Wet Wing installation

PROSEAL

When it comes time to mix the proseal for the wet tanks, it is important that you follow the Proseal spec sheets for the mixing procedure. To do this you will need to have a gram scale for measuring. Please follow the spec sheets for proper mixing.

Sloshing compound can be used as a precaution against small leaks. We recommend PR-1005L (Mil Spec on Data Sheet) or equivalent. Again if you decide to use this, please follow the instruction with the sloshing compound.

. *Be sure to use Proseal where required to seal between all mating surfaces of ribs, spars, spar caps, etc. during final assembly of the fuel tank. More is better than not enough rather than have leaks later.*

  1. Remove the wing skins.
  2. Fit a fuel tank bulkhead (W-157) to each bay of each fuel tank. Note that the side flanges of the bulkheads are joggled to fit the stiffening swages in the wing ribs. The flanges of the bulkheads face forward into the tank. Wing Figure 72. Be sure that the bulkheads are properly seated in the ribs, i.e. the center of the bulkhead side flange must be lined up with the center of the rib swages. Wing Figure 75. Although reversing these would put the rivets outside the tank, this would leave an extra large gap at the top and/or bottom. It's important that the tops and bottoms of the bulkheads be even with the tops and bottoms of the ribs. (may require a spacer)

    3. Wing Figure 72 Wet wing over view

  3. Drill a 3/32" hole through the un-joggled end of the bulkhead upper flange as per Wing Figure 73

    4. Wing Figure 73 fuel bulkheads step 1

  4. Repeat for bottom flange.
  5. Mark a rivet pattern on the side flanges of two (W-157) bulkheads (as in Wing Figure 74) My spacing worked out to a hole every 1.75cm. (1.75,3.5,5.25,7,8.75,10.5,12.25,14,15.75 from the first hole. Drill the ten equally spaced 3/32" holes through the side flanges. Fit the bulkheads into the wing bays 1 and 3 ensuring that the side flanges are properly aligned on the rib swages, (as in Wing Figure 75).and held against the bottom skin then drill and cleco to the ribs.)

    6. Wing Figure 74 fuel bulkheads step 2

  6. Remove the bulkheads, mark a centre line on the remaining bulkhead, insert it into the centre bay 2 and use the just drilled holes in ribs 2 and 3 to line this up and drill.
  7. Bend the top flanges of all the bulkheads to match the camber of the top of the ribs as close as possible.
  8. Drill 1/2" flow holes in the middle baffle ribs as in figure 4. Drill the holes as close as possible to the bottom rear corner of the rib to ensure the maximum useable fuel. Wing Figure 75.

    9. Wing Figure 75 Fuel tank flow holes

  9. Install 2 baffle plates on each of the inside tank ribs, i.e. ribs 2 and 3. These can be made from .025" material (W-170). See Wing Figure 76. The baffle plates are attached to block a portion of the lightening holes on each rib. Make 2 for each wing starting with two pieces 3 ½ by 7 7/8 and two pieces 4 ½ by 7 ¼". Trim and bend as shown. These can be riveted in place now. Do not use chromate where they join.

    10. Wing Figure 76 Fuel tank baffle location

  10. With the ribs back in and the fuel tank bulkhead side flanges fitted, cleco the top tank skin onto the wing structure and rotate the wing onto it's back..
  11. Back drill through the bulkheads into the top tank skin to find the location holes. Cleco the bulkheads in place. Note: If a bulkhead has been located correctly on the swages, one of the existing holes in the main rib upper flanges should almost line-up with the center of the bulkhead (W-157) upper flange. These holes, (approximately 3) even if of minimal edge distance, may be used and drilled to #30. For existing rib holes that do not line-up with a bulkhead flange, (W-157) interpitch a new 3/32" hole in the rib flange row as required.
  12. Cleco the bottom tank skin on and flip the wing right side up. On the top tank skin mark a line between the location holes for each bulkhead. Drill 13 more evenly spaced holes between the two original holes for a total of 15 evenly spaced holes. (Spacing is approx. 3/4")
  13. Drill 3/32" holes between the existing holes on the solid ribs 1 and 4 and the main spar where the tank skin covers it. The leading edge skin should be on for this step.
  14. Drill a #40 hole in the top tank skin 1 7/8" from each edge in the corner shown in Wing Figure 77 this will be the centre of the fuel filler hole.

