speedracerntrixie

My Feedback: (29)

Cores have been cut and there is a bit of work to be done before sheeting can happen. For the upper wing a wing tube socket needs to be installed. The outter panels have to be joined to the inner panels. There is where the next decision has to be made. There are a few ways I can arrange the taper of the wings and I am not certain if there will be any aerodynamic differences between the two options. Originally I was planning on having a leading edge taper only on the inner panels and double taper on the outter panels. However it occurred to me that I could also set up the inner panels to have some sweep that would set the outter panels with leading edge taper only. If I do the sweep option, the stabs would be set to a small amount of sweep as well. Again I'm not sure if there would be any adverse aerodynamic consequence to this or not but IMO it would certainly look cooler. The pics should illustrate the differences.

drac1

My Feedback: (4)

I think sweep gives a bit broader CG range. And I think it looks cooler as well.

speedracerntrixie

My Feedback: (29)

It does make sense about having a larger CG range. I didn't think of that. I guess my brain is stuck on how cool it looks. I had planned on using a Dualsky 6355 DA-12 motor as I have one in my Hydeaway and coupled with the OS 1100 controller works really well but I saw this Hacker at a swap meet this morning and could not get the 50.00 out of my pocket fast enough.

speedracerntrixie

My Feedback: (29)

Spent a couple hours on the wings today. I decided to go with the sweep. Pictures of the first mock up.

kenh3497

Looking good Shawn!!! Are the top and bottom wing identicle? In the photo they look the same but different.

Ken

speedracerntrixie

My Feedback: (29)

Ken, yes they will be the same. They may look a little different in the pictures due to a very slight difference in span right now. The next step is to sheet the bottom wings while making wing tube sleeves. Once the wing tube sleeves are done and installed in the upper wings I can move forward and sheet the top wings. After that I can perfect the transition between the fuselage and the top wings.

Now a question for the masses again. I picked up a Hacker C50 12XL Acro over the weekend. I did a test run today after setting my speed control to 2 poles and 3 degrees timing. I ran it without a prop and noticed that it did run very smoothly but it got much hotter then I would have anticipated. I'm just wondering if this is normal. It go about the same temp as my Dualsky outrunner after a flight.

speedracerntrixie

My Feedback: (29)

First wing panel is in the bag. My process on this one is quite simple. Once the core is kissed with a little 120 grit it is cleaned very well. The wing sheeting has been seam taped together. I don't like to glue them together as that leads to ridges. For this one panel I mixed up 60 grams of laminating resin and spread just enough on the sheeting to give them a bit of a sheen. The sheeting was placed on the cores and then placed in the shucks with 2 mil plastic between the sheeting and shucks. There is 1/4" press board glued to the outside surface of each shuck to help with maintaining consistent pressure on the shucks. The same shucks will be used for all cores to maintain consistency. After a 12 hour cure, the next core will get done.

speedracerntrixie

My Feedback: (29)

I'm quite happy today. Got the first wing panel out of the bag and am very pleased with the results. Without any other work other then to remove the masking tape that held the seams the wing weighs 145 grams. I have also been working on refining my wing socket process and feel I have some forward progress. Could still use some work but resulted in some useable parts. How about 5 grams for a socket that is still 2" too long? I have also been working on composite flat panels for things like root ribs, wing dihedral braces, servo mounts, battery trays etc. these are very light weight and have great strength.

speedracerntrixie

My Feedback: (29)

Flat panel details. The glass panel is 12"x12" and weighs 50 grams, thickness is 1/8".

Pylonracr

Pretty cool Shawn. What did you make that wing socket out of? Looks like epoxy and glass cloth, but it seems kind of transparent. 1.5 ounce?

Scott

speedracerntrixie

My Feedback: (29)

Scott, it is 3 layers of 1.4 oz. No real strength needed. These will go into the wing and the last tube which goes into the fuse will be a bit stronger. Making tubes is actually a bit more involved then what I originally thought.

