The day I have dreaded has arrived. Ths morning I made my first major mistake on an aircraft part. I've read accounts of other builders making this same mistake, and swore it wouldn't happen to me... I even devised a strategy to avoid it. But my strategy failed.
I had finished deburring all the horizontal stabilizer parts, and was beginning to dimple the skins. I thought I'd start with the hard parts. I wanted to see how many of the center rib leading edge holes I could dimple with the C-frame table before I had to resort to using the rivet puller and close-quarters set. Other builders had made the mistake of punching unwanted holes when the dimple die came astray of the rivet hole. I thought I'd avoid that mistake by carefully locating the male die into the hole, then pre-loading the female die to sandwich the piece firmly in place before striking with the mallet. Well... it came astray anyway... and I ended up with a punched and dimpled hole just adjacent to the one that should have been dimpled.
I had finished deburring all the horizontal stabilizer parts, and was beginning to dimple the skins. I thought I'd start with the hard parts. I wanted to see how many of the center rib leading edge holes I could dimple with the C-frame table before I had to resort to using the rivet puller and close-quarters set. Other builders had made the mistake of punching unwanted holes when the dimple die came astray of the rivet hole. I thought I'd avoid that mistake by carefully locating the male die into the hole, then pre-loading the female die to sandwich the piece firmly in place before striking with the mallet. Well... it came astray anyway... and I ended up with a punched and dimpled hole just adjacent to the one that should have been dimpled.
Fortunately, this happened on the bottom of the skin, so whatever corrective measures I make won't be glaringly obvious to the appearance of the aircraft. As I see it, I have several choices:
1. I flatten the errant dimple, dimple and rivet the correct hole and leave the error as is... or perhaps fill it with bondo, liquid metal or welding before painting.
2. I leave the errant dimple, dimple the correct hole, drill a corresponding errant hole in the rib, and rivet both holes.
3. Order a new skin, re-drill, deburr and hope the holes match the ribs and spars.
My biggest concern is the proximity of the holes. They're very close together, and I'm sure that complicates the situation. I'm going to do some research online first to see if other builders' errors were similar to mine and what corrective measures they took before deciding on my own plan of action.
Damn. Well, I knew it was coming... and I'm sure there will be more mistakes in my future. Build and learn.
1. I flatten the errant dimple, dimple and rivet the correct hole and leave the error as is... or perhaps fill it with bondo, liquid metal or welding before painting.
2. I leave the errant dimple, dimple the correct hole, drill a corresponding errant hole in the rib, and rivet both holes.
3. Order a new skin, re-drill, deburr and hope the holes match the ribs and spars.
My biggest concern is the proximity of the holes. They're very close together, and I'm sure that complicates the situation. I'm going to do some research online first to see if other builders' errors were similar to mine and what corrective measures they took before deciding on my own plan of action.
Damn. Well, I knew it was coming... and I'm sure there will be more mistakes in my future. Build and learn.
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