Chapter Log

Step 0 - Materials
Status: Completed 
Est Time: 0.00, Actual: 0.00
Est Cost: $ 1305.40, Actual: $ 6147.22
Date Completed: 09/01/2005

For lack of a better place, I'm logging materials here. I had previously ordered materials one chapter at a time, combining where I could afford to do so. As I'm ramping up my productivity, I've just purchased all of the materials for the remaining chapters, except electrical or engine components, brakes, canopy, or seat belts. I'll be ordering all of those shortly.

To save time later, I cut all of the aluminum hardpoints at the same time, and labeled them so they'd be ready when I needed them.

Update:
During a conversation on another topic, Dennis Oelmann mentioned to me that he had a wing and spar pair, completed and already match-drilled to one another. The price was reasonable and I had the money, so I jumped at the chance to save some build time here. Dennis does excellent work, often peel-plying and vacuum-bagging even very large parts. His parts are often ready to finish when they arrive.

I still have the half-finished left wing, and the cores cut and waiting to lay up for the right wing. Occasionally in some pictures in this log you'll see them - the left wing is hanging on ropes in the hangar, and the right wing cores are on top of the wall cabinets. Hopefully one day they'll get some use.

Step 1 - Building the Wing Jigs
Status: Completed 
Est Time: 4.00, Actual: 8.00
Est Cost: $ 0.00, Actual: $ 0.00
Date Completed: 11/02/2005

This took a bit longer than I thought, and they aren't exactly beautiful, but I think it was worth the extra trouble. I made my jigs out of 3/4" plywood, which provides a lot of stiffness. However, the thickness makes it awkward to get the wings in, which are really at an angle to the jigs. To solve that problem, I chamfered the inside edges of the jigs so the actual contact surface of each jig is only 3/8" or so.

Step 2 - Setting up the Jigs
Status: Completed 
Est Time: 0.00, Actual: 6.50
Est Cost: $ 0.00, Actual: $ 0.00
Date Completed: 11/05/2005

Step 3 - Cutting Foam Cores
Status: Completed 
Est Time: 0.00, Actual: 17.00
Est Cost: $ 0.00, Actual: $ 0.00
Date Completed: 11/04/2005

John Slade is up for the week helping me with the complex wing steps. That's not to say this chapter can't be done alone, but extra help sure makes the time go faster, especially if that help has made a wing him/herself. Hot-wiring does really take two people. I've heard of people cutting solo, using supports and other assistants to help hold the hot-wire cutting. I think it would be very challenging to get good, consistent cuts that way.

We had some extra setup time because I saved some money. Wicks had a fire sale on foam, which normally runs $21 to $41 depending on block size. The stuff I bought was only $4.50 per block, a huge cost reduction, but it was only available in the smaller (7x14x41) size. To make up the difference, I bought 25 blocks, and we're cutting blocks to add to the ends of others. It adds time, and time is indeed valuable, but I'm happy we did this. The extra work with the blocks gave me time to adjust to block layout and hot-wiring, so I was much more prepared (and had gotten used to handling the saw) when it came time to do an actual airfoil cut. It wasn't really much extra work - just squaring the ends, and joining blocks to make them longer. The 3M 77 spray adhesive worked great here. Note to others - make sure your block faces are very clean when you join them. Even a slight amount of dust can prevent a good adhesive bond.

Step 4 - Core Assembly and Web Layup
Status: Completed 
Est Time: 0.00, Actual: 14.25
Est Cost: $ 0.00, Actual: $ 0.00
Date Completed: 11/07/2005

Step is complete for left wing

This took a little more time for the left wing than John Slade (who was up for the week helping me build the wings) and I expected. Mainly this was because of a few small alignment issues setting up the cores, but we wanted to get things perfect. Also, I caused us to take longer in the squeegee step by putting on too much epoxy by getting over-eager with my "dump and run" layup method. Still, the left wing joint is beautiful. We'll see if I can do the right wing just as well.

When you cut the W18 cover plates that go over the wing attach bolt access holes, note that cutting per plans is unlikely to produce a good fit. A better way is to cut the plates slightly oversized, make the bend, then get the plates into position and scribe them to cut off the excess for a perfect fit. You only use an extra half inch of aluminum this way, and they look much better.

