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fhpe77's blog
Posted by fhpe77 | Nov 16, 2013 @ 11:14 PM | 4,827 Views
Last weekend I managed to forget to snap a picture of my Fireworks 5. I like to take a picture of new planes just before the maiden flight just in case it all goes wrong and it gets totaled. So I went out today for my second session and managed to snap the attached picture. It was cold, damp, and overcast today. Not too much in the way of lift going on. I had one 4 minute flight but that bubble petered out quickly. It was, however, time well spent. I got to tweak the radio programming a little, adding some more down elevator to landing mode. Expo was added to the elevator and ailerons in thermal and cruise modes as I forgot to do this during the initial programming. I also wanted to run the battery down and see how much time I can get out of it. After an hour and a half the Turnigy Nano 300mAh, 35-70C 2-cell battery was at 7.4V. Pretty impressive for such a small battery. The last throw of the day is where it got interesting. I threw it hard and upon release I heard a cracking sound. In a state of panic I make a quick transition to level flight then brought it back for a landing. Initially the wing was suspect but then I observed the forward wing mounting nutsert was partially pulled out of the fuselage. Good grief! I thought this thing was supposed to be strong. The nutsert was pressed back in to it's original location and thin CA was wicked in around it. It now appears to be solid as a rock. We'll just see about that tomorrow morning when I head back to the field for another session.
Posted by fhpe77 | Nov 09, 2013 @ 09:08 PM | 2,804 Views
The light at the end of the tunnel was shining brightly yesterday. With 4-6 mph winds in the forecast for Saturday morning, I was busting to get the Fireworks 5 ready. It was a throwing blade, balancing, and radio programming away from being flown. So I was on a mission starting on Friday morning to get it finished and flown.

I carefully milled a slot in the left wingtip with a tiny Dremel ball mill. A combination of measuring and marking coupled with expert eyeballing resulted in a well located throwing blade. Once the blade was oriented in accordance with the instructions, top forward when viewed from the side and leading edge cambered toward the fuselage when viewed from above, a couple of drops of thin CA were used to lock it into place. The throwing blade has an airfoil shape and does not fill the entire slot. The resulting voids need to be filled and a fillet is required between both upper and lower blade to wing surface interfaces. My old friend Devcon 30 minute epoxy to the rescue! To achieve proper fillet shape retention while curing, I added enough West System 406 colloidal silica to create a medium-thick slurry of goo that was subsequently directed into the voids with a tooth pick. The tooth pick was used again to build up and shape the fillet on each side of the wingtip.

As built, it weighs in at 258g. An additional 10g was needed to get it to balance between 65 and 70mm from the leading edge of the wing. For the mathematically challenged, this...Continue Reading
Posted by fhpe77 | Nov 09, 2013 @ 06:27 PM | 2,707 Views
Non adjustable control rods...ACK! What a foreign concept. I'm a Dubro EZ connector kind of guy. Since I never tried this sort of thing before I was kinda looking forward to it. It actually worked out quite well. I built the aileron lever ends first, installed them, then measured and cut the carbon tube at the servo horn end. With the radio fired up and the servos centered I glued in the L-bends, resulting in a perfectly sized custom control rod. While the instructions called for thin CA, I opted for medium CA for the extra (read not instant) cure time. The keeper wire is 0.028" and is held to the carbon control rod with heat shrink tubing and backed up with thin CA.

Hmm, a rudder pull-spring. Yet another new technique. Per the instructions, I bent the spring wire so the span was 25mm and the legs were 15mm. It was easy to poke the wire spring into the balsa stab and rudder. Finally, the spring was secured with some thin CA, which also served to harden the insertion points.

The tail to fuselage interface was secured with thin CA and backed up with some carbon tow and more thin CA. This has effectively made the fuselage and tail one piece.

Kevlar wire was used for the elevator and rudder pulls. This stuff can be twisted and glued with thin CA or knotted and CA'd. I used all the above techniques to secure the Kevlar wire. Silicon grease was applied to any sections of the wire if they were at risk of being accidentally bonded with CA.
Posted by fhpe77 | Nov 04, 2013 @ 07:03 PM | 2,779 Views
Ten pounds of stuff in a five pound bag. That's what it was like getting the electronics into that fuselage. It took me a couple of evenings of scheming, test fitting, and massaging until I determined the best layout. Excess wire was eliminated by modifying the length of the servo wires. Mounting the regulator in the rear leaves plenty of room for the battery in the nose and allows it to be easily removed for charging. This position also allows the regulator's voltage indicator light to be visible through the canopy. The inside of the fuselage was lightly scuffed with some 150 grit sandpaper and with the servos already attached, the radio board was glued in with medium CA. I didn't trust myself with epoxy around those servos. That was a mess waiting to happen.

