Page 13 of 160

Re: Cotton Waiex 191 - N191YX

PostPosted: Fri Mar 14, 2014 10:03 pm
by Bryan Cotton
Tonight was a proud night for me as a father. Adam's skills have been really coming along. Saying this, there is still a large difference between the skills you have when you have been doing something for 6 months as compared to decades. The good thing with sheetmetal and rivets, they are forgiving. Drill through 2 pieces of .025 a little off perpendicular, and they will still rivet together fine. Going through the .050 of material there isn't enough time for the hole to get too out of whack. The rivet expands and will make up for some of those sins. This is good, I still make those mistakes sometimes. For a critical bolted fitting, just good enough for rivets and sheetmetal is not really good enough. You need good perpendicularity and roundness of holes. The skills, especially when you have an army of clamps that preclude using a drill press, must be good. You have to feed it perpendicular. You have to not put side load on the drill. The feed is important. Sometimes it is hard to juggle being a father and a builder. The builder in me wants to get down and do everything. I like to build and have spent a lifetime working on the skills. The father in me wants to see my own kids surpass me in all things. My initial thought was a compromise. I figured I would have Adam run the holes to #30, then #21 and I would take over. The last passes are always the most critical. When he was drilling to #30, there was still some sideload on the drill, partly because he was trying to push it through rather than let the drill do the work. So, we talked about it. I coached him on the techniques again. I shot the first #21 hole, showing him the slow feed, and the alignment. Each flute was happily cutting out long spiral chips. On his first #21, he got the feed good, still a little sideload. I explained how the chatter was feedback to him that he was sideloading the bit, rather than trying to run it in straight. I also noticed he tended to hold the drill high each time, and had him make a small correction. When he hit it the first time, and I saw him making that nice pair of spiral chips, we both knew he had it. The drill broke out the other side smoothly and his feed speed didn't even change. A couple more small corrections on a couple more holes and he had it. He had let that drill find its happy place, and in turn found his own happy place. I think this is part of what drives many homebuilders, or craftsmen of any discipline. The feeling of accomplishment of not just doing something well, but really well, is the therapy that brings inner calm and confidence. We didn't get to finish tonight. Tomorrow I'm going to let him take all those holes up to 3/16".

Drilling a #21 hole:
Y fitting 1.jpeg
Y fitting 1.jpeg (127.01 KiB) Viewed 36718 times


Ready to drill slightly undersize - probably 11/64
Y fitting 2.jpeg
Y fitting 2.jpeg (131.65 KiB) Viewed 36718 times


PS Happy Pi day

Re: Cotton Waiex 191 - N191YX

PostPosted: Fri Mar 14, 2014 10:35 pm
by MichaelFarley56
That's a wonderful thing you have going with your son Bryan. Some of my early best memories was helping my father build his homebuilt...that bonding time is very special. I can only hope that, as my 18 month old son gets older, I will be able to have similar experiences with him eventually.

Thank you for sharing this. I'm also very happy to see you're making good progress on the tail spars! The project is looking great. Keep it up!

Re: Cotton Waiex 191 - N191YX

PostPosted: Fri Mar 14, 2014 10:45 pm
by Rynoth
Awesome story, precious stuff.

Re: Cotton Waiex 191 - N191YX

PostPosted: Tue Mar 18, 2014 11:25 pm
by Bryan Cotton
Took a break from doing taxes for therapy. Cut the big hole in the tailcone bottom skin for mixer access.

Re: Cotton Waiex 191 - N191YX

PostPosted: Fri Mar 21, 2014 8:51 pm
by Bryan Cotton
Adam and I clecoed the tailcone together.

Re: Cotton Waiex 191 - N191YX

PostPosted: Sun Mar 23, 2014 11:05 pm
by Bryan Cotton
First trial fit of the belly skin. Found out I need to bend the vertical channel #5's so they are parallel with each other. Somehow I missed that detail.

Re: Cotton Waiex 191 - N191YX

PostPosted: Mon Mar 24, 2014 6:01 pm
by ScottM-Sonex1629
Nice polish on those side skins! Did you find the bottom/belly skin fit okay? Mine needs just a minor amount of trimming in a few areas (less than 1mm) but otherwise fit fine with the pilot holes on the lower cross tie formers.

Re: Cotton Waiex 191 - N191YX

PostPosted: Mon Mar 24, 2014 6:41 pm
by Bryan Cotton
Scott,
I had issues with the #5 crosstie, as I did not have the correct angle bent into the flange. All my other angles were pre-bent and I missed that one. I could flex it back and get the holes to line up, but that is no way to run a railroad. I have the left one drilled off and rebent, and am working on the right one. The edges stick out beyond the side skins a bit, but I will flex those to make it work. If I don't flex them, the longerons are like 1/16" lower than the flange of the crossmembers in some places. Thanks for the compliment!

Re: Cotton Waiex 191 - N191YX

PostPosted: Mon Mar 24, 2014 7:52 pm
by ScottM-Sonex1629
Good point on the flexing. I might try that later. For now I updrilled to 1/8" then removed and stored this skin. Going to leave it off until after all the controls are rigged for access.

P.S. On the #5 vertical channels. I did not Re-bend mine. I connected the upper and lower cross ties with the rear most vertical stab channel and other angles in place and it went together fine. There was slight spring tension in there that didn't seem to make much difference. I admire your desire for perfection though!

Re: Cotton Waiex 191 - N191YX

PostPosted: Thu Mar 27, 2014 6:16 pm
by Bryan Cotton
Reassembly of the tailcone, so we can drill up to #30.