Step 1: Make six trim tab clamping  blocks out of a 3/4" thick wood board using the dimensions in Figure 1. 

Step 2: Make six trim tab ribs from the three PVC-750 x 2 x 4.5 foam blocks supplied in the kit. Using the templates found on the last page of this section, cut out the ribs as you did with the trailing edge ribs earlier

Step 3: Mask the inside surface of the E-919 Trim Tab Skin around the locations for the trim tab Ribs. The rib locations can be found on Page (-17, Figure 3. Scuff the skin in the location of the ribs with 150 grit aluminum oxide sandpaper, clean the scuffed area with acetone until all sanding residue is removed, then remove the masking.

Step 4: Complete the trailing edge bend on the E-919 Trim Tab Skin using the home-made brake shown in Section 5., Figures 5-5 & 5-7. 

Cleco the E-920 Trim Tab Spar to the skins as shown in Figure 3, then, using one of the trim tab clamp blocks, made in step 1, check that the entire length of the skin is bent fully and uniformly with no ballooning or puckering

Step 5: Bend the two tabs on both ends of the E-919 (E-1019 right side) Trim Tab Skins. To accomplish this, make two wood wedges having the same geometry as the cut out in the trim tab clamp blocks made in Step 1 (you may be able to use the wedges cut from the clamp blocks if they are in good shape). Radius the edges a 1/32" to prevent cracking the skin.

As shown in Figure 4, position the wedges parallel to, but offset 1/32" from, the straight portion of the skin forward and aft of the tab. Place double sticky-back tape between the wedges and skin, to prevent the wedges form sliding then clamp the trim tab skin and two wedges to a workshop bench as shown in Figure 5.

Begin bending the tab around the wedge by hand using a small, wood block, then finish the end by tapping back and forth along the tab with a flush rivet set in a rivet gun that has been turned down low. The tab with the two holes lays on top of the other.

Step 1: Once again cleco the E-920 Trim Spar to the E-919 Trim Tab Skin. Slip the clamp blocks over both ends of the skin to hold the skin in the proper shape as shown in Figure 1. Match Drill the holes of the inner tabs using a #30 drill.

Step 2: Remove the clamp blocks, then mark the lower surface of the skin at the web of the E-920 Trim Tab Spar for the 15 degree bend shown in figure 1. Remove the spar, make the bend, then replace the spar.

Step 3: Remove the shaded area, shown in Figure 2, from the E-917 & -918 Trim Tab Horns. Make sure to keep the edge distance of the remaining hole when trimming

Step 4: Cleco the E-917 & -918 Trim Tab Horns to the E-919 Trim Tab Skin and to the bottom flange of the E-920 Trim Tab Spar as shown in Figure 2. Final-Drill the holes common to the horns, skins and spar using a #40 drill.

Step 5: Disassemble and deburr all parts

Step 6: Dimple all the holes in the E-919 Trim Tab Skin and the #40 holes which were drilled in step 3) in the E-917 & -918 Trim Tab Horns.

Dimple the holes in the bottom flange of the E-920 Trim Tab Spar.

 Machine countersink the holes in the top flange to leave a smooth surface for mounting the trim tab hinge.

Step 9: Apply tank sealant to all of the mating surfaces of each foam, trim tab rib (no more than 1/32" thick) and put them in place inside the trim tab.

Slip the three clamp blocks onto the trim tab, directly over the ribs, and push them tight.

Step 10:  Rivet the bent tabs on the sides of the trim tabs using the blind rivets shown on Page 9-19, Figure 2.

Set the trim tabs away for a few days to allow the sealant to cure

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