Installing the upgrade...some tips, tricks and a few snafus

Ok, so I got the "upgrade" kit Monday. Already had started to drill things apart and had it ready so I could inventory and start locating and installing the kit. A few things I have to say first off, well packed, marked and nice quality of the metal and hardware. But, after studying the drawings a bit I was a little confused, to say the least, on what part went where. I went to school and got an ASS degree in CADD and have been an A&P for 20 yrs. I currently work at a FAA certified Repair station and have made many drawings for 2 STCs and multiple repairs. I could be me but I found the drawings a little confusing and VERY busy. Also, the parts are listed in a "description" form to the left and then in the assembly drawing and details they are referred to as a part number. (same thing with the guide) My thoughts and consistent and use a p/n ONLY or description ONLY not a mix. Also, WAY TOO MUCH information on ONE (1) sheet! HOLY COW! break it up a little! use one sheet for one item or task. That way it isn't so overwhelming and someone doesn't miss anything. I spend more time try to figure out the drawing and what it is trying to tell me. Also you need to include things like, "DO NOT INSTALL RIVETS IN THESE LOCATIONS" for the area where the doubler is going along the spar cap. "MARK EDGE OF PART TO ENSURE PROPER EDGE DISTANCE" "#3 RIB ANGLE WILL BE SHORT E.D. IF OUTSIDE ANGLE IS MARKED IN SAME MANNER AS #1 & #2 RIB" "USE A CHIP CHASER/BURR HOOK TO REMOVE CHIPS FROM BETWEEN SANDWICHED MATERIALS BEFORE RIVETING" "USE A DRILL BUSHING TO ENSURE PERPENDICULARITY IS MAINTAINED WHEN DRILLING THROUGH THE SPAR AND CAP" do not say in guide "locate angles on #3 and #4 ribs (if wing has 4 ribs) the same as #1 & #2" when you don't give the materials to do rib #4.

This is where the angle wouldn't have worked like the drawing showed. I placed the angle on the inbd side rather than the outbd side. Where would the rivets go?

Note I am short E.D. for a #5 rivet on rib #3. Because the doubler is not in this location and if you space the rivet on the outbd angle the same as the rest it will cause you to short yourself E.D. on this part. (these are #30 holes)

use a doubler like this to make sure you tie at least 2 ribs together. this will ensure that the ribs stay positioned for future reassembly.

noticed I marked the edge of the angle prior to drilling. This will ensure I will have plenty of E.D. on the angle.

drilling using a "drill cup" or bushing WILL SAVE you a Headache! there is ALOT of material to drill through and even I as long as I have done this CAN NOT drill a straight hole BY HAND through this much material. Start out with a #30 and then use a step drill if you have one.

My remody for fixing the short E.D. problem. Off-set drill 4 more holes. I later step the 4 hole to #21 and install #4 rivets and #5 rivets, solid that is.

I removed the doubler and installed #5 solids through this angle to make sure there wouldn't be any shop heads against the spar web.

This is a Cosdill Deburr or an "in-n-out" works great to deburr those hard to reach places.

Between the spar web and inner cap.

Use draw clecos where you can. They keep things tighter. MAKE SURE you clean all the swarf (drill shavings) out from inbetween the mating surfaces!!!!!!! Well that is it for now.....Until tomorrow!

Well it isn't exactly tomorrow! HAHAHA!

I finally got back to doing some more on the 601XL. Today I finished the trailing edge angles and the bottom skin angles.

The trailedge the only thing I need to comment on is the hole for the pushrod. Take the time and make it alittle more on the stretched side and clean all the edges nicely so there is no stress risers.

I did this because the pushrod had been hitting the dege of the hole and 'sawing at it'. I also toosed in a few more rivets.

As for the bracket "U" channel, when I removed the rivets, they almost fell out and I was alittle amazed that the bellcrank bracket had been installed with the pop rivets. So, not being the trusting soul I am in pop rivets, I installed the bellcrank supports in with solid MS20470AD5-5 rivets. Also, I noticed that when I tightened the nylok nut for the bellcrank, it got REALLY stiff. So, I will be replacing the undrilled bolt for a drilled boly and a castle nut with a cotter pin. Remember people, if you have a plane the rotates about a point and there isn't a Heimes joint or some sort-of bushing to keep the plane from becoming bound when the hardware is tightened, you need to stick a drilled bolt in with a castle nut so you can safety the bolt and nut from coming loose.

The other thing I did that wasn't in the drawings, is I tied the angles on the bottom skin to the adjacent rib. Why would you not? I could have taken the time and made a clip to tie it into the outbd rib, but I figured what I did was better than not doing it at all. All the airplanes I have ever worked on the stringers were tied into the ribs or bulkheads....why didn't this get done? ????

And for the most outbd angle I tied it to the rib and the wingtip.

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Comment by A David NIxon on March 15, 2010 at 6:46pm
My kit is finally installed after 4 weeks of getting to it. I am just finishing up the re-rigging of the ailerons. I have push-pull rods. Regarding the construction manual provided, I put it away after my first look thru. It just didn't help me at all. You have to watch the drawings closely though. For instance, on sheet # 6-ZU-1 they tell you about the wing upgrades, parts etc. However, on sheet # 6-ZU-3 they tell you to double up the spar rivet line thru the the newly installed extrusion (top) and thru the bottom spar angle out to Rib #5. I missed this the first three times thru the drawings. Also, on sheet 6-ZU-1, 6-ZU-1-2 Airframe bolts, it calls for an AN3-6A bolt at the end of 6-ZU-1-1 extrusion angle. This was missed on an upgrade in progress that I had seen recently. So, I guess it is best to read, re-read and then re-read again these sheets. Unfortunately, the factory has not been much help with these items. All I can say is that they must be inundated right now. I am a big boy and can work it out.... eventually.
Comment by Timothy R Mix on February 11, 2010 at 10:29am
I wasn't 100% pleased either but they do go through it step by step. There are a few things that they don't mention soon enough though. They need to mention that when installing the rear spar angle, you need to drill out the first top rivet in every rib so that way the angle is tight against the spar. Also, to back drill each rib FIRST before laying out the rivets going through the spar. I also drilled through the angle and the aileron bellcrank doubler together rather than laying it out on the doubler then back drilling. I will post a few more picture later.
Comment by Sam Birchill on February 10, 2010 at 8:22pm
Thanks for the info in the "Drill Cup". I just got my kit by UPS today and I am not real happy with the "manual". It sure would have been nice if they would have had an exploded view of the parts. There photo guide is so close up that I am having trouble with figuring out where everything goes. I already put aileron balancers on courtesy of Andy Elliott's design. I tried them out before this "kit" came to be and they worked great.

Comment by Timothy R Mix on February 7, 2010 at 10:54pm
try "the yard store",5662.html
or ATS, Brown Tools, US Tool (USATCO)
Those are a few options.
Hope this helps.
Comment by Sam Birchill on February 7, 2010 at 10:28pm

Where did you get the "drill cup"?
Comment by Timothy R Mix on February 4, 2010 at 7:57pm
Thanks for the feedback Jake! I moved the 'blog' to the forum also. I didn't know if everyone could see 'my blog', if they can oh well just a double post :P. I added a couple of pics with some extra cogsdills and how to make a burr hook, so hopefully that will help.

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