn't being critical, sorry if it came off that way. The MK IV Build manual is posted here http://www.avidfoxflyers.com/index.php?/topic/4220-avid-mk-iv-build-manual/ and if you download Section III, then look in section iii for Chapter 9, the flaperon build is described. But finding stuff in the build manual is a real pain, it took me a while to find it, and that is my manual posted there!
Cjflyer, I installed my pumps exactly that way, using a Facet 4 psi pump, and it all works perfectly. It is a requirement for the 670 which needs the extra fuel flow that the Facet is capable of. BTW, I one time bought a $10 ebay chinese knockoff pump that looks just like the Facett, and has the same markings. It lasted about 30 hours and died.
Did they use a foam core for the flaperons? I suppose I can de-construct the current ones and find out how they were built. Thanks. The build manual says the flaperons are entirely foam filled, except where the hinges are installed. The build manual section III chapter 9 is pretty clear on this.
Yes, if the bank is fully trimmed with back stick so it develops the load factor. And no if you do not trim into a zero altitude loss turn. The better way to say it is that at 2 G's the stall speed increases by 40%. 1.4 x 1.4 = 1.96, so that the V squared portion of the lift equation is satisfied - same wing, twice the lift needs 1.4 times the airspeed. But if you just bank, and allow altitude loss, no problem and no stall speed increase.