    15. Wing Figure 77 Fuel filler location

  15. Remove the top tank skin and repeat steps 184) to 186) for the bottom skin.
  16. Redrill the fuel tank bulkhead (W-157) side flanges to #30, remove bulkheads, deburr all #30 holes in bulkhead and ribs and recleco into wing.
  17. Install the top wing skin and tank skin. Mark a line 5/16" in from the outboard edge of the tank skin and another a further 3/8" in. (These lines will be between the tank skin edge and the #4 rib). Starting with the line closest to the rib and 2 cm in from the main spar rivet line mark and drill a 3/32" hole every 2 cm through the tank and wing skins. Avoid holes in the area of the stringers. Do the same for the outermost line starting 1cm from the main spar rivet line. These holes will be used to attach the main wing skin to the tank skin after the tank is prosealed and tested for leaks. Be sure to maintain the minimum edge distance of 5/16" for all rivets. On newer tank skins there may be enough metal to parallel these 2 rows but on older skins they will most likely need to be staggered. Wing Figure 78
  18. At the rear of the wet tank bulkheads mark a line parallel to the bulkhead rivet holes and 9/16" away on top of the wet tanks skin. Mark a second line 1" away. Drill 13 evenly spaced 3/32" holes on the line 1" out and 7 evenly spaced holes on the 1/2" line between each rib .Redrill all holes to #30. Wing Figure 78
  19. Flip the wing upside down and mark the outside edge of rib 4 and the backs of the bulkheads on the main wing skin (W-126)

    20. Wing Figure 78 Top skin tank cutout

  20. Remove the skins and where the 2 lines intersect drill a ¼" hole. Cut out the area of the wet tank along these lines. Be sure a minimum of ¼" edge distance is maintained from the hole centers of the 1/2" line to the cut edge. Deburr all holes and skin edges. Wing Figure 78
  21. Install the bottom wing skin and the bottom tanks skin. Repeat step 190) for the bottom skins.
  22. Put another line of holes parallel and equal to the stringer holes about ½ way between the bulkhead and stringer rows of rivets. Be sure to maintain the 5/16" edge distance and the minimum ½" rivet to rivet distance. Wing Figure 79.

    23. Wing Figure 79 Bottom skin tank cutout

  23. Repeat steps 193) and 193)for the bottom skins. See for a side view of the rivet rows at the rear of the tank.

    24. Wing Figure 80 Tank rear rivets side view

  24. Drill 12 evenly spaced holes through the Fuel filler flange (4808-5). Cut a 2 ¼" hole in the wet tank skin at the centre of the filler hole drilled in step 187 and Wing Figure 81

    25. Wing Figure 81 Fuel tank filler

  25. Remove the root rib #1. Trim a fuel tank outlet (W-49) to fit the upper front of the root rib Drill five #30 holes through the flange into the root rib. Note locate the fuel tank outlet as close as possible to the upper forward corner of the rib. It may be necessary to flatten with a hammer and dolly the stiffening swage of the rib in the immediate are of the fuel tank outlet. Wing Figure 82

    26. Wing Figure 82 Fuel outlets

  26. Trim a fuel tank outlet (W-160) to fit at the lower rear corner of the root rib just in front of the bulkhead flange. Drill 5 #30 holes to mount as in Wing Figure 82. Flatten stiffening swages if necessary. This outlet will be used for fuel flow. Install an additional outlet W-159 near the front as shown. This is for the fuel gauge. (SB 070395RB)

    27. Note: you may find it easier to make the following gussetts with the ribs out of the wings

  27. Make gussets from ST-40 to cover the stringer holes in the root rib #1. Install on the side of the flange and under it. Wing Figure 83

    28. Wing Figure 83 Fuel tank gussets 1

  28. For the cutaway on the rib at the main spar close the opening with corner bracket made from .032.. Wing Figure 84

    29. Wing Figure 84 Fuel tank gussets 2

  29. Where the outboard solid wing rib is cut away for the spar cap bend up a corner bracket as in Wing Figure 85

    30. Wing Figure 85 Fuel tank gussets 3

  30. Where the stringers pass through the ribs make up a shape to go around the stringer and close off most of the hole. Wing Figure 86

    31. Wing Figure 86 Fuel tank gussets 4

  31. Drill 5 evenly spaced holes in the tank drain outlet (W-159) and install it near the rear root corner of the bottom wet tank skin keeping it clear of any flanges. Attach on the outside as shown.Wing Figure 87

    32. Wing Figure 87 Fuel tank drain

  32. Trim the top and bottom tank skins as shown. Leave up to 3/8" when available. Wing Figure 88

    33. Wing Figure 88 Tank skin trimming

    Special Notes:

    ALWAYS WEAR RUBBER GLOVES!!