Thanks to A Main Hobbies, I was able to source the elusive UHU Por conact adhesive necessary for hinging the rudder. That stuff was hard to find, what is it made out of unicorn tears or something? Per the instructions, some UHU Por was spread on the rudder and v-stab and allowed to set up for 20 minutes. Two small pieces of scotch tape were applied to lock in the correct position of the rudder then the entire hinge line was covered with a ten inch piece of scotch tape. Finally the rudder was notched out and the kit supplied control horn was glued in with medium CA. Please note that my plane is being set up for a right handed thrower. The launch peg will be installed in the left wingtip the tape hinge is on the left side of the rudder, and the rudder horn is on the right side. Lefty configuration would be just the opposite of this.
Posted by fhpe77 | Oct 14, 2013 @ 08:56 PM | 3,466 Views
My son managed to shoot some videos of my Gambler AG. The first is two launches were in dead air. Those flights weren't too long. The second video shows the Gambler AG in a light thermal. That flight was around three minutes but the video didn't start recording until I was in it for a minute or so.

Two Short Gambler AG Flights (1 min 50 sec)



...Continue Reading
Posted by fhpe77 | Oct 14, 2013 @ 08:48 PM | 3,430 Views
Here's what I have for electronics. The battery is a Turnigy nano-tech 2S, 300mAh. The regulator appears to be a PLD-BAC-55C which has both visual and audio battery status indicators. The original owner provided the recommended servos. Hitec HS-45HB's for the ailerons and elevator and a Dymond D4.7 for the rudder. According to the rcgroups thread for this model, the HS-45HB may have some issues with the elevator return spring. Feeling the tension of the spring with my hands, I have to agree. So I replaced the elevator servo with a Hyperion DS-09SCD. It's taller than the HS-45HB and will require some care in placement and horn length to get it to fit and not rub the hatch. The receiver is an Airtronics RX-500. It's perfect for this application because I have exactly five things to plug into it. There is no way it will fit with the case so I removed it and gave it the heat shrink treatment. The hole in the heat shrink is for access to the bind button and status LED. It is taking some time getting all this stuff to fit into the fuselage but in the end I expect the same level of serviceability that I demand from all of my airplanes. It's not worth a hill of beans if servos can't be easily swapped.
Posted by fhpe77 | Oct 14, 2013 @ 08:19 PM | 3,484 Views
Just about a year ago I folded the foam core/bagged wing of my competition style DLG for the second time. I imagine it could be repaired again at the cost or even more weight. The day of it's last flight it was tipping the scales at just under 12 ounces. That's just too darn heavy. It was given to me because it was old and outdated, but the donor was certain that it would be good for me to learn how to setup and fly four servo DLG's. He was right. I loved that thing. I flew it for about a year and a half and got pretty good at it.

Upon it's demise I started looking at what it would cost to replace it with a modern design. One of the models I looked at was the PCM Fireworks 5 Flow. It looked to be a pretty innovative design with outstanding performance potential. Then I looked at the price. Way out of my budget! It was getting to the point that I was considering one of the Chinese knock-offs but I just couldn't bring myself to do that. So I figured that I would just build me a Gambler AG and be happy with that. And I am happy with Gambler but it does have some limitations.

One day last month, at the South Jersey Golden Eagles club field, there was a gentleman that was asking some of the other sailplane pilots if they'd be interested in a DLG kit that he was looking to sell. He was pointed in my direction a proceeded to make me a offer I couldn't refuse. He had a Fireworks 5 Flow kit for sale, including servos, battery, and regulator. The price was, well lets just say it was really, really good. Apparently he had injured his throwing elbow at work and didn't want to aggravate it by throwing a DLG. He was simply looking to get back some of the money he spent on it so he could invest in a less physically demanding model. His loss was my gain. For once I was in the right place at the right time. I never thought I'd be able to own this level of model and I'm still waiting to wake up and find out it was a dream.
Posted by fhpe77 | Oct 02, 2013 @ 09:41 PM | 3,389 Views
I wound up with a slightly tail heavy airplane, which was to be expected with the light weight battery. In order to get it to balance at 3/8" behind the spar I needed to add 0.35 ounces to the nose. I simply taped a nickle and a penny to the battery which got the balance perfect. This brought the AUW from 6.15oz to 6.5oz.

