Kitfox Aircraft Stick and Rudder Stein Air Grove Aircraft TCW Technologies Dynon Avionics AeroLED MGL Avionics Leading Edge Airfoils Desser CPS Parts EarthX Batteries
Page 10 of 11 FirstFirst ... 67891011 LastLast
Results 91 to 100 of 102

Thread: Geek's STi Build

  1. #91
    Senior Member jiott's Avatar
    Join Date
    Jun 2010
    Location
    Portland, OR
    Posts
    2,682

    Default Re: Geek's STi Build

    Its not real clear in the manual, but if you look closely at the rib installation drawing it shows the stiffeners going the full length of the rib, so they actually butt up to the steel tubing on each end. I believe that is why the instructions say to put the stiffeners in AFTER gluing the ribs in place. Whether this is really necessary or not is probably open to opinion; however, my experience leads me to believe its a good idea. I did it on the horizontal stab but neglected to do this on the elevator. When heat shrinking the fabric (Polyfiber) to the final 350 degrees on the horizontal I had no problems, but when shrinking the elevator all the ribs that were not fully stiffened ended up "S" curved from the strong pull of the fabric. It was not too bad, but the small steel tubing in the rear was not real straight. Those 1/8" thick ribs have very little compressive strength anywhere they are not stiffened. Other results and opinions may vary.
    Jim Ott
    Portland, OR
    Kitfox SS7 flying
    Rotax 912ULS

  2. #92

    Join Date
    Nov 2019
    Location
    Leavenworth WA
    Posts
    135

    Default Re: Geek's STi Build

    Thanks Jim. Good input and obviously something I didn't consider. I'll have to do some looking into that and possibly others will chime in on what they did along with similar experiences.

    Appreciate the info.

    G
    Gary (Geek) Phenning
    Leavenworth (Not the Prison), WA
    Kitfox STi in Building Stage

  3. #93
    Senior Member
    Join Date
    Feb 2020
    Location
    Tacoma, WA
    Posts
    409

    Default Re: Geek's STi Build

    I was going to comment but decided to wait since my stab/elevator ribs were glued in when I got my project.

    For the horizontal, I looked at your pictures and decided you might get lucky.

    I can tell you to not try this with the vertical stab. Those ribs need to be flexed into place.
    Kitfox 5 (under construction)
    Citabria (sold)
    Commercial SE/ME, CFII

  4. #94
    Benbell4140's Avatar
    Join Date
    Jun 2010
    Location
    Broussard LA
    Posts
    109

    Default Re: Geek's STi Build

    I found it easy to “tack” the ribs and the stiffeners in place on the structure with a dab of CA glue that uses the spray accelerator. I just tacked them all in place and then came back with the hysol.


    Sent from my iPhone using Tapatalk
    Ben Bell
    Building 7 super sport
    O200 powered

  5. #95

    Join Date
    Nov 2019
    Location
    Leavenworth WA
    Posts
    135

    Default Re: Geek's STi Build

    Have been working on the horizontal stab and elevator end caps and the bearings. End caps are coming along getting Hysol'd on and now the shaping process begins. Also started working the bearings for the elevator on the stab. Kind of the standard pics of the bearing being worked while chucked up into a drill press. Had them set up so that they were oversized to press in after being in the freezer overnight. I used the Loctite 680 bearing retention fluid as called out in the instructions. (If you haven't done this step yet - be ready - that stuff sets up really fast and is really strong. If you think you have alot of time think again.) After learning on the first one, I pressed the rest of the bearings halfway in, then added the Loctite and finished the press. That bearing will never spin with that Loctite in there.

    G



    End Cap 1.jpgEnd Cap 3.jpgEnd Cap 4.jpgEnd Cap 5.jpgEnd Cap 6.jpgEnd Cap 9.jpgEnd Cap 8.jpgBearings 2.jpgBearings 3.jpgBearings 1.jpg
    Gary (Geek) Phenning
    Leavenworth (Not the Prison), WA
    Kitfox STi in Building Stage