    Using a plastic bag and wooden stir sticks to spread the proseal out will make the job easier!!

    The shelf life of P/S 890 Class B is at least 9 months when stored at temperatures below 80 degrees F in the original, unopened containers. Slight changes in the application properties may occur during storage, but these changes should not affect the performance properties of the cured material. It is recommended that you store P/S 890 in the refrigerator to extend its shelf life until it is ready to be used.

  33. Deburr all holes and edges. Clean all parts with MEK in the area of the tank including all of the leading edge skin and mating surfaces. Scotch bright all mating surfaces and remove dust with a clean dry cloth. All parts in the leading edge area outside the tank should be chromated at this time.
  34. Follow the Proseal mixing instructions carefully and mix up enough proseal to do only what you can accomplish in the allotted time Proseal the tank ribs to the main spar and leading edge ribs using tanks (RR-6403) rivets after first coating the main rib to main spar mating surfaces.
  35. After chromating rivet the rear of ribs 1 to 4 to the rear spar.
  36. Coat the fuel tank bulkhead to rib contact surfaces with proseal and rivet with tank rivets. .
  37. Proseal and rivet the fuel tank outlets on the root rib W-49, W-159, and W-160 with fuel tank rivets.
  38. Proseal and rivet the water drain outlet W-159 to the bottom tank surface using tank rivets.
  39. Proseal and rivet the fuel filler 4808-5 to the top tank skin with tank rivets
  40. Proseal and rivet the various gussets on rib #1 and #4 top and bottom using tank rivets..
  41. Fill any remaining holes in ribs 1 and 4 with 3/16" avex rivets dipped in proseal and covered over on the inside of the tank and then proseal and rivet main and leading edge ribs 1 to 4 to the main spar using tank rivets. (coat inside surfaces with proseal and chromate the outer.).
  42. With the wing upside down and the top wing skin cleco'd in place, level the wing. Slide the stringers in and be sure the stringers are in the right place and orientation. Apply proseal to the main spar, ribs 1 and 4, along the tops of the bulkheads and the stringers in the tank area. Coat the corresponding surfaces of the bottom tank skin. Have several pieces of 1/8" welding rod available and place one in a hole near each corner of the tank plus one in each stringer in the first hole near the root rib.
  43. With someone giving you a hand place the bottom tank skin on these welding rods (make sure you have the rods in the correct matching holes in the skin) let the skin slide down onto the wet proseal.
  44. Cleco the tank skin in place and proceed to rivet using the tank rivets (RR-6403). Dipping each rivet in proseal will help prevent leaks and keeping a can of MEK available to throw used clecos in will help assure their future reuse. When riveting along the main spar be sure the leading edge skin to tank skin surfaces have a coating of chromate and is riveted at the same time, but only in the area of the tank.. Be prepared to clean your rivet gun several times during this process to keep it from getting gummed up with proseal.
  45. Flip the wing right side up and liberally coat the areas where the lower stringers enter the tank, around the various gussets and anyplace else where you think it might leak. Also seal the ends of all rivets in the tank at this time
  46. Ensure that all excess proseal is removed from the skin before it dries as it is very difficult to remove after the fact. Flip wing over and cleco bottom wing skin in place for rigidity. Flip back over and level.
  47. Chromate the skin doubler made in wing step 157) and rivet to the leading edge skin
  48. Chromate the mating surfaces of the strut attachments and doublers W-134, W-110, W-111, and bolt and torque them to the main spar.. All mating surfaces for the leading edge skin and leading edge ribs should also be chromated at this time.

    49. Wing Figure 89 Wing strut attachment

  49. After an adequate curing time (at least 24 hours) the top tank skin may be installed. (I recoated all seams and rivets with the brushable version of proseal at this time before putting the top tank skin on.) Double check for any pin holes or gaps etc. that may still exist from previous bead sealing. Slide the stringers into the correct positions. Apply a liberal amount of proseal to all mating surfaces of the bulkheads, ribs and spar etc. and be sure to dip all rivets before installation. Use the same procedure as for the bottom tank skin. Note: Ensure that the leading edge skin is over top of the tank skin and that their mating surfaces are chromated. Don't be stingy with the proseal at this point because once it's closed up it will be difficult to fix leaks..
  50. It's recommended that the proseal be allowed to set for 72 hours before pressure testing.
  51. Put a safe or rubber glove over the fuel tank filler, attach a bicycle pump or similar device to one of the fuel flanges, plug the others and apply enough pressure to just inflate the glove. Check for and repair any leaks found. Do not over pressurize.
  52. When the wing will hold pressure for several days the tank can be considered fuel tight. Be aware that temperature changes could affect the glove's inflation appearance.
  53. Slip the top wing under the tanks skins and leading edge skin and cleco in place and put the wing on its back..