The maiden flight was performed last Friday evening and consisted of a gentle toss into the 5mph wind. A couple of clicks elevator and rudder trim got it flying straight. The next toss was a gentle discus launch. Subsequent launches increased in force but the gambler could take it. Very impressive for such a light weight airplane. I was easily hitting 70 - 80 feet launches after a while. I also noticed that a 6.5 ounce DLG does not beat up your body as much as an 11 ounce competition style ship. I flew for 45 minutes until sunset and the battery came down at 8.1V. It looks like up to two hours of fun are possible.

The evening maiden was nice but lift was scarce. So I went out at 1:30PM on Sunday afternoon which was gloriously 75 deg. F with 6 mph winds. There were tons of low level cumulus clouds, indicating a nice thermal day. I wasn't disappointed. The Gambler was spec'd out repeatedly for an hour before I decided to call it quits.

In conclusion, I highly recommend this airplane. The build was quick (for me) and reasonably challenging. Flight performance is excellent for what it is and the Gambler will stay aloft for quite a while bouncing from bubble to bubble. Put this thing into a moderate thermal and it climbs like mad! Good stuff.
Posted by fhpe77 | Oct 02, 2013 @ 09:11 PM | 3,456 Views
Dymond D47, 4.7g servos were chosen for this application. They've proven themselves to me in the Wind Dancer V-tail. Torque output is outstanding for such a small servo, centering is good, and the gear slop is tolerable.

I deviated from the servo mounting technique outlined in Allan's great instructions. I just can't bring myself to glue servos in with CA. Also, horizontal mounting would make the Dubro EZ connector set screws inaccessible. Thinking outside the box, I chose an inverted vertical mounting scheme. The servos are screwed to balsa mounting blocks. An additional benefit to the mounting scheme is that the push rods no longer have to make any radical turns to meet the servo horns. This reduces the load on the servos and extends battery life.

The battery is a 30g Rhino 360mAh, two cell lipo. It fits with plenty of room. The voltage is reduced to 5V with a tiny 1A Blue Arrow linear regulator. I've used this configuration is four servo DLG and would regularly get nearly an hour of flying out of it.

The receiver is an Airtronics RX-600 that I had laying around from my now deceased molded DLG. The regulator is simply stuck to the top of the receiver with double sided tape.
Posted by fhpe77 | Oct 02, 2013 @ 08:45 PM | 3,430 Views
Wing covering consists of more white Solite and yet another appearance of transparent blue Solite. I know what you're thinking. "Didn't this guy learn his lesson when he covered his Wind Dancer with white and light blue?" Well the answer to that is apparently no. Actually I had the covering left over from the Wind Dancer. It's already paid for, so why not use it. The color scheme is not that bad. I just have to be on top of my game if the plane starts to spec out. Certain angles and lighting conditions can make it disappear.
Posted by fhpe77 | Oct 02, 2013 @ 08:37 PM | 3,422 Views
Carbon tow was laminated to the tail components. I opted for some additional reinforcement as the increase in stiffness seems to offset the minor weight gain. For the sake of durability, some tow was added to the lower leading edge of the vertical stabilizer. That seems to harden it up nicely.

I chose to cover these parts with white Solite prior to gluing them to the boom. This just seemed to make the most sense. The control surfaces where hinged with scotch tape. In order to shape the balsa horizontal stabilizer pylon mount to conform to the boom, sand paper was taped to the boom and it was used as sanding bar. This resulted in the correct concave shape. Note that I managed to not take a picture of the pylon...doh! Prior to gluing, the covering was cut away where the Kevlar reinforcements attach.
Posted by fhpe77 | Oct 02, 2013 @ 08:22 PM | 3,256 Views
Been slacking on blog posts as of late. The building however, has proceeded to conclusion. Since I like to see thumbnails in my posts, the next five entries will show the completion of my Gambler AG.

