Fuselage - Cabin

2007-09-09 - Finish F-795 flap push rods. (3.5 Hrs).

After yesterday's screw-up I decided that I needed a better set of taps and dies. I buy a lot of Harbor Freight tools, because they are cheap. As long as you don't need precision, they are usually good enough, but a tap and die is a precision tool, and the HF stuff is just not up to snuff. At least, I'm hoping that is why I screwed-up so bad yesterday. I'd hate to admit that I'm just not that good at turning a wrench anymore. We'll see.

I stopped by Sears and picked-up a new set of taps and dies. I didn't get the most expensive set and I didn't get the cheapest set. This was $69. I don't remember the price of the HF set, probably $20-$30. Hopefully, this will do the trick.
This just "feels" better. No binding, tube is not getting hot, and it feels like it is actually cutting.
Ok, which one would you use? Hint: the one with the rod ends was done with a tap from the new tap and die set.

BTW, the Sears tap table said the correct drill for a 1/4-28 tap is #3, just like Van said, so I went with #3.

So, what is the difference between the HF and Craftsman taps? Craftsman on the left, HF on the right. HF has a tiny tap handle, that holds the tap by screwing in one of the handles. This keeps loosening no matter how tight you make it. Craftsman wins the tap handle comparison.

Hard to see, but the taper on the Craftsman tap carries through the first few threads. The HF tap only has a taper on the tip. This makes it harder to get the tap straight on the HF tap. The Craftsman tap is 4 fluted, and the HF tap has 3 flutes. Finally, the Craftsman is sharper. No question, the Sears tools are just plain better.

BTW, compared to the tools that we used in the Air Force, the Craftsman tools would be considered cheap.

All done. Yeah, one rod is a little shorter. The plans say 4 7/8", so I cut the first rod to 4 7/8". After filing the end to remove the saw marks, the first rod was 4 3/4", so I cut the second rod to just under 5". You'd think I would learn by now.

BTW, I wonder where the other two CM4-4M rod ends are. There were only 2 in the bottle I found them in. Never mind, I found them, they were in a bottle labeled "Flap Hardware".

Lower rod end attached to the flap. Just need to go topside and insert the rod. BTW, I had to drill out the hole in the FL-706B plate here. The flap attach HW would not fit. Should have done this when I built the flaps.
This is going to take a little cutting ...
but we already knew that.
I was hot and tired, and I didn't want to start hacking on this hole until I was a little more rested, but I just couldn't resist using a uni-bit to open up this hole a little. Looks like we need to cut FWD a little, then into the side of the fuse.
Ok, this is where I decided to stop before things go bad.
Have to finish this a few weeks from now, since I have to be in Santa Fe next week.