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Posted by rab | Apr 15, 2010 @ 08:25 PM | 5,935 Views
A friend of mine at work uses the adage 'what is the stupidest thing it could possibly be, start there' when trouble shooting, I find I should use it more often than I do. I've not been too satisfied with my GeeBee QED; it has had a tendency to pitch down at frequent but irregular intervals. Not severely down but it happens often enough to make you feel like you are fighting to keep the plane in the air. Since this is an EPP plane I was thinking the issue was due to the wings flexing sometimes. For some reason today I decided to try moving the CG a bit farther forward. So I added two quarters and two nickels to the cowling. And voila the plane is now stable.

The little Miles M20 is now flying well. Something about this plane, probably it's size, makes it of interest to the local crows. Twice now they have flown over to harass it.

- Allen
Posted by rab | Mar 30, 2010 @ 12:10 AM | 5,165 Views
Assembly & Diss-assembly.

The metal head for the HK450 does not seem like any major improvement to me.

The Miles M20 is coming together now. Looks like it will weigh in at about 4.5 oz with a 20 in wing span. So I'm guessing this will not be real slow. The empty glide tests were I checked the CG placement were fabulous, so if i have the flight controls right it should fly well. I'll post a picture of it sometime soon. I'll also have to post a picture of my DR1 again now that it has a pilot.

Sunday I made myself the opportunity to put a new fuse on my Infineon. I Probably can and will patch this one back together again, but I'm thinking it is about time to fix the fixes.

- Allen
Posted by rab | Mar 05, 2010 @ 11:35 PM | 4,775 Views
Progress on repairs. The HK 450 is back together. I'll need a few more flights on it to get it tuned. Repairs to the DR1 are near done, and I am working on it's pilot again, it'll be done again in a few more days. So I a far enough along that I am planning my next build(s). I am planning a Miles M20 and an Ambrossini SS4. I'm planning 18/20 inch wings hoping to get the weight at 4oz. I've just finished the M20 drawing so the next step is printing.

- Allen
Posted by rab | Feb 19, 2010 @ 10:08 PM | 4,851 Views
Yeah I had to change the colors a little. Allen
Posted by rab | Jan 24, 2010 @ 11:31 PM | 4,659 Views
It is that time of year. I've mostly finished putting the HK450 back together. But while setting up the collective I noticed that the pitch servo has a gear issue, it jumps a bit at one spot.

I decided to turn a holiday gift certificate into a parkzone su26. I've flown it twice, it does what I wanted it to. I hear some beeping I'll have to search for what that means, and since I broke a prop on the first flight I am sure I'll need more. I have it in my head that I want to change it's colors, but it would be foolish to add any measurable weight...

I've made a superslofly 28. I made it with 9mm 1.9 weight EPP. I am thinking that lighter would be to my liking so I'll see what I can do.

My poor DR1 has been languishing with broken landing gear, I'm feeling an urge to get it back together. I am also thinking that I should build a replacement using the techniques from my QED build and being a bit more careful about weight. Because again I'd like to see it able to slow down a little more.

- Allen
Posted by rab | Jan 01, 2010 @ 03:03 PM | 4,089 Views
So I've read plenty of advice that suggests we should store lipos at about 3.8v per cell. I decided to try that to see how it would work out. Not. There is an unanticipated issue with non-anticipated flying opportunities. Today's weather is better for flying than I expected, so here I sit with nothing charged and by the time I get things charged it will be too late for the trek to the field . - Allen
Posted by rab | Dec 28, 2009 @ 12:36 AM | 4,645 Views
I was able to get out to the field this afternoon. Was very surprised to have the field to myself, especially as the conditions were good for this time of year.

Flew the Infineon, Viggen ,QED , and HK450. Was the first flight for this QED, it needs a few tweaks but is very promising . Got behind or lost orientation on the HK450 and executed a firm inverted landing, so I'll be replacing the whole head assembly .

- Allen
Posted by rab | Sep 28, 2009 @ 10:03 PM | 4,134 Views
I had the field to myself yesterday morning. It had rained over night and there was still bit of mist or fog early in the morning, nothing serious.

- Allen
Posted by rab | Sep 24, 2009 @ 10:52 PM | 4,206 Views
So another dZee was built, it's been flown a few times. I'm happy with it.