Also, a comment on Alodine. I've had mixed success with this, so I thought I'd pass along a few tips that generally produce better results. The most important thing to know is that the qality of the Alodine step is almost entirely controlled by the cleanliness of the part. The Alumiprep can produce a part that looks clean, but once you alodine you see fingerprints and such left over. By then, it's too late to do anything, and that spot won't take the Alodine very well.

To make sure the parts are perfectly clean, first use some MEK or other cleaner to remove any micro or epoxy contamination that might be on the piece from setting it on a workbench, against a curing work piece while measuring, etc. The key to understanding what's happening is knowing what these chemicals actually do. Alumiprep will NOT remove this stuff - it's an acid, not a solvent. It's designed to react with corrosion and remove it, and etch off any other surface problems. But it only works against aluminum-related problems. So, after removing any epoxy issues, wash with clean water and a strong detergent to remove skin oils. Alumiprep will not remove all oils, just a few of them.

Next, know that the effectiveness of the reaction will be controlled by heat. You're suposed to dilute the Alumiprep, which is fine, but do it with warm water, not cold. You'll get a better reaction. Use a disposable brush to remove as much surface crap as possible. Then comes the key - use an abrasive Scotch Brite pad. (Use one without soap in it - Harbor Freight sells cheap but usable pads.) Get down into any scratches, which you ought to have - you did rough up the faces before glassing, right?

Finally, when Alodining, use a brush to make sure you have good coverage of the chemical. Some of the initial reaction may produce free converted material in a thin barrier liquid layer of used-up reagent on top of the piece. A brush will move this aside and allow the reaction to finish on the piece itself. I use small disposable acid brushes for this - you can get 36-packs cheaply.

Don't forget to radius the corners of the wing attach hard points to match the foam, before installing them! And don't forget LWA2 and LWA3, which are described in Chapter 14. I missed mine for the left wing, and will fix this when it comes time to glass the bottom.

Step 5 - Bottom Spar Cap
Status: Completed 
Est Time: 0.00, Actual: 15.50
Est Cost: $ 0.00, Actual: $ 0.00
Date Completed: 11/14/2005

11/14/2005:
A few comments.

First, box sealing tape is the WRONG choice for this area. The open pores of the foam allow epoxy to creep underneath the tape, where it sticks to the adhesive. This makes it very difficult to remove later. I don't have a great solution to this, actually, but at the very least use a thicker tape, like duct tape. Box tape tears when you take it off, and makes a godawful mess. I didn't want to leave any of it around, so it made for a lot of tedious sanding

Second, add a squeegee step an hour or so after you finish the layup. I had my spar cap on the left wing squeegeed perfectly level with the top of the trough. The next day, though, I discovered it had uncompressed slightly. It wasn't a huge rise, less than 1/16", but it made for a heck of a lot of sanding to bring it back to level. Better slightly low than slightly high - it's a lot easier to fill a slight outside skin depression with micro than to fair the entire wing into this area, and if you squeegee low, at least all the spar cap tape is there, and you aren't sanding any off.

Finally, PROTECT YOURSELF. I've sanded quite a bit so far, as you might imagine, but I never had a problem with it. I generally used the Fein, and was doing small areas at a time, either to rough up prior to a layup or to remove epoxy drips and the like. I'd get an itch or two, but was pretty careful, so it was never more than a minor irritation.

This time, whoah! I used the belt sander, and while "less than 1/16" doesn't sound like much, multiply it by the length of the spar cap, and you have a lot of fibers being removed. This stuff is VICIOUS. I probably would have been fine sanding - I got some dust on my hands, but not much worse than that. I wear a shop apron to protect my shirt and pants, and haven't had any issues until now. This spar cap stuff is MEAN when it's sanded. It produces long individual fibers that stick to everything. I was fine until I went to vacuum. The static from the vacuum pulled the stuff all the way up onto my arm. I've been itching all day, and probably will again tomorrow. Use protection!

11/16/2005 (2 hours):
More careful cleanup.

11/17/2005 (4 hours):
I got a little fed up with making aluminum parts piecemeal - sanding, alodining, etc. were all slowing me down because of the time involved in breaking the tools and chemicals out and putting them back. I thus spent some time making all of the aluminum parts I needed for the next month or so, which include the four seat belt brackets for Chapter 8, and all remaining LWA1-LWA6 pieces (three were already made). They're now alodined and ready to go. Hopefully this will save me some time in future steps.

The only thing I didn't make was the right wing's LWA18 cover plates, because I found it was easier to make these a little oversized and trim after trial fitting them. Getting the bend just right on the very end of the piece is tricky, so I just make it an inch further in, mark the exact edge where it meets the wing surface, and trim to that point. No point making and alodining something I'm just going to cut up...

Step 6 - Bottom Skin
Status: Completed 
Est Time: 0.00, Actual: 7.50
Est Cost: $ 0.00, Actual: $ 0.00
Date Completed: 11/18/2005

11/17/2005 (2 hours):
Today I finished prepping the bottom of the left wing for skinning. Hopefully I can get this done tomorrow. I made the channel for the flox corner around the wing attach bolt recess, and vacuumed the surface one more time for good measure, this time with my hand and arm encased in plastic to protect it from the loose fibers. I also installed the peel ply strips on the trailing edge and aileron cut line.

I used a slightly different method for this than called for in the plans. I tried small brads, but they dimpled the peel ply, and the plans specifically state that it must lay flat. I would have used staples, but I only had a few left and didn't want to run to the hardware store just for this. Instead, I put down small dabs of epoxy every 6" or so along the strips, let it soak in, and gave it a good stipple and wipe-down. I ended up with perfectly flat strips of peel ply. The only negative is that you have to wait a day for the epoxy to cure or the peel ply will come right off when you lay out the cloth, but that worked fine for my schedule.

11/18/2005 (5.5 hours):
Today I did some of my best work. Ever.

I started by installing plastic curtain rod covers to line the conduit hole, and a NAV antenna about midway down the wing. I had intended to do these steps yesterday to reduce the layup time, but forgot. I then micro'd the foam. In the future, I'll pre-fill low spots (like the electrical conduit hotwire entry slot) a day ahead of time, and allow to cure. That would make this step a bit faster, since micro takes time to settle into deep slots.

I then laid out all of my glass, both layers at once. Laying out one ply at a time is fine if you like 8-hour layups, but I'd like to fly some day. MGS wets out two layers of glass just as well as one. So, I got all of my cloth laid out perfectly as my first step. I then mixed LOTS of epoxy and wet out the entire surface, squeegeeing lightly to spread it around. I used a brush to touch up spots, especially around the LE and TE, and the 4" section over the shear web.

Once I had the glass fully wet out, I squeegeed lightly to remove the worst of the excess. I then peel plied the entire wing, and laid out my plastic sheeting. Finally, I very carefully squeegeed, using the hair dryer. I first worked along the spar cap, then from the spar cap to the LE and TE. I spent the most time on this step, making sure I was getting very consistent results so I won't have any thick (high) or thin (low) spots.

The hair dryer really makes or breaks the process of squeegeeing through the plastic. Yes, it helps liquify the epoxy again, but it also does something more important - it lets the plastic stretch evenly. This lets the plastic deal with compound curves without bunching up.

For the curious, yes, I DID use my "dump and run" technique. Large, flat surfaces like the wing really benefit from this method. All this means is mixing very large cups of epoxy, and dumping it in a stream across a convenient relatively flat spot (like the spar cap area). You then squeegee lightly to spread it around in a thin layer, and move on to your next cup. The epoxy will wet out the cloth on its own. This produces some waste (I removed about 1.5 cup's worth during the squeegee stage, about 10 squirts) but you can do large layups like the wing VERY quickly. My time broke out as follows:

1 hour - Install conduit and NAV antenna
1 hour - Micro foam (next time pre-fill holes and let cure, would save time)
30 minutes - Lay out cloth, scissor trim.
1 hour - Wet out with epoxy
30 minutes - Lay out peel ply, stipple to mostly wet out, lay out plastic
1 hour - Squeegee

These are estimates. I think I actually spent more like 45 minutes wetting out, and 1.25 hours squeegeeing, but the numbers should be fairly close. In any case, I'm confident that if I come prepared with antennae already installed, and the slot pre-filled with cured dry micro, I can do the right wing's bottom skin in 3 hours using this technique. We'll see.

The best part of this whole process is that I no longer have any fear of large layups. It used to be a race to wet out and stipple before the entire thing started to gel, and it took a lot of stippling. That's hard on my hands and wrists - I have arthritis. Now, I hardly stipple at all. I only use one for touching up dry spots before squeegeeing, and painting vertical surfaces.

Step 7 - Top Spar Cap
Status: Completed 
Est Time: 0.00, Actual: 6.50
Est Cost: $ 0.00, Actual: $ 0.00
Date Completed: 00/00/0000

11/21/2005 (6.5 hours):
Next week I'll be going on vacation. I'm trying to get one wing glassed before I go, so today I prepped the top spar cap channel for glassing (1 hour) and came back to the office late to do the job (5.5 hours). It was quite an ordeal. It has three more layers than the bottom cap, but the channel doesn't APPEAR to be deeper (it is, it's just unnerving).

Worse still, a number of the threads in my spar cap tape had some type of contaminant, and picking them out and replacing them warped a lot of threads. I spent hours getting everything to lay flat and straight, and when I was done, no matter how hard I squeegeed, I still couldn't get all of the fibers to lay below the channel edges. I'll have some sanding work to do once the layup cures. Sigh.

I think in the future that I won't squeegee directly on the spar cap tape. I did this initially to press the fibers into the layers below, and to bring up excess epoxy. The problem is, it shifts the fibers around quite a bit, and makes the job MUCH harder.

It seems like my magic number is 3 - that's how many layers of tape I can successfully wet out at a time. I'll pre-cut a few 5" strips of plastic to lay in the channel. I'll lay down three layers of tape, get the center wet and lay down a bead of epoxy along the channel, then lay down the plastic. I'll squeegee through that, then lift it to lay down the next few layers. I think this will work better and shift the fibers around less. You definitely want to remove excess epoxy as you go. Otherwise it all ends up at the bottom, and you have a hell of a time getting the tape below the edges of the channel.

Step 8 - Top Skin
Status: Completed 
Est Time: 0.00, Actual: 12.00
Est Cost: $ 0.00, Actual: $ 0.00
Date Completed: 11/25/2005

I plan on installing the hidden rudder belhorns, and a kind fellow builder was nice enough to send me a digital copy of the plans while I waited for mine to arrive in the mail. The only part I needed from those for now was the routing of the rudder cable conduit, which is pretty straightforward - you just run it straight from the entrance location in the wing root to 1.2" in from the trailing edge at WL169. It should come just to the corner of the aileron cutout without actually touching it.

11/23/2005 (4.5 hours):
To prepare for glassing the top skin, I installed the rudder cable conduit and cleaned up the leading and trailing edges. I also cut the notch for the flox corner around the attach bolt access hole. Finally, I sanded the spar cap flush with the top of the wing. I definitely need to get a new belt sander - this took 3.5 hours to do with my piece of trash. The spar cap wasn't bad, just a little proud in spots.

11/25/2005 (5.5 hours):
This step was fairly straightforward, just time-consuming. I took a little longer wetting out the glass than when I did the bottom, because I had to use the brush a lot more. "Dump and run" isn't well suited to steep curves or vertical surfaces, and the leading edge is much more curved on the top than the bottom (naturally). Anyway, no surprises - micro, fabric, epoxy, squeegee, peel ply, plastic, and squeegee with hair dryer.

I clamped an aluminum straight-edge on the trailing edge. The extrusion John Slade and I bought when he was here didn't work out - it got covered with epoxy and I didn't have time to clean it off completely. I bought some replacements, just right-angle aluminum extrusion. I used spring clamps and clothespins to hold them onto the trailing edge and keep it perfectly straight. Should do the trick.

12/6/2005 (2 hours):
I had neglected to install all of the reinforcing layups, so today I took care of those. These included the BID triangle at the outboard edge, the two UNI pieces near the outboard attach bolt, and the three UNI strips over the inboard attach bolt and onto the top of the wing. I also installed the two 2-ply UNI strips that make a "V" from the outboard attach bolt onto the top of the wing. These are actually from step 9, but since I was here it made sense to just do them all at the same time.