Pylonracr

I found that making tubes is pretty easy, making tubes that you can get off the mandrel is another story. I have sent many carbon fiber tubes to the trash with the mandrel still attached.

Scott

speedracerntrixie

My Feedback: (29)

Exactly the issue I was having. Not so bad making them on aluminum tube as the mandrel but this go around they were made on a CF wing tube. First try was putting 2 layers of packing tape on the mandrel and waxing. I had to split the tube to get it off. Next I wrapped the mandrel with 2 mil plastic painters tarp material, did the lay up and then spiral wrapped the works with more 2 mil plastic. It was rather easy to get the sleeves off the mandrel this time but I'm not completely happy with the exterior finish. Next run through I will spiral wrap with peel ply and then bag.

I did cut the sleeves to length and then cut some root ribs and ribs and sleeve supports out of some fiberglass skinned Diviycell.

kenh3497

"Someplace" I read "somebody" used two wraps of wax paper on the mandrel then glassed over it.. The mandrel had a thin line of vaseline to hold one end of the paper. Then the paper was given another thin line of vaseline to hold the paper from unraveling. No vaseline was exposed to the epoxy/glass. I'll see if I can find a link.

Ken

speedracerntrixie

My Feedback: (29)

Ken, I did see a You Tube video of someone doing just that. I'm sure there are several ways that will work, I just need to find what I like best. That being said, today's project was to get the sleeves and end plates into the top wing panels. Everything is jiged up in the shucks and drying as I am typing this. Won't be too much longer and I will have 4 sheeted wing panels.

kenh3497

Looking good!!!!!!

speedracerntrixie

My Feedback: (29)

Yesterday I sheeted the second bottom wing panel and today they have been joined. The joiner is a peice of 1/8" vertical grained balsa with 3.7 oz glass on each side. As you can see it ties into the wing skins. Depending on weight, I would like to glass and paint all the wood surfaces. Usually on something like this I will glass with 3/4 oz cloth with an 8" overlap in the center and then an additional 10" layer of 1.4 oz in the middle. If I end up having to use iron on film then it will be 2 layers of 1.4 oz cloth 8" and 10". I think I have it straight enough while the epoxy cures.

kenh3497

It is definitely off by 1/64". Well maybe it's off...... LOL

Looks good to me. I'm a bit surprised at the one piece wing but it is a way to make it more rigid and makes mounting a bit simpler. Maybe a one piece is the norm for F3A bipes?????

Ken

speedracerntrixie

My Feedback: (29)

I did a few hours of internet searches before I started this project and saw that most F3A biplanes had one peice wings for both top and bottom. I like this for the bottom as it provides good access to equipment with the wing off and the flange that is created in the mold will help keep the mold true. It also will provide access when seaming the fuselage. I saw some pylon mounted wings which I didn't like as I feel it is a missed opportunity to gain some rigidly. I knew I would need a battery/motor access hatch up front but did not want to make a second hatch for the canopy/wing cover. A plug in top wing made the most sense to me. It adds a great deal of strength which has allowed me to build the lower wing a bit lighter because of the box arrangement the whole thing makes.

now onto the next hurtle, wing adjusters. Because the wing is quite thin there is not much room for wing adjusters and they are actually a bit heavy. I'm considering not having them on the upper wing. The plan right now is to start with the top wing at zero along with the motor and stab. The bottom wing will start out at + .7 degrees. If I need to adjust the top wing, it would not be too difficult but would not be a field adjustment.

Pylonracr

Should be flat Shawn, that sheet of marble helps. I use a sheet of thick glass on my table saw table, which right now has a piece of carbon - Divinicil - carbon vacuum bagged to it. I like the idea of iron on film for the wings and tail for weight reasons. That being said, you have seen the junk I fly, it is light but not likely to win any beauty contests. On your plane, paint will probably be another half pound when it is all said and done?? Significant, even if it is not as pretty.