It is made of EPP. You can see the skewers that damp out the wing flutter which happen on exit of a fast dive.

The flying weight is about 8oz with a 2s700mah lipo. The motor is a blue wonder 1300 with an 8060 GWS dd prop.

And credit where it is due - this plane is really only a very minor variation on GPW's Foam-EZ...Canard Sportif' the dimensions on this plane mostly match the dimensions on the Foam-EZ.

Posted by rab | Sep 20, 2009 @ 09:41 PM | 4,043 Views
I am planning to start another Gee Bee QED build.

I've a couple of choices to make.
1) Material, EPP or EPS?
2) Wing airfoil, under-camber or symmetrical?

A few of the related parameters. I have and would both 3mm and 5mm sheets of either foam. The wing span will be about 30inches the flying weight should be 8 to 10 ounces. So I am not expecting a high wing loading. And I am not asking for a high speed. I'm planning to use a blue wonder motor and a 700mah lipo.

What would you choose for this project?

- Allen
Posted by rab | Sep 17, 2009 @ 10:36 PM | 4,105 Views
So a few more photos to post. The field shot is from a weekend this August before I got the HK450 back together.

And I do have the HK450 back together, I've been flying it as much as I can. Working on being able to be comfortable hovering side in. Progress is happening, but it feels slow. At my current rate I might be comfortable with a race track pattern by next year.

And a couple more photos if my DR1. The DR1 is sorted out now, I'm mostly flying it on some 2s 700mah lipos, pulling something like 300mah off the battery in about 10 minutes flying. I'm currently working on a pilot to put in the plane because it just looks wrong to me to see it cruising around without one.

- Allen
Posted by rab | Aug 02, 2009 @ 10:47 PM | 3,925 Views
So I decided to fix the HK450 by getting another one. Put the new one together and finished the set up yesterday. But I had pitch reversed, so right after lift off it drifted forward a little and when I pulled the stick back a little I nosed it right into the ground. The blades popped right off, the main rotor holder sheared off right where the flybar went through it. Today I did an inventory of parts from the first one and the second one and realized I had just enough good parts to put it back together. Then when I had it all back together I found that the main shaft had bent. So it will be a few more days till it is ready to go.

Balancing and the DR1, yes balancing the blade made a huge difference. I also adjusted the wheels so they don't wobble so bad too. I can fly it on 2S or 3S. At the moment 2S is what I'm preferring - the plane looks right going slow.

While I'm waiting for the heli shaft I think I'll go back and rebuild the d'Zee. I did not put that one together well, it is falling apart.

After that it'll be another QED. Although I've been looking at the Miles M20 too. We'll see, it'll be next week at the earliest before I will start that.

- Allen
Posted by rab | Jul 08, 2009 @ 11:13 PM | 3,935 Views
I totaled my heli this morning. I've been trying to get to fly my heli in a race track or even just back and forth. The HK450 is much more challenging than the CX2 since I can't ignore roll. So when I got behind and could not get reoriented in time I ended up driving it into the ground hard. I have a bent frame, ruined blades, and most of the upper part of the head is bent or broken. I could fix it and upgrade the broken bits. But it will cost less to buy another kit and turn what can be salvaged from the crashed frame into spare parts.

My DR1 is bugging me. The bad bearing in the rewound BW is getting worse and the vibrations are now definitely affecting performance. But I do have another BW on the work bench now for rewinding, hopefully this one will not develop a bad bearing.

And on the note of bad vibrations. I think I have to pay more attention to balancing props. I have two planes that have minor vibrations that I suspect are due to their props.

I've finally got some video of the Viggen, of course it is currently 450mb of .mov file for 3 minutes of flying so some editing will have to happen before I post it here.

- Allen
Posted by rab | Jun 04, 2009 @ 09:59 PM | 4,038 Views
So I could not get the dZee canard to turn. As happens the issue was mostly not were I first thought. These two changes fixed it:
1 - moved the CG slightly forward
2 - took all the reflex off the main wing

- Allen
Posted by rab | May 31, 2009 @ 11:21 PM | 4,044 Views
You can see the Viggen's nose is all fixed, it's been flying very well. In front you can see my new toy. The heli seems to be working pretty well, but it is going to be some time before I can fly it very well.