  6. #96

    Join Date
    Nov 2019
    Location
    Leavenworth WA
    Posts
    135

    Default Re: Geek's STi Build

    Busy week between getting the house ready for Winter and working on the plane. I got the bushings for the elevator all fitted into the bearings on the horizontal stab. I used an older file (read not real aggressive in removing metal) and took the bushings down to a diameter of 0.312. Then used the suggested sand paper method to fine fit them. This took almost a day to complete. Started on coating the end caps with Hysol and giving them the final shape. My elevator was actually about 1/8 inch wider than the stab on one end so I made that end cap just a bit thicker to make them both the same width. If you measure the progress on the plane by how much Hysol you use - I finished my first cans!! While I was working the end caps I also varnished the ribs except for the ends where I would be applying the Hysol to glue them in. Hysol and varnish I understand don't make the best bond. Transferred the rib placement dimensions from the instructions to the assembly and then adjusted the ribs a bit to take advantage of the metal structure where it was available. I made sure the ribs were fitted perpendicular to the tubes with the hinges. Once I had them all dry fit I used my trusty aluminum angle pieces and CA glue to insure that the ribs were lined up on the stab and elevator and holding them in position to get the Hysol. Also by checking the distance between the two aluminum angles, I was able to be sure that the ribs were parallel with each other (checked my dry fitting job). Finally got the ribs Hysol'd on the upper side of the assembly. Will do the bottom side tomorrow.
    Attached Images Attached Images
    Gary (Geek) Phenning
    Leavenworth (Not the Prison), WA
    Kitfox STi in Building Stage

  7. #97

    Join Date
    Nov 2019
    Location
    Leavenworth WA
    Posts
    135

    Default Re: Geek's STi Build

    Worked on mounting the horizontal stab and the rudder today. Got the stab on the fuselage, attached the supports but haven't done the adjusting to verify the horizontal is perpendicular to the vertical stab. Fitted and drilled the front slide blocks. Attached the rudder and adjusted the attachment points so that the proper gap clearances of 1 1/2 inches on the top and 2 5/16 inches at the bottom between the rudder and the vertical stab. Most definitely had to run a tap through the threaded attachment points on the vertical stab to get the bearings to thread in far enough to set the proper gap.
    Attached Images Attached Images
    Gary (Geek) Phenning
    Leavenworth (Not the Prison), WA
    Kitfox STi in Building Stage

  8. #98

    Join Date
    Nov 2019
    Location
    Leavenworth WA
    Posts
    135

    Default Re: Geek's STi Build

    Did all the adjustments on the left and right horiz stab braces to place the stab perpendicular to the vertical stab. Had to be one of the easiest things I have done on the build. Measured from the top of the vertical to both tips of the stab as well as to where the brace mount was located on the stab. All the measurements were right on. Proceeded to mount the trim motor and ran into a bit of a wicket with the lower mount. The instructions call for the bolt to go through the mount, then a AN960-10 washer (going to call it a -10 washer from now on), a nylon washer, through the trim motor mount, a nylon washer, a -10 washer, through the other side of the mount, a -10 washer and the self locking nut (nothing called out between the collar and the mount). There was no way in God's green earth that was going to work and even look right. I even bent the mounts out a bit and those washers between the mount and the motor would not fit (and besides bending the mount just looked wrong!!). After playing with that for over an hour, I substituted the -10 washers for the thin version of the same washer (an AN960-10L that I will call -10L). So in the picture you can see that the mounts are not bent, the bolt goes through the mount, a -10L washer, a nylon washer, through the trim motor mount, a nylon washer, a -10L washer, through the other side of the mount, a -10 washer between the mount and the collar, through the collar, a -10L washer and the self locking nut. I torqued the nut to the 15 in/lb requirement and just have two thread showing through the top of the nut. Hence the -10L washer between the nut and collar. If anyone reading this sees something wrong with what I did, PLEASE let me know and provide me an option other than bending the mounts.

    So now that the trim motor is installed, I removed the horiz stab and am looks like the next item on the fun list are the ribs for the rudder.

    Trim Motor Mount.jpgHoriz Stab Brace.jpgHoriz Stab 6.jpgTrim Motor.jpg
    Gary (Geek) Phenning
    Leavenworth (Not the Prison), WA
    Kitfox STi in Building Stage

  9. #99
    Senior Member jrevens's Avatar
    Join Date
    Aug 2009
    Location
    Arvada, CO
    Posts
    1,956

    Default Re: Geek's STi Build

    You did well. In this kind of situation you use thin or thick washers, as necessary.
    John Evens
    Arvada, CO
    Kitfox SS7 N27JE

  10. #100
    Senior Member
    Join Date
    Feb 2020
    Location
    Tacoma, WA
    Posts
    409

    Default Re: Geek's STi Build

    As John said, you'll find many places on this build where you use a combination of -10 and -10L washers to make things fit just right.
    Kitfox 5 (under construction)
    Citabria (sold)
    Commercial SE/ME, CFII

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •