Car-Tow

I'm starting to feel better about this whole car-launching thing. Here is a picture of an Australian powered Goat on an engine-off flight. From what I can tell, it is essentially tying a rope to the car bumper and attaching that to the tow-bridle of Goat. I read that for a short field, it is proper to have a ground pulley that turns the car to face the glider. This way, the driver can better see the aircraft on launch too. Of course, the driver does not drive directly at the aircraft. Also, I find a slight issue that the glider needs to have a very good sense of where the turn-around is located so the glider doesn't get pulled down. In the desert areas, the pulley isn't used and the vehicle simply drives along a road as far as the glider pilot wants, getting better altitude than if a pulley was used. Still, it sounds pretty cool since I don't know anyone in the DC area yet with a tow plane; suggestions are welcome!

Christmas order

If anyone is still reading, I just put in an order for the aft fuselage (tailboom?) section as an impulse. I had the order prepped sometime over the summer, just didn't have the guts to hit the "order" button. Despite having two other active RC airplane projects going on and the school semester wrapping up, I figure having the raw material makes getting back working on Goat more accessible when I finally get the time again. Yay!

In particular, I'll be receiving material for the vertical tail triangle and lower boom support such that I can join the tail feathers to the fuselage. I'll have material for the anti-twist bracing, as well as picking up several spare parts to finish off specific areas of the nose section. A bucket of rivets will let me finalize the cabanes too. I suppose I probably could have done work on the tail ribs, but aluminum work is more satisfying to me right now.

'least I got this out of the way before Christmas hits and I feel that pinch!

PS: I just found a plastic part company that has free samples ... so we'll see if I can get the end caps on sample!

Cabane happiness

It's growing slowly but surely.

The nose section now has cabanes with all the pieces attached! I added the compression struts to the back of the cabanes using some long rivets and two 1/16" washers. It took a bit of filing to fishmouth the tubes to match both angles and fit to the correct depth. Sort of glad that I'm bolting rather than welding.

A bike trainer stand does a great job of keeping the nose section standing upright while I'm working on it.

The central cabane intersection in progress. The main plate has the proper bolts and associated hardware. The forward cabane strut has the insert and is happily riveted. The aft strut is what needs work next. By the plans, it is about 1/4" shorter than I'd like to see. I have an extra piece of 3/4" x .035" tube that I'll cut long for this replacement piece. I also need to do the insert for it and then all the riveting. I'm out of rivets again.

Yeah I'm out of washers too... 200 washers last time wasn't enough!
I worked a tad on the kingpost too, despite that I can't assemble it on the aircraft inside! I haven't cut the large holes in it to pass through the cable connections.

I have not yet bought the tubes that go over these inner structural piece. I still need to get a vice so I can ovalize the outer housings. I think it will look better with the ovalized tubes dressing up the structural pieces.

So next I'm going to work on the tail ribs back down in North Carolina before coming back to the nose section. I'll then order the rivets, washers, and materials to make the vertical fin (aft fuselage, tail section, whatever you want to call it) so that the nose and tail are connected! That'll be four or five months from now though :-)

Summer cabane

Time has come for another post. Life is changing ... a semester away from moving, a year away from graduating (yet again), a full 20 days until getting married. But Goat still progresses at its own pace.

Just this week, I received an order for a red Nelson Booster seat. It is a tad smaller than I anticipated, so the fit isn't quite exactly right, but the idea is there. I can always make a custom one that fits later when I care, heh. I laced the seat bottom and back with 3mm utility cord from REI. It's in the climbing isles and boasts 400lb strength, so I figure it should hold my butt up just fine. I painstakingly cut and tied each side with one tube removed such that when I pushed it back into place and dropped the bolt in, all the lines are tight. That sucked. The seat back was easier because I could slide the completed web down until it was snug, but getting the spacing right took several tries. I still have yet to cement the loops in place using some ShoeGoo. The seat itself will eventually be laced onto the cord instead of using a temporary loop around the seat back. I must say, it's pretty comfortable. It's no Tempurpedic, but works for me :-)

Also I have been working on getting the cabanes installed. This meant making the temporary center section pieces include ribs connecting the leading and trailing edges. Quite simply, I could not have purchased enough washers. There is a lot of spacing distance to cover to center the ribs, but whatever, washers are cheap. Next time I'll get 2000 instead of just 200. That should cover me :-)

Anyhow, I put the new long $7 ea. AN-42B eye bolts through the spar LE and TE to make the attachment point to the cabanes. A temporary short bolt and then a few pieces of 4-40 steel rod snaked through the test holes and now the cabanes are up by themselves! The nose tube goes up and supports the front of the cabanes just as nicely as can be. I even spent this morning on the forward pieces of the cabanes, so my head actually fits up inside closed structure (okay, I'm short so not actually inside, but it's nearby). This now is the configuration that it will be for flight. Everything else goes behind me (tail, aft fuse, wings). The wings have cables that tie into the tip of the nose, so I suppose those are ahead of me, but that's splitting hairs. The seating arrangement now is fairly close to the flight configuration.

I also bought a new nose section keel piece. This will replace the one with several kinks in the upper radius. I talked with an A&P guy who suggested filling the tube with sand and using a forming jig (which I can make from plywood). I'm hoping this new part will dress up the nose to look a little more professional. I also purchased a length of 3/4" OD tubing to replace a yet-undecided pair of truss members. Nobody likes the crimped 6061-T6, but if I can figure out which crimp everyone hates and make that look reasonable, perhaps they'll stop complaining.

I also need to figure out where to buy plastic tube end inserts like you might find in lawn furniture. You know what I'm talking about, a little plastic black cap that slides into a tube and dresses up the end to prevent snags on the thin wall and make it look solid. Where can I buy 3/4" and 1" ones of those?

Oh I guess I should also mention that I bought a handful of AN-14A bolts that fit better in the cabanes to get rid of the super long ones. Between making these updates and switching out the low-profile nuts for regular ones, the cabanes are looking rather dressed up.

What's next?

I still have some finishing-out work for the cabanes and replacements on the nose, so that's the immediate plan. After that, I'll be back on campus close to the tail sections again. I'll likely work on the ribs for the rudder and the horizontal stab. Figuring out and finishing those out will be a good accomplishment and set me up for the ailerons/flaps later down the road. I'll also take the sheet stock and start cutting out parts for the wing. I don't have all that many little parts to do, so I fear this will go fast enough I'll want to buy tubes again. My next tubing order I want to be the wing spars and tail tubes. This is all that's left for an easy next-step. I take that back, I guess the vertical tail (aka aft fuselage) is only an 8-ft tube, so UPS won't destroy me too badly. That settles it, I'll finish up the tail feathers then order the aft fuselage tubes. That will keep me busy for a while. I can even go so far as doing the elevator and rudder control rigging after attaching to the fuselage. That will be awesome. Yay for something to look forward to!

Semi-Update

Nothing really has happened since the last post except for a move and two trips to move everything to DC. I suppose I have cut out a few more parts, such as the four trailing edge joining pieces and some other miscellaneous pieces. I joined the trailing edge root pieces too and started on the right cabane. I guess I have done a bit. No pictures this post because it's mostly just busy-work to prep for more fun assembly later.

I think the plan of attack is to tackle the last order that includes some hardware to finish off the cabane attachment (AN42B-26A in particular), a few more pieces of 3/4 x 0.035" tubing to serve as ribs and finish off the cabanes, and perhaps even a seat :-)

I don't know what I'll work on after this order is finished being installed because the more I look, the more it looks like the wings or tail section is next, which means about a $500 order and a trip to pick up the material so I don't get eaten for shipping. I figure I'll get all the remaining aluminum at the same time so I don't have to pay for any more shipping, which means I'll be getting the tubes for the tail section as well as a few pieces for things like ribs and wing tips. I wouldn't be surprised to double the price of the order. So much for buying into this piecemeal.

On the other hand, I still have not finished making the rudder or horizontal tail ribs, which I already have all the material for. The composite fabrication I haven't figured out as well as the metalworking (which is not arguably 100% what it should be). As an alternate, I could work on fleshing out the nose section with some part replacement and fleshing out things like pullies. This probably makes more sense to do all at once though. Hm.

Well, maybe I'll have another post this summer with an answer and some actual pictures of some more progress.

Cabanes and a wing section?

I know this is a bad picture, but here are the pieces for the cabanes laid out on the floor. They are a lot bigger than I thought they would be! I don't think I realized the scale of this project, heh!

I should note that in putting these together with the mass of brackets that I have found two more parts that are mis-dimensioned. The top triangle 3/4" OD tube should be 20-7/8" instead of 20-3/4" and the front one I have not measured yet because my remaining tube is too short to fit. Dang. Also, the cabane channel on G4W10 is too narrow; it should be 1-1/4" channel to fit around the 1" OD rear cabane tube.

I also worked on the wing! Well, I'm making a fake center section that will allow me to put the cabanes on the nose section. This shows just 6" little pieces of the spar tubes that represent the whole wing. I likely can also add a rib down just a few inches to make these sections more stable and get the feel of how they go together.

You can see the mass of brackets that are going into these pieces. So far, running on 10 pieces of bracket and still have another 6 flat ones to go. I am out of 3/4" OD tube to make the root rib, so it'll be a while before this really goes on the nose/cabanes. But, it's cool to hold these in my hand and realize how sturdy they are and get a feel of the mass of the root joint. Whew!

Order up!

It's almost sad how little material you get for an order ... I guess I did get several pounds of bolts this go-around, different from before.

This material is enough to finish off the cabanes, make the control stick assembly, and to make a test center-section so I can mount the cabanes and down-tube. After this, I'll be able to sit in my cockpit, wiggle the stick & pedals, and be fully enclosed like the final product will be!

I guess I didn't really pick up more material to clean up the nose section yet. I guess I'll get to that next order, sometime over the summer.

I started out by finishing up some pieces needed for the control stick assembly. This is where the belt sander really turned out to be useful. Such a long cut from sheet left a rough edge that would have taken an hour to file out by hand. Three minutes on the belt sander and the rough edge was super flat and no nicks were to be seen!

I haven't drilled these yet because I'm going to match-drill a bunch of these holes. The end pieces (triangular ones) will get bolted into the first hole and then I'll drill through the other hole to ensure I get a good fit. This also makes sure the holes are parallel between the two sides.

The plans show the final arrangement of the control stick assembly.

I should note, I had to redo two parts from the next page of the plans due to mis-dimensioning. They should be made from 1-1/8" x 1-1/8" angle, not 1-1/8" x 1".

The control stick as it sits in my living room. I still need to put on the aileron connection pieces and bend the (not shown) front mounting piece into a U. That comes when I have time. Oh, you can see here to the lower left the two brackets I had to redo. Bugger parts...

Out!