The pod was covered with white Monokote. Still loves me some covering here. I find it to be quite rewarding. Getting it to adhere to the fiberglass was a none issue.
Posted by fhpe77 | Aug 18, 2013 @ 05:27 PM | 4,530 Views
Wow! The Naval Air Station Wildwood Aviation Museum is awesome! My wife had to pry me out of there. I did manage to ask an employee if they were hiring. They were not. I love the smell of old machinery...oil, paint, and metal. Yummy. The airplanes that stand out in my mind are the Stearman, Mig 15, T-28, F-14, F-16 and F-5E. The Mig-15 was quite a bit smaller than I expected. I bet that thing was quite the hot rod back in the day. Anyway, I have attached many pictures for your viewing pleasure. ...Continue Reading
Posted by fhpe77 | Aug 18, 2013 @ 11:15 AM | 4,170 Views
What happen to the summer? Last time I checked it was June. Now I'm sitting here in mid-August on my summer vacation. We're spending the week in Wildwood Crest, NJ. The condo we rented has an ocean view that's just lovely. It's cloudy today, with a significant chance of rain. But I don't really care. I actually enjoy walking on the beach when it's cloudy. But that's not what we are doing today. Instead we will be visiting the Naval Air Station Wildwood Aviation Museum. Lots of pictures are to follow...

The picture of the Kloud Queen was taken August 2, the morning of the SAM12 Old-Timer Summer Meet. Of course I set the camera down after taking the picture and promptly forgot to bring it with me. However, my bud Warren managed to get a hold of some pictures taken by Mike Salvador. They can be seen here:

http://www.rcgroups.com/forums/showthread.php?t=1974054

It was certainly a good day for my shiny-new Kloud Queen. I managed to take first place in Brown Junior LER and second place in Electric LMR. The removable power setup performed well and I was able to make the conversion in less than ten minutes, which was good because it was nearing 1:30 pm and times had to be in to the score keeper by 2:00. I spent the morning making the Brown Junior flights, which left little time to make the electric flights. Another interesting fact was my Kloud Queen was not the only Kloud Queen there. Another pilot, whose name escapes me at the moment, had one as well. It...Continue Reading
Posted by fhpe77 | Jul 27, 2013 @ 12:14 PM | 4,748 Views
Performing a build in the summer is proving to be challenging. Not that the actual build is difficult, but finding the time to do so is where the challenge lies. I'm even having trouble fitting in some flying time between work, lawn mowing, car washing, honey-do list, etc. It might be time to adjust my priorities. If I could just eliminate work and that honey-do list I would be good to go.

Anyway, the wing is coming along nicely. While the parts are laser cut, some light sanding is necessary to get the ribs to fit the spar and trailing edge properly. A nail file stolen obtained from my wife made short work of this process. Thin CA was used to tack everything together then I backed it up with some medium CA at the leading edge dowel to rib interface. The completed structures seem flimsy but I suspect that they will stiffen up significantly with the application of the D-tube sheeting. We'll see how that goes...
Posted by fhpe77 | Jul 06, 2013 @ 10:35 AM | 4,956 Views
Allan's instructions are correct, properly glassing only adds three grams to the pod. The weight went from 24 grams to 27 grams. Laminating two small washers between pieces of scrap 1/16" balsa added another gram, bringing the total up to 28 grams. Finally, hatches reinforced and tabbed with 1/32" plywood and embedded with 3/16" diameter neo-magnets brings the total up to 30 grams. So far, so good.
Posted by fhpe77 | Jul 02, 2013 @ 08:55 PM | 5,001 Views
Playing with dangerous chemicals on the kitchen table. Always fun stuff. My wife, bless her little heart, is pretty cool with my model building shenanigans. She never complains about the epoxy smell. The automotive paint I used on the Wind Dancer pod was another story. Heck, I even did that in the garage and I still got to hear about how the whole house smelled like an auto body shop.

Glassing the Gambler AG pod was uneventful. First I fitted the fiberglass cloth dry to see how it would lay. Next, excess cloth was cut off to make it easier to work with. The now smaller rectangle of cloth was placed on wax paper and sprayed with at light misting of 3M 77 spray adhesive. Finally, the sticky cloth was applied to the pod and strategic cuts were made to get it to fit the contours of the nose and rear. This was the first time I tried the adhesive method and it worked great. Kind of reminded me of applying covering but without the iron.