You going to put a real engine on this thing, or is it still going to be one of those battery powered things like we had when we were like 7 or so???????????????

Scott

speedracerntrixie

My Feedback: (29)

Well Scott, you know how much I dislike Monokote. It's just that it is practically impossible to have it look show quality up close. We will see what the weight is when it is all together. The nice thing about going electric is that it does not need fuel proof paints so the actual colors are a bit lighter. It all comes down to how the parts are glassed. I'm going to run some tests on adhering the cloth to the wood with some Klass Kote clear as opposed to epoxy. I think that would save some weight.

The only thing that I don't like about electric power is the 8 minute flight times. The motor setup that I got for this ( NIB swap meet find ) will swing a 20x12 at close to 7,000 rpm. That rivals a YS 185 that does a 20.5x10.5 at 8,500. Other advantages is less vibration, no fuel soak and airplane weight stays the same ( 20 oz of glow fuel is heavy ) so flight characteristics stay the same. Not trying to sell anyone on electric power, just letting you know where I stand.

I am also back on the Miss Norway. I need to get that finished up as well. As long as I am cutting foam and bagging wings there is no excuse not to get those parts into the mix.

Pylonracr

Shawn, I know how much you like Monokote and you know how much I like weight. I just resigned myself to the fact that I never will have the nicest looking plane. They look fine flying by though. There is quite a lot of area there with both wings and the tail. I guess the test would be with a piece of balsa (say .5 square feet) weigh it, then glass, prime, and paint. The difference should give you a reference when you figure the area of the aircraft.
I was going to ask you the weight difference between glow and electric. Glow engines are heavy, as is fuel. Batteries get heavy as well. I never compared since I don't have anything electric. The airframe can be slightly lighter with electric power since the engine is not trying to shake it to death, so I guess that needs to be taken into account as well.
It is looking good. Did you plan far enough ahead; will this thing fit in your car?????

Scott

speedracerntrixie

My Feedback: (29)

Yes, the fuse with spinner is 78" and the wings are 75". I will need to order up a double 80" wing bag. The way this is being built, I don't think the way this is being built it would handle the vibes of a YS 185-200 for very long. Things would have to be a bit stronger.as of right now the rules require that the airplanes weigh no more then 11 lbs. electrics are weighed with batteries, glow models are weighed without fuel so the reality is the glow airplanes at take off weight can be a pound heavier. I just did a quick sanding job on the bottom wing and put it on the scale. Pleased to see it at 310 grams or just a bit over 10 oz. I think the bottom wing RTF at 1 lb is possible. The top wing may be a tad heavier so I estimate both wings with struts at 2.5 lbs.

Pylonracr

What, you are going to order a wing bag??? Have Trixie make one for you. I will loan her one of my sewing machines if she needs one. Get quilt material (Cheap sleeping bag material) from the fabric store.
Scott

speedracerntrixie

My Feedback: (29)

She says buying them would be way cheaper then the amount of wine I will have to provide for her to make them LOL. I think you can relate.

Got the first upper wing into the bag this morning and will get the second in the bag tomorrow morning. I started working on the stab cores and was able to get the hole cut for the stab tube. So far all the root ribs and tube supports for the upper wings and stabs have been made out of Divinicell with two layers of 1.4 oz cloth bagged on each side. This material is about the same weight as 8 lb balsa but just as strong as lite ply. I am experimenting with some Divinicell with CF bagged on that I want to use as the firewall and gear mount. In order to do this I will have to sleeve the mounting holes with CF tube to keep from crushing the material when screws are tightened. If that doesn't work out I will do some using a couple layers of 1/32 ply along with 3 layers of 5.7 CF. I have used that ply layup a couple times now with great results but always looking for a lighter option.

After talking to a couple well known pattern pilots I have decided to go with a normal plug in stab with elevators and adjusters. I will post some pictures of the stab root ribs with the adjusters installed when they are finished.