Step 9 - Wing Ribs
Status: Completed 
Est Time: 0.00, Actual: 5.00
Est Cost: $ 0.00, Actual: $ 0.00
Date Completed: 00/00/0000

12/7/2005 (5 hours):
Removing the 0.7" of foam took a little longer than I expected. I don't know if there's a better way to do this, but I just used a Dremel cutting wheel, and carefully etched out the foam. It took two passes to get the final depth, but otherwise was fairly straightforward.

Removing the foam for the inboard rib didn't take longer than I expected - I expected it to take a long time, and it did. I had to re-read the plans and diagrams about 12 times to get it all figured out. In the process, I discovered that on my "make the aluminum parts" day I forgot to make the LWA7 pieces, so I made those and prepped/alodined them. Since nearly all of these parts are 2" wide, I've been cutting them out of some 2" bar stock. Hopefully I won't need a huge length of 2" bar stock later, or I'll have to re-order. This is a lot faster than cutting individual pieces out of sheets, since one dimension is already cut for you. You just cut the pieces to length.

Step 10 - Ailerons
Status: Completed 
Est Time: 0.00, Actual: 9.00
Est Cost: $ 0.00, Actual: $ 0.00
Date Completed: 00/00/0000

I haven't taken very good notes of my progress each day, but I HAVE made a lot of progress. I produced the aileron, mounted it, and arranged the controls. I didn't do a great job of hinge placement on the left wing, so I'll try to be more careful on the right. As it is, everything moves smoothly, but I had to jimmy things a lot to get it all working perfectly.

Step 11 - Controls
Status: Completed 
Est Time: 0.00, Actual: 7.00
Est Cost: $ 0.00, Actual: $ 0.00
Date Completed: 00/00/0000

12/23/2005:
Not great notes here, either, but the job got done. This entry is a placeholder for the items I haven't done. I didn't finish this step because I intend to install spherical bearings for the aileron torque tube, and I don't have them yet. I used an FMN10 temporarily to test things out, but I didn't set the final position of things because I don't have the spherical bearings quite yet. Here's what I have left to do for the left wing:

1. Install the spherical bearing for the torque tube.
2. Adjust the CS127 brackets to their final positions.
3. Fill a small air gap under the bracket shoulders with flox.

I also have not jigged the wing to the spar, obviously, because I haven't finished the right wing. Oh, and I haven't made the spar. =)

Step 12 - Attachment, Wing to Center Spar
Status: Completed 
Est Time: 0.00, Actual: 0.00
Est Cost: $ 0.00, Actual: $ 0.00
Date Completed: 04/01/2006

Because I bought my wings and spar together from Dennis Oelmann, he match-drilled them for me. Attaching them is thus a piece of cake. That's a fair bit of tedious work saved!

OK, I actually spent a very long time on this step today, but for me it was a culmination of a LOT of past work that's been lying around the shop, just waiting to be used. Here's what I did today:

1. Installed elevators in canard. The pins are a little stiff from some micro stuck in there, so I didn't drive them home - I'll pull and clean them, then do that next time.
2. Installed canard in fuselage. I didn't bolt it in, since it will probably come out again shortly, but at least I can finish hooking up the controls.
3. Installed mains in fuselage - this should be the final installation, unless finishing requires something weird. I hope it is. The studs were VERY firm going in, and even with my slide hammer it could be an all-day job getting them out again. I'd rather not.
4. Deployed nose gear. Doesn't sound like that big of a deal, but now I can roll the plane around, for the very first time!
5. Installed wings. I used a shop crane to help with this step, and WOW. WOW. If I had known how useful this would be I would have bought one on the first day I started the build!

So all in all, the "plane" is more or less "together". I have a huge list of little junk to work on, mostly finishing various things that couldn't be finished until it was at this stage - rigging the last of the controls, getting the electrical and antennae wired up, installing and trimming all the fairings and other finishing items, doing the actual finishing, fixing the canopy hinges, etc. Oh, and I sort of need an engine and some instruments! But you can definitely see it coming together now!