I did spend some time thinking the epoxy process through from start to finish. Protect the working surface. Prepare paper towels. Pour some denatured alcohol into a cup. Don't drink it. Break out the resin and hardener. Get the chemical resistant gloves. Get the credit card squeegee, mixing stick, and mixing cup. Once everything was on the table I started to envision how I would be applying the epoxy with my right hand while holding onto the boom with my left hand. It was doable but I needed a way to support the...Continue Reading
Posted by fhpe77 | Jul 01, 2013 @ 09:14 PM | 4,658 Views
Next up, the Wright Brothers RC Gambler AG. I've been wanting to build one of these for a couple of years. My particular kit was graciously donated by Allen Wright to the 2013 CAMS/Polecat/Soaring Circuits Open Soar. I was fortunate enough to win it in the drawing that Denny held at the end of day one. Thanks Allen!

This kit is impressive. The plans are top notch, printed on thick paper. It even comes with instructions that contain color photos! Yummy laser cut boards are complimented by a complete set of controls hardware, nice CF tail boom, and some exotic fabrics. Pretty much everything needed to build a Gambler AG except the covering, CA glue, and epoxies.

So far the build has been straight forward. I did deviate from the instructions by mixing up a slurry of 30-minute epoxy and colloidal silica to further reinforce the tail boom to pod interface. This will add a small amount of weight but hopefully I managed to offset it somewhat by sanding the tail boom to remove it's epoxy ridges. The added peace of mind will give me the confidence to throw this plane hard.
Posted by fhpe77 | Jun 11, 2013 @ 10:09 PM | 5,199 Views
I finally got around to balancing and flying the Brown Junior. It started last Saturday evening at around 9:00 PM. I got the electric setup assembled as I have been flying it and reviewed where it balanced. It seemed to balance around 3/8" ahead of the spar and I have been flying it this way with it coming down with no trim in the elevator. It flies nice and well mannered yet signals lift and does not tend porpoise in this configuration.

The goal was to get the same performance with the Brown Junior.

The electric setup weighs 63.8 oz and is presently flying with an additional 2 oz for a total of 65.8 oz. This results in a wing loading of 11.4 oz/ft^2.

The Brown Junior setup weighs less at 58.2 oz. Simple arithmetic reveals that I needed to add 7.6 oz of lead to get to the flying weight of the electric configuration. So I added 8 oz and checked the balance. Wow! now it seemed like it wanted to balance closer 1" ahead of the spar. Thinking that would reduce some the the nice floaty feel, I whittled down the lead until it weighed 4.2 oz. That made it balance at 1/4" ahead of the spar. I figured that this would be safe to fly so I made the weights permanent with some 30 minute epoxy.

The Brown Junior setup now weighs 62.4 oz (less fuel) which results in a wing loading of 10.8 oz/ft^2.

Next it was time to check that the ignition was working so with it powered I used my finger to complete the circuit between the HT lead and the spark...Continue Reading
Posted by fhpe77 | Apr 11, 2013 @ 08:44 PM | 5,998 Views
So where is a 1938 Kloud Queen supposed to balance? Seems like a reasonable question to me. The plans do not provide any clues. I guess the cg must be located using some old school free-flight rule of thumb or something. So I went with what I know. Conventional non-lifting stab and flat bottomed airfoil wisdom would indicate a distance 33% the cord length from the leading edge. Well that's easy, 12" cord wing places the cg at 4" from the leading edge. Hmm seems tail heavy at 4" and seems to want to balance on the spar, which is located at 5" from the leading edge. So I grab some conveniently available weight in the form of some rubber drink coasters that weigh 2 oz each. It took four coasters placed on the nose to get it to balance at 4". Having to add 8 oz of lead to my already 3.99 pound airplane did not thrill me. Now of course this is the electric setup and with the necessary 4-cell 2600 mAh battery it's 5.6 oz heavier than the ignition engine setup. So I figured the ignition setup would require an additional 11.5 oz of lead to get the correct cg! Not cool. After some discussions with Leadchucker I decided to add less than half the necessary weight. It was all very scientific. I told Leadchucker of the required 8 oz nose lead and he said "I'd try it with half of that.". Now where did I put the stick-on lead weights? The package I found was already open and half the weights were gone, leaving me with only 3 oz. So 3...Continue Reading