Activity Stream

Activity Stream

  1. dholly added a post in a topic How to tell if it's a MKIV   

    I notice on your Avid+ that the position of the pin bushings in the carry through tubes is different than mine. Hardly any of the bushing on mine is above the carry through tube. Very different. The bushings on my Mk-IV looked the same as my Avid+. I wonder why yours are different regarding bushing height? Now I'm curious what your Mk-IV looks like? Or Jack's C model?

    • 0
  2. racegunz added a post in a topic How to tell if it's a MKIV   

    thanks guys, lots to consider, the kit ofx kit is looking like the better deal right now, but i haven;t "seen" either one of them.
    • 0
  3. dholly added a post in a topic Avid Wingtip Kit   

    Randy ------------> go HERE
    • 0
  4. dholly added a topic in Fat Avids, Avid Plus and Airdale   

    Wing tips
    Randy -

    As you know, the wing tips supplied with the Avid+ kit are attached to a spar extension and, therefore, permanently fixed. I prefer removable tips for inspection and quick repair if necessary so I took a look around to see what might work. At the moment, I'm leaning towards a set of Hoerner-style 'Speedster' tips sourced from You can see from the following pics, the Kitfox 4-7 'laminar flow' rib profile designed by Harry Riblett is very close to Avid's flat-bottom 'speed wing' rib profile. Using the tips full width will only give me another couple/few inches per wing but I'm hoping the Hoerner style and shape will provide a bit more lift and speed than the oem Avid tips. Who knows, the big thing is removability and I prefer the looks over the Avid tips.

    Here is one of my Avid speed ribs next to the Hoerner style tip supplied with a friend's Kitfox 4-1200 kit.

    Top curve looks good.

    Bottom looks good too.

    Leading edge cuff is easily integrated.

    Only issue we found was length, but the good news is that Kitfox tips are supplied over-size and open at the trailing edge to allow custom fit by each builder.

    These tips were trimmed approx. 3" in length and 2" in width (to fit in his barn with wings folded), then trailing edge sealed.

    I think the extra trailing edge material will allow the KF tips to be fitted to the longer Avid speed ribs with very little modification.

    Now the issue becomes how to attach the tips. I have seen the tips attached directly to either the inboard or outboard cap strip of the tip rib with self-tapping screws. This typically requires the addition of an epoxy bead buildup along the cap strip/rib web junction to give additional material for the screws to grip into. I have eliminated this for aesthetic reasons, I simply think the tip sitting on top of and higher than the fabric as opposed to flush with the top wing surface looks like ass, especially if it's wavy. Some folks even put nutplates in the capstrip and it still looks like ass, IMHO. Not to mention a lot of work but to each his own I guess.

    Couple of comments on the KF list about attaching with invisible piano hinge. Yeah, it looks great but since I'm not looking for a Grand Champion trophy here the extra trouble to cover a bazillion rivets isn't worth it to me. Right now I'm thinking I'll probably just glue and rivet a strip of aluminum to the underside of the outboard tip rib cap strip to receive either self-tapping screws or floating nutplates like this.

    I would add a stiffener strip along the inside of the wing tip edge to strengthen and help make sure it lays tight along the edge rather than waving or oil canning. Maybe even glass in a couple foam ribs in the tip. Hopefully that will help minimize a couple of what sound like common problems when using screw heads directly on the f/g, ie. vibration causing paint chipping, hole elongation, etc. I was going to continue the fabric and tape past the rib and over the strip riveted to the rib, being careful to get a nice sharp edge at the 'step' between cap strip and backer strip. To keep it all flush, I just need to figure the correct thickness of the aluminum strip in the tip and install it after covering the wing because the thickness of the tip strip and the tip material must be equal to the cap strip thickness less whatever thickness the fabric + reinforcing tape + paint layer ends up being.

    Open to any alternatives, trying to K.I.S.S. to keep things moving.
    • 12 replies
  5. Av8r3400 added a post in a topic How to tell if it's a MKIV   

    Just for clarity, are you talking about the rotational orientation of the carry-through tube or bending the tube to make it "V" or "U" (exaggerated) shaped?
    • 0
  6. SuberAvid added a post in a topic How to tell if it's a MKIV   

    Good discussion. I don't know what to say about the ability to exchange wings from different Avids but I know that the amount that Jack and I had to bend our forward carry through tube was very close to the same, which made us think our Avid wings are very similar. There are going to be slight differences in the wing build and drilling for the pins so I am sure it would be difficult to switch them and get the pins and bolts in but they are very close, and our Avid+ fuselages were very close to the same dimensions but did not fit the wings.