- Allen
Posted by rab | May 04, 2009 @ 10:43 PM | 4,567 Views
The Viggen's shattered nose back has been put back together, there were not too many pieces. There was one fragment missing, I patched in a new bit of depron there. Then since the lower side of the nose was getting abraded by landings I put some light weight fiber glass cloth on the nose with thinned white glue.

- Allen
Posted by rab | May 03, 2009 @ 02:36 PM | 3,794 Views
So on the dZee I put fins on the end of the main wing, turns out that is too much of a good thing. I could not get it to turn. I had enough differential in the ailerons that it should have turned. I found I could put a little bend in one fin or the other and get the plane to make a flat turn in one direction or the other depending on the bend. Since I really don't want to put a fourth servo on this plane I am going to move the fin inboard were it was on previous instances of this plane.

The nose of the Viggen has glued back together easy enough, it was only missing one smallish fragment. I think I am going to put some light weight fg on the bottom of the nose for abrasion resistance. The pink foam nose cone was more abraded then I thought. Paint matching will be challenging if not impossible.

I've been researching heli basics as I have the parts for my HK450 on the way.

- Allen
Posted by rab | Apr 26, 2009 @ 11:56 PM | 3,697 Views
I've pranged the DR1 again, entered a spin unexpectedly. I've been happy with the power system, a rewound blue wonder pulls about 16 ounces of thrust and uses about 250ma in 10 minutes. But I've not been happy with the amount of noise this plane generates. Somehow at the best flying speeds the plane gets an unpleasant growl going. I might try to address that when I rebuild this. I also thought it would slow down better than it does.

I flew a rebuilt dZee today, rebuilt in EPP this time. Flew nice and slow. But I tried to just use a single spar at about 25% of the cord, that resulted in a rather large flutter when the plane reached about 80% throttle. I'll add a spar as far to the rear as practical and another at the leading edge. If that does not seem to work then I may replace the main wing with some blue core.

I've been somewhat frustrated with my blade cx2. Saturday I figured out that I've made the cg too far forward. I'll have to rework how the gear is mounted to pull the cg back. I would like to figure out how to make a boom mount so that I can replace the stock body tail. That way if I move the gyro to the rear I could easily access the gyro's to pots. I'll have to pay close attention to the bottom rotor drive too, it seems like the bottom rotor spins a little slower that the upper rotor.

I now have ordered the last parts I should need to finish the HC450 I bought back in January.

- Allen
Posted by rab | Mar 29, 2009 @ 11:35 PM | 3,467 Views
My last two weekend's flying have generated some repair work. Two weeks ago snapped my DR1 in half and rearranged the interior of my dZee, this weekend I made my Viggen need a nose job.

The DR1 was victim of a bad solder joint I made on a battery connector (it take over a year to fail). Lost power at fifty feet or so then made a graceless cartwheel landing. The fuse snapped in two just behind the wings. The repair was easy and finished the same evening. I've added some paint. I am planning to make a pilot and guns for this one.

The dZee was again my fault - it is too symmetrical- I could not tell if it was right side up or what, in the end I made a one point landing. The battery and motor both migrated forward through the interior structures. I should get to fixing it this week. I'll add a canopy which should fix the visual symmetry issue.

The nose on the viggen was messed up because I did not keep the battery warm, so it hit low voltage cutoff on launch and I was not able to restart it before it nosed in. I am not sure if I will attempt to repair or replace the nose. Either is possible.

- Allen
Posted by rab | Mar 21, 2009 @ 11:44 AM | 2,951 Views
I put this together in four days. I had hoped to fly it at an indoor event, but a friends new baby trumps a new airplane! So no it has not flown yet.

Yes it is a biplane canard, and yes the biplane wings are probably too close together, but I thought it looked good on paper, well QCAD actually but you get the idea. It might be quirky in the air but it should be slow enough that it tolerable anyway.

It is based on/inspired by GPW's FoamEz, a really great flier. It was aimed at (and hit) a wing loading of 3oz/sq ft. The wing span is 24in. I do still have the weight budget to put a canopy and some paint. But I'll do that after I see how it flies, in the mean time I'll go put some paint on that DR1.

- Allen