    54. Wing Figure 90 Aileron position template

  54. Glue the template in Wing Figure 90 to a stiff piece of thin cardboard.
  55. Draw a line from the pivot position to the trailing edge on each end of the ailerons for the right wing. Wing Figure 91.

    56. Wing Figure 91 Aileron neutral position line

  56. Mount the ailerons to the wing with the template at one end. Wing Figure 92.

    57. Wing Figure 92 Aileron template in position

  57. Put the aileron in the neutral position.
  58. Align the 0 degree line on the template with the line on the aileron.
  59. Holding the template stationary move the aileron through its range of -40 degrees to +20 degrees.
  60. If the aileron does not clear the top skin by 1/16" spacers can be used between hinges and rear spar to increase clearance. Wing Figure 93.

    61. Wing Figure 93 Aileron clearance adjustment

  61. Slide a 2" washer (M2W) onto the torque tube root end.
  62. Measure the distance from the end of the torque tube to the 2" washer.
  63. Cut a sleeve (CC-54) from 2 1/4" x .120" tube (W-150) using the measurement from step 234).
  64. Deburr the end of the torque tube and sleeve.
  65. Slide sleeve (CC-54) over the end of the tube and an end plug (EL-31) into tube.
  66. Ensure that the torque tube is pulled rootward and the 2" sleeve (CC-54) is against the 2" washer (M2W), then drill eight equally spaced holes through the sleeve, tube and plug 1/2" from the end. This tube has a circumference of 18cm, which is one hole every 2.25cm. Drill out to #30 first and then #11 Wing Figure 94.

    67. Wing Figure 94 Torque tube inboard end plug

  67. Disassemble and deburr.
  68. Make a push-pull tube (CC-82) from 3/4" x .035 tubing (CC-51) as in Wing Figure 95.

    69. Wing Figure 95 Aileron push pull tube

  69. Attach push-pull tube (CC-82) to the control horn (CC-43) with an AN4-11A bolt, AN970-4 washer and an AN365-428 fiber nut. Wing Figure 96.

    70. Wing Figure 96 Push pull tube to control horn

  70. With the flaperons in neutral position attach the other end of the push-pull tube (CC-82) to the flaperons with an AN4-13A bolt, AN970-4 washer and AN365-428 fiber nut. Wing Figure 97.

    71. Wing Figure 97 push pull tube to ailerons

  71. Ensure flaperon still has 20 degrees up deflection and 40 degrees down deflection.
  72. Set flaperon so it is at 20 degrees up deflection.
  73. Bolt, (allowing some movement) a control horn (CC-43) to the end plug at the root end of the torque tube. Securely cleco together all parts fitted in step 239). Adjust control horn (CC-43) so that it clears the bottom of the wing by 1/2". Wing Figure 98.

    74. Wing Figure 98Control horn inboard position

  74. Drill eight #11 holes through control horn into the end plug. Wing Figure 99.

    75. Wing Figure 99 Control horn inboard drilling

  75. Remove and deburr parts.
  76. With suitable 1/4" hardware, temporarily bolt another control horn (CC-43) onto the root control horn. Wing Figure 100.

    77. Wing Figure 100 Control horn inboard duplication

  77. Drill a #11 hole through both parts approximately 1/2" from the end hole. Store the drilled horn. Deburr parts, chromate mating surfaces and rivet previously fitted root control horn and associated parts with sixteen 3/16" x 3/8" stainless steel rivets (RV-5606). Wing Figure 101

    78. Wing Figure 101 Control horn inboard riveting

  78. Remove push-pull tube (CC-82) and control horn, (drilled in step 248), CC-43) and set aside for later use.
  79. At this time the wing, if inspected can be closed up. Be sure all holes are drilled to the correct size and deburred. Chromate all mating surfaces that have not been done. Be sure all hardware is torque to the proper specs