    When I talked to Steve Windner about how to fix it he said to bend the front carry through tube, just be sure not to use too much heat; just cherry red. I built a jig off of my Avid fuselage by dropping long bolts through the pin tubes and welded the heads to a peice of square steel tube. I built a bending fork from pipe that fit over the carry through tube of the Avid+ and notched it to fit around the pin tubes. This gave me the leverage to bend the carry through tube ends and align the pin tubes until the jigs dropped in place. The final test was mounting the wings.

    Steve said that they would be fine left like that but if I was worried about it, to weld tabs between the pin tube and frame. I did that for my own peace of mind. I attached pictures of the tube ends after they were done.

    As far as Avids with the Sube engine, one of the guys up here has one, a MkIV on floats. I have never flown it but hope to get a chance to this summer. It does have quite a bit of lead in the back of the floats and on the tail spring. It was one of the main reasons for me to build the Avid+, since I wanted to use the Sube and was going to have my Avid streched until Steve talked me into the Avid+ fusalage.

    Back on track; if the work on the Avid you are looking at looks like it was well done, I obviously would not consider it a problem.


    • 0
  7. SuberAvid added a post in a topic Avid Wingtip Kit   


    Describe the removable wing tips you are going to use: What lengths does that give you? GW with and w/o tips? How are they taken on and off? Are these offered by Airdale?


    • 0
  8. dholly added a post in a topic How to tell if it's a MKIV   

  9. akflyer added a post in a topic How to tell if it's a MKIV   

    Dont know what to tell you on that one.. I can tell you for certain that the two guys up here that got the fat avid fuses had to bend the front carry through to make the existing wings from a MK IV and a C HH fit the fuse. Both are well documented and there was a line of communication with Avid/Airdale discussing the issue. I am sure that it has now been corrected. There were quite a few issues with the buy this fuse and just transfer all your stuff over from your existing plane. Control columns needed to be extended, wings did not line up etc. These issues are shown on this forum under the fat avid threads.

    • 0
  10. dholly added a post in a topic How to tell if it's a MKIV   

    No jig change. It's the same 27-1/2" (IIRC) front to rear bushing, center to center. I measured both my Mk-IV and Fat Avid and they were exactly the same within a knat's hair. Also, I had -zero- trouble mounting wings to my Fat Avid. The only difference between my and Jack and Randy's Fat Avid experience is that I built new wings. IMHO, the 'issues' both Jack and Randy faced were primarily related to fitting their existing wings to the Fat Avid fuse. Their wings were already built, doublers installed, pin holes drilled and fitted to their old plane's personal head rack carry through tube and bushing angle characteristics. Even if each Avid and Fat Avid frame was built on a jig, I think there is still a high probability weld creep etc. makes each one slightly different. And it certainly doesn't take much off to be a complete show stopper when it comes to pinning spars with no slop allowed. In any event, I doubt any two planes would be EXACTLY alike, so I suspect trying to fit wings from one Avid to another will likely never be a perfect plug and play. Some adjustment will be necessary and if you don't want to install new doublers and drill more holes in your spar, I guess the alternative is to get out a torch and persuade the carry through tube and bushing to meet up with your existing spar holes. Just glad I didn't have to deal with that.

    Based on the seller comment, not sure if this plane you're looking at is a partially finished rebuild project or an uncompleted new build? If a rebuild project, I would bet a pile of doughnuts the wings on it are not original. Which leads me to wonder why were the originals replaced... bent in an accident or ground loop?? Or if this is a brand new build, seems like the wings were not built to the instructions in the manual. Perhaps the wings were not attached before the wing tanks were 'glassed in' and the spars ended up more than the correct f/r width. That leads to deeper questions regarding builder competency and puts more than wings into question. I would look the wings over thoroughly and put a tape on all critical measures including wing twist and flapperon tail hinges etc. I would also ask some hard questions why it was necessary and check that carry through tube modification very carefully.

    I found the Sube mount comment interesting. The only thing I can come up with is that the vertical firewall height of the A-C models vs. the Mk-IV and Fat Avid were different. I don't know that to be the case but, assuming that's correct, if the engine mount was originally used on a Mk-IV and held up to an earlier model (which is it you are looking at?), it makes sense the lower legs would be too long. I've attached a pic from the 'old' Airdale that shows the firewall attach stations for a Sube engine mount on, I believe, a Mk-IV. Maybe that helps some. Everything I hear and read suggests the Sube is a heavy engine for a Mk-IV, and too much in the earlier Avids for safe CG without adding a lot of tail weight. Of course, in the experimental world there are several flying and almost anything goes, but you might be wise to reflect on both Jack and Randy's personal experience as Avid owners and ultimate decision to upgrade to a Fat Avid fuse when choosing to fly Sube.

    • 0
  11. Av8r3400 added a post in a topic How to tell if it's a MKIV   

    Steve Winder is gone. Talk to Brett at Airdale with questions. Get some photos and share them with Brett with your questions.

