Log Entries for Flaps
Log Entry Date: Oct 16, 2011
Flaps
Flap assembly - ribs and control plates
Laid out the 12 flap ribs 6W1-1 into left-side and right-side sets, carefully noting that the rib flanges face outboard on all but the most outboard rib. Marked the "top" and rib number on each one for matching up inside the flap skin later. Marked the rivet hole centerlines on all flanges.
The inboard left and right ribs (which I identified as #1L and #1R) needed to be slotted in the web to allow the flap actuator pin to engage. The HomebuiltHelp DVD shows a 15 mm slot, but the 650B plans call for 25 mm. I double checked myself three or four times to make sure I wasn't misreading the plans. I placed the flange of each rib against the flat side of my level to measure and mark off the dimensions (40 mm and 84.5 mm) for the 1/4" drilling and the overall slot length. Next, I matched up the two ribs back to back and clamped them together so that the drilling and finishing of the slots could be done simultaneously, making each a mirror image of the other. I drilled three pilot holes across the width of the slot markings, then followed with the 1/4" bit. Using my snips, I clipped out much of the remaining material without distorting the web surface, then I used a flat file to smooth the sides of the slots until they were parallel at a 1/4" wide. Using a round file, I cleaned up the burrs from the drill bit at esch end of the slot.
The two nylon control plates 6W1-3 were stamped from a sheet of nylon, so the edges were burred to some extent. I used a utility knife to clean up the edges before further handling. I measured and marked off the drilling and overall slot size dimensions, then clamped the two plates together similar to my approach with the ribs. I drilled three pilot holes and followed up with the 1/4" drill as before. This time I separated the two pieces and used my utility knife to gradually cut away the remaining material. I fit the bit back into the slots and ran it back and forth to make sure I had a clean 1/4" opening along the slot. Next, I positioned the plates up to the ribs to align the slots. I found that the nylon plate slots were 1.5 mm too short. You can't fix this with additional drilling or a knife blade, but my round rattail file happened to be exactly 1/4" diameter, so I clamped each plate between wood shims in a bench vise and carefully removed the additonal material to reach the necessary 25 mm. The slot came out cleaner after this procedure than it was with the 1/4" drill bit.
Finally, I measured the 8 mm distance at each corner of the plates for the rivet holes. Again, I aligned the plates with the slots in the outside face of the ribs and clamped them together. I drilled #40 holes and cleco'd each corner. Holding the parts up to the light, I could see variations between the nylon and aluminum slots so I used a file again to dress those surfaces for a good match.
This was the end of the prep work for the flaps. Stopped here and cleaned up the bench and floor before proceeding on the flap assemblies.
The inboard left and right ribs (which I identified as #1L and #1R) needed to be slotted in the web to allow the flap actuator pin to engage. The HomebuiltHelp DVD shows a 15 mm slot, but the 650B plans call for 25 mm. I double checked myself three or four times to make sure I wasn't misreading the plans. I placed the flange of each rib against the flat side of my level to measure and mark off the dimensions (40 mm and 84.5 mm) for the 1/4" drilling and the overall slot length. Next, I matched up the two ribs back to back and clamped them together so that the drilling and finishing of the slots could be done simultaneously, making each a mirror image of the other. I drilled three pilot holes across the width of the slot markings, then followed with the 1/4" bit. Using my snips, I clipped out much of the remaining material without distorting the web surface, then I used a flat file to smooth the sides of the slots until they were parallel at a 1/4" wide. Using a round file, I cleaned up the burrs from the drill bit at esch end of the slot.
The two nylon control plates 6W1-3 were stamped from a sheet of nylon, so the edges were burred to some extent. I used a utility knife to clean up the edges before further handling. I measured and marked off the drilling and overall slot size dimensions, then clamped the two plates together similar to my approach with the ribs. I drilled three pilot holes and followed up with the 1/4" drill as before. This time I separated the two pieces and used my utility knife to gradually cut away the remaining material. I fit the bit back into the slots and ran it back and forth to make sure I had a clean 1/4" opening along the slot. Next, I positioned the plates up to the ribs to align the slots. I found that the nylon plate slots were 1.5 mm too short. You can't fix this with additional drilling or a knife blade, but my round rattail file happened to be exactly 1/4" diameter, so I clamped each plate between wood shims in a bench vise and carefully removed the additonal material to reach the necessary 25 mm. The slot came out cleaner after this procedure than it was with the 1/4" drill bit.
Finally, I measured the 8 mm distance at each corner of the plates for the rivet holes. Again, I aligned the plates with the slots in the outside face of the ribs and clamped them together. I drilled #40 holes and cleco'd each corner. Holding the parts up to the light, I could see variations between the nylon and aluminum slots so I used a file again to dress those surfaces for a good match.
This was the end of the prep work for the flaps. Stopped here and cleaned up the bench and floor before proceeding on the flap assemblies.
| Slotted inboard flap ribs |
| Backside of slotted flap ribs |