Project 5 build thread

[alexM]

Ralph and Eric,
A gold mine, thank you.

In other news (there's always other news isn't there?), I got my Oratex order from Germany in less than a week. That includes my fresh adhesive and five more yards of fabric. My iron and heat gun came just a day earlier.

[alexM]

Finally got in another solid build session. Got to my hangar around 9am and used my bench grinder to put the corner radii on all the steel spar doublers.

Next I removed the right wing and set it on the saw horses. It seems like a job you should have help for but I'm getting pretty good at it. Starting on the top side of the aft spar I clamped the outer doubler in place, drilled through the spar with the 3/32" bit, then introduced the inner doubler and got a Cleco in it. I had just got started when my drill battery wore out, so I had to make the trek home to get the others which were charged up. I also stopped and bought some more 3/32" drill bits since the Irwin and Dewalt brands don't seem to make it very far.
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That clamp was only a temporary thing. I replaced it with a set of long nose vice grips with a bunch of tape on the jaws, then drilled and Cleco'd my way inboard with the 3/32". The manual says to turn right around and blow them out to #30 so I obliged.
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As usual the first pair of doublers took almost two hours and the last pair took about 15 minutes. I kept at it until all the doublers on the right wing were in place and drilled up to #30.
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So next step is to deburr everything, clean up the oil I used for drilling and prepare the non-bonding surfaces for 2 part epoxy primer. I called it quits around 4pm since it seemed like a good place to stop for the day. I had a few hangar neighbors stop by to check on the project and of course I had to run out to see a few interesting aircraft that came through. We had a Chinook make a low pass and a radial powered biplane from the late 20s/early 30s (it was too high for me to get a positive ID on but looked like a Fleet).

[alexM]

With two more short sessions I got all the holes drilled for the left wing steel doublers. I needed to run to eastern Washington for a couple of days and didn't want to lose momentum so I removed all of the steel doublers, labeled them all as to where they went and put together a box full of acetone, rags, deburr tools and a can of 2 part epoxy primer - and took it all with me.

I had some time earlier today to prep the parts so I did that. I was super careful not to mix up the pieces (lots of opportunities to do that) and got them all primed on the sides that will not see Hysol and micro balloons. I'm headed back home tonight and have all day tomorrow where job #1 will be to get these bonded/riveted in place.
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[alexM]

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This job is behind me now. Steel doublers are bonded and riveted in all locations and I can still (just barely) get the pins through. I'll run a reamer back through once the Hysol has fully cured. Now I have to see how much filing I need to do in order to get the wings back on the spar carry through structure. There was enough slop for one+ doublers before I started but not enough for both of them. I didn't want to get out a file until this step was done because I didn't know how thick the Hysol/micro balloons would end up.

My other half has to work all day today so I'm headed back to the hangar to drill/rivet/bond the lift strut attach fittings. Given how long it took to do the spar doublers I have no illusion that I'll have all four lift strut attach fittings done today but I'll put a dent in the job.

I still need to cut the relief into the rear spars so the wings can fold and I need to notch the #1 ribs so they'll fit over the doublers and bond those in place. My paper pattern for the spar notches is missing, having been used the the previous builder. I thought of using my scrap wings as a pattern but I'm pretty sure at this point that they removed more material than you're supposed to, so I would rather just ignore them and do it correctly.

I'm curious what others have used to cut those notches. The manual makes a few suggestions including a file but that seems akin to escaping from prison.

[jiott]

A Dremel tool works great for cutting and contouring those notches.

[alexM]

A Dremel tool works great for cutting and contouring those notches.

Thanks Jim. Any suggestion on what widget to chuck up in my Dremel? I've got a box full of various bits and pieces and can't think of any that would do the job.

[alexM]

Today was at least semi productive (no steps backwards which is always a plus). I reviewed the manual prior to getting out the drill and was surprised how fast it went. Well, except for the part where I realized that I would need my 90 degree drill motor which was at home. Half an hour and $6 in bridge toll wasted I was back on track.

I used a sharpie pen to circle the row of holes which would get the long rivets, and put an X over the ones that urge you: "Don't drill!". I had never noticed the "drill later" holes which go in the rear lift strut attach fittings, nor the reference to a second hole in the middle of the forward lift strut attach fitting. There are no dimensions for laying them out, but I get the intent of them so it shouldn't be difficult.

The drilling went very quickly (yay aluminum). I used a fairly coarse 2" scotchbrite wheel on my angle grinder to remove the powder coating from inside the steel fitting. I cleaned the spar up with acetone, which removed all my layout dye and old sharpie marks. Then I traced around the fitting, masked the spar with blue tape and scuffed it up with a red scotchbrite pad. Then I cleaned up everything again with denatured alcohol and mixed up some Hysol with micro balloons.

The only rivet I couldn't reach was the one in between the ears of the steel fitting which had been used for alignment purposes until today.
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There was quite a bit of squeeze out, which I expected, so I was glad I had left the blue tape in place. A nearly dripping wet cloth with alcohol on it cleaned everything up as you see in the image above. The Clecos all went into a cup of acetone as they were removed. I've screwed up before and not been diligent about cleaning them, and have a couple that don't work very well. After a good soak I worked them over and they came out clean.

In order to bond another fitting I would need to run home and get more latex gloves and another 2" disc, which I didn't want to do. So I did the next best thing and drilled up the aft fitting.
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I'm hoping tomorrow allows me to get at least one more bonded/riveted in place.

[Eric Page]

Boy, you've been pounding it out lately. Well done!

[jiott]

Thanks Jim. Any suggestion on what widget to chuck up in my Dremel? I've got a box full of various bits and pieces and can't think of any that would do the job.

I used the cutoff wheel to remove the big pieces, then used the 1/8" carbide side cutting bit to contour to the line.

[alexM]

^Thanks Jim, I'll give that a try.

I decided to get serious about my panel design. I reverse engineered the MGL MX1 and then used the link suggested in another thread to find switches along with their CAD models. I did some more searching and came up with Klixon type circuit breakers, a starter button, and ELT control panel. I had to draw the dimmer knob up from an internet 3 view.

Engraving is a nice touch so of course I got carried away with that. Still very much a work in progress but it is a start.Kitfox N527KF Instrument Panel 4.jpg
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