    I would be conserned with "Bending" the carry through tubes to make the wings fit. This fuselage was built and welded in a jig. Unless something else is bent or ??, it should go together without need of bending or more welding. Get some photos of this and share that with Brett for his opinion before you make a decision...

    IMO - He's right. The Subaru engine is too heavy for a good performing Avid.

    (Leni - I've worked with the welding jig for the Avid/Fat Avid Fuselage at Airdale. I don't follow why that tube would need to be "Bent" other than something else is out of position.)
    • 0
  12. akflyer added a post in a topic How to tell if it's a MKIV   

    well I would say that someplace along the line, the jig for the avid fuse was changed as the guys building the fat avids that were going to use their existing wings had to bend the tubes on the fuse to make them fit the wings also. I know that Jack and Randy both had to "modify" the wing attach points on their planes to make the wings fit. I know they both talked to Steve Winder at length about it and that was the recommendation from the factory. I would not let it scare me away from the plane.

    have the guy take some pictures of it and post them up so we can see if this was the same issue that Randy and Jack had.

    • 0
  13. racegunz added a post in a topic How to tell if it's a MKIV   

    Ok here's the scoop from the guy with the Avid, why would he have to "bend" the cross over tubes? what do you guys think?

    (complete fuselage with landing gear mounted
    wings covered in ceconite thru nitrate (14' long)
    aluminum flaperons
    rudder, stabilizer, elevator covered with ceconite thru nitrate
    Subaru E-81 engine with belt reduction, alternator, and starter
    twin electronic ignitions
    3-bladed Warp drive prop
    radiator for engine
    fiberglass top and bottom cowling from other aircraft
    removable turtle deck made with composites
    fiberglass interior seat and cloth
    new fiberglass panel
    lexan material for windshield and side windows.
    airspeed, altimeter, oil pressure and temp, tachometer, hour meter
    fabric to complete fuselage.
    nitrate and butyrate coatings to finish project
    4 gallons of butyrate paint Daytona White
    AN hardware to finish project
    electric servo trim control which I purchased extra
    two complete instruction manuals with pictures
    builder's log

    To complete the plane, you will need to buy some finishing tapes, more paint, maybe a few nuts and bolts,

    here are some other details so there are no surprises
    1. I had to bend the front wing attach crossover tube slightly to get the wing bolts to fit. It was professionally reinforced (welded). It won't be visible on the completed airplane. I meant to take a picture of it but I forgot. I can still get one.
    2. The Subaru motor mount will have to be modified. It came from a later model which had a deeper fuselage. The bottom attach points on the motor mount will have to be raised to fit the airframe. You could talk to Steve Winder at Airdale Aircraft company for more information.

    I would recommend that you buy just the plane kit minus the engine. In my opinion, the engine is a bit heavy for the plane. The recommended engine originally was a Rotax 582. I will sell just the plane kit for $7,500. I have a total of about $13,000 invested so far plus hundreds of hours of labor. )
    • 0
  14. dholly added a topic in For Sale and wanted, you got it, I want it   

    Avid Wingtip Kit

    I am fitting removable tips and have no use for the originals. Thought I'd post in case anyone had an interest before I try to return for credit on other stuff I need to purchase.


    (1) W-35: right f/g wing tip
    (1) W-36: left f/g wing tip
    (2) W-22: 23" x 1" o.d. x .049" wall alum spar extension tubes
    (2) W-34: 18" x .75" o.d. x .035" wall alum wing tip extension tubes
    (2) W-23A: spar extension blocks

    Note: these spar extension tubes are pre-notched by Airdale... pretty slick

    (pics attached)

    • 2 replies
  15. Av8r3400 added a post in a topic 2 Stroke Oil   

    I went to a symposium at the EAA founder's wing this past weekend and LEAF (One of the three Rotax approved shops in the US) was presenting (among others). One of the topics Brian from LEAF spoke about was oils.

    They used to recommend the Pennsoil 2-stroke oil, but since that is no longer manufactured, they are now recommending Aeroshell Sport +2 oil for the 2-strokes.

    Just another option....


    • 0
  16. horsepower added a post in a topic 2 Stroke Oil   

    Thanks Leni,It is my understanding that Nissan oil and Yamalube are the same thing so I will give it a whirl.Randy
    • 0
  17. akflyer added a post in a topic 2 Stroke Oil   

    I have never run the nissan oil, but we run the Citgo Sea n Ski oil in our snowmachines and planes. It is Yamalube with a different wrapper on it. We have been running it for years and 100s of thousands of miles in various snow machines. Never has an oil related issue with any of the sleds or planes so far.

    • 0
  18. horsepower added a topic in Rotax and other engines   

    2 Stroke Oil
    Im not there yet but getting closer to mounting my 582 on the Skyraider.Was wondering what you guys run for oil, mine is oil injected if that makes a difference.I sell outboard motors and was wondering if you can run Nissan outboard oil.It is 50 percent mineral base and 50 percent synthetic made for direct fuel injection.I was told that you shouldnt run outboard oil but thought I would ask the hard core 2 strokers.Thanks Randy
    • 5 replies
  19. saskavid added a post in a topic Pic request   

    Regarding the matco link above, the most revealing yet sorta hidden,and not readily known thing I can show to yaall about pedal ratio appears in diagram 3, the illustration on the right side, there is some writing that says PERP DIST TO MC CENTERLINE. Which unabrevated reads perpindicular distance to master cylinder center line, basically means the shortest distance from the pivot point formed between the brake pedal and rudder pedal to a line running directly down the center of the brake ram.So with a mc-4 type brake ram bolted to the stock avid rudder bar attachment point, you can make that distance .5 of an inch.(the ram shaft is 3/8 dia and the rudder bar is 5/8 so half of each added together is 1/2 in)Divide that number into the pedal height of 2.65 and the resulting start pedal ratio is 5.3 to 1.With activation, the shorter the mc-4 ram you use the closer it stays to the pivot point, and the more leverage you maintain. The 6.5 inch length is the off the shelf optimum. 6.0 is possible but then the clevis hits the back of the rudder bar first and start leverage cuts back to 4.7 to 1, with activation ends up being a pedal ratio only .08 higher than the 6.5 delivers.(basically an undetectable ammount)

    • 0
  20. jackak added a post in a topic Need some verification   

    There should be a large area washer outboard of the three rod ends that are not inside a bracket. The two on the upper end of the flap links and the upper end of the one that attaches to the mixer and the aileron bellcrank. They're placed there to keep the rod end from coming off if the bearing fails. It's hard to see this in the construction manual, they all look like large area washers. Looking at that same manual it looks like there are several places on the mixer where self locking nuts are used, but I'd go for safety, not convienence. Another picky thing if I might, I'd bend the ends of the cotter keys tight against the nuts. I don't know how many times I cut myself when I didn't and went back in to work in an area with as many castillated nuts as the mixer has. Former engine and prop mech on C-123s, C-54s and T-29s.
    • 0
  21. racegunz added a post in a topic How to tell if it's a MKIV   

    Well I'm waiting for the man with the avid to send me some more pics to see if its worth the drive to go and see, also been looking at a kitfox 4 kit but he wants too much (in my humble opinion) if I decide on the kit fox I'll give you a shout. I don't know if it would work on the avid or not??
    • 0
  22. C5Engineer added a post in a topic Need some verification   

    My stick does move a little bit.. I was wondering what was causing that. What works to lube the flaperon hinges?
    • 0
  23. akflyer added a post in a topic Need some verification   

    have you disconnected the flaperons just inside the fuse at the top of the control rod and checked that each flaperon takes the same force to move up and down? if one is a little sticky, I can see it not moving as much as the other and giving you a bit of an asymetrical roll input when you pull the flaps on. Mine had a sticky flaperon and when I pulled the flaps on, the control stick would go full left if I was not hanging onto it. if this is playing into your rolling issues or not.

    • 0
  24. C5Engineer added a post in a topic Need some verification   

    Leni I have my flaperons set up so that mine flies hands off with the flaps full up and about 57-5800 rpm. I can only trim nose down. If I'm flying down low I pull on some flap to relieve the roll forces and just hold back pressure. The issue I'm having is when I pull on a couple of degrees I get a fairly strong rolling moment to the right and I can't figure out why. It also takes WAY more rudder to coordinate a turn to the right. It almost takes top pedal to keep the ball centered when I turn to the left. I knew it would be different but it seemed a little excessive to me.

    There's only two nylocks on the mixer box. The one where the flaperon linkage connects to the mixer box should be a castle not sure now I missed that. The one where the rod ends are I left a nylock because up until recently I was playing with my flaperon settings a lot and got tired of pulling a pin in and out. There's very little movement there unless your pulling flaps on and off all the time which I don't.

    The only reason I can see why I'm getting a roll is one flap is coming on more than the other. I need to get out my control surface throw and try different flap settings and see exactly what they are doing and why. Looking at the linkage everything appears to be working perfectly symmetrical.

    Jack can you circle on one of those pictures where I should have the big washers? I set it back up the exact way it was when I got the airplane but that does not mean it's right by any means. Also no I wasn't still working on it I took these pics right before I flew yesterday. I've put 48 hours on it like this but if it's wrong I'd like to fix it. The builders manual sucks for stuff like this and I'm still learning.
    • 0
  25. akflyer added a post in a topic How to tell if it's a MKIV   

    I dont think it would work for me. I am not sure if the firewall pattern is the same or not. I would probably be better off just starting from scratch as the new engine has exhaust and intake on the same side etc... But thanks for the offer!

    • 0