3-D Flyer

My Feedback: (150)

Hey guys.... anyone building this thing? LOL, man this thread is quiet lately, o well, Just thought i would chime in and let you guys know about my progress. I have done a nice mod with the fuel tank to get it on the CG. It is located under the wing tube.... I swithched it out to a 16oz Dubro tank. My D/A-50 came yesterday so i had a chance to weigh everything RTF. final tally this far is 14# 7.3oz Dry with the D/A and stock muffler. The weight also includes a mod i did on top of the gear to help re-enforce this area. 1/4" ply and tri-stock. I also moded it to have cowl mounting blocks insted of the ring. (just my personal preference) I have not yet cut the cowl or drilled out the spinner backplate or prop yet, so that will save a tiny bit. If i choose i can shed another 2.5oz with a C/F spinner as well. I am really trying to get this thing down to 14# Dry RTF. On the giants forum there is a guy who had his come in at 15#7oz dry with a BME44 so i am pretty pleased where i am at thus far. If anyone would like to see the Tank/cowl blocks/ Gear area re-enforcement pics let me know and i'll post 'em here..... Man it's been quiet around here!

Ohhh, the weight i came up with was done on a NEW digital postal scale, everything was weighed finished.... meaning hardware adhesives etc, are all in there....

The MacDaddy

My Feedback: (10)

pics please!

3-D Flyer

My Feedback: (150)

Just got the motor insatalled.... I'll get some up tonite.....

Flylow

Mr. Pettit-
Hope you've had a chance to work on the Yak. How about an update please?

3-D Flyer

My Feedback: (150)

These pics show the relocation of the fuel tank. I used a Dubro 16oz. Tank. I just cut out the area needed under the tube with a razor saw, then added a small balsa block under the gear plate to stop it from moving forward. The sides of the tank i "cusioned" with sticky back velcro so it pads it and holds it firm, then i just added square balsa spanners to hold it down and one in the rear to keep it from moving aft. This thing is not going anywhere!
The nice thing is now it is dead center on the CG so the cg will not change much at all during flight.

Next pic shows the stock tray i used in the far aft postion for more rearward weight for balance. Note the servo wire chase tube i used to neatly route all the wires to the rear. Takes a little finnesing to get it in there but it can be done. Then i just tacked it w/ epoxy to hold it in place.

Lastly you can see the way i beefed up the gear plate.... I used 1/4" lite ply and cut a cardboard template for a perfect fit before cutting the ply. I used longer gear screws to go all the way thru to the existing blindnuts below. Then i used tri-stock and epoxyed everything into place against the fuse sides. The gear is still revovable by doing it this way however increases the strength of the 2 piece gear which in my opinion is weak.

3-D Flyer

My Feedback: (150)

Next is a couple pix of the D/A-50 mounted. This was pretty much stright forward..... found a template here on RCU, can't remember the forum but they are out there just run a search. Line up the crosshairs on the template and firewall, and drill it out, simple and easy. I am using the D/A 3" standoffs and this puts the thrust washer just a hair over the recommended 6.75" mark. PERFECT! Ignition and NIMH pack is located on each side of the engine box.

Next you can see the Blocks i used to mount the cowl. I just did not like the ring. I have always mounted my cowls this way.....why stop now! I used the stock blindnuts to "fasten" the blocks in place along with sanding the surface for better bite for the epoxy. Later when i mount the cowl i will use small wood screws and rubber backed washers for the attachment.

The Stock D/A-muffler is going to be CLOSE!! Not sure yet if it's going to clear the cowl to my satisfaction yet.... still did not arrive yet, I used one of my D/A-100 mufflers for a guesstimate and it looks like it is going to be really close so we'll see. If it does not clear a pitts muffler will be the ticket.

3-D Flyer

My Feedback: (150)

Lastly for now is the Elev/Rudder servo links.... I threw out the stock stuff and used 4-40 allthread with CarbonFibre sleeves. Heavy Duty 4-40 Dubro ball links and Locking clevises. I did use the stock horns as i never had trouble with them before. I did the same setup on the aielerons as well.

Now it's off to the throttle servo and cutting the cowl.... gettin close!

lazy eight

My Feedback: (389)

Looking real nice what is the all up weight gonig to be with the DA 50 on it? I was looking at this kit at the local hobby store today and have a new DA50 thats laying around.The plane is a vary nice looking kit. I,m just a little worred about wing loading.

3-D Flyer

My Feedback: (150)

Thanks, see post #151.....

Flylow

3-D Flyer,
Where did you get the sleeves to go over the 4-40 all thread? Can you tell if the sleeved 4-40 all thread is stiffer than a solid 4-40 unsleeved?
Thanks

3-D Flyer

My Feedback: (150)

I got them from my local hobby shop, if i recall they were made by Midwest products..... as far as stiffness goes Yes they are definately stiffer because the CF does not alow the allthread to flex. If you were to run allthread alone without sleeving it there is a good chance it would snap. The nice thing about this setup is no soldering.... I will never use solder clevis's again. I had them on a quarter scale years ago and luckily on that plane i had duel rudder servos on a push pull. One of the solder clevis's broke loose and my son saw it just as i was about to taxi out! Then later after that happened i did a good check up on them and found another one loose on an elevator half! Needless to say i changed everything out to this type of setup. Gives you the ability to cut the rods to the exact length you need and have a clevis and ball link threaded on each end. No worries about it pulling out that way!

3-D Flyer

My Feedback: (150)

Throttle servo tray..... nice and close linkage. Using a Hitec mini 225mg. I ran out of metal clevis's so i'll have to pick one up to finish it, no big deal. All that's left is the cowl mounting, but i need the muffler before i start cutting... hopefully it will be here tomorrow or monday. I'll post pix of the opening when i get it. Hope the stock muffler fits, My gut feeling is it will not, but as i said earlier it's going to be close...
Then i drill out the prop and spinner and dress the wires, that's about it! This was a pretty quick build. Our field out here is getting a new entrance and parking lot so we are closed down for a little while[] Sux too, the wether is starting to improve, go figure

AirTech

My Feedback: (18)

Hey 3DFlyer

Very nice work on those mods. I am definitely going to try the tank under the wing tube for sure. Haven't had a chance to start working hard on mine yet since I have been helping some friends build their planes. Just finished putting together a EF Extra 300 for a buddy, a sweet litle electric plane. Probably this week end I will get hard on building my Yak. I am still waiting on the engine (an Evolution 45GX) that should arrive next week. Will post photos as I go along. Last weekend got a hold of a quarter scale Lifelike Pilot but from Cajun RC and just finished painting it.

In regards the CF pushrods over the 4-40 allthread, that's how I used to build them before I learned a neat trick from the guy at Aerospace Composite Products at last year Toledo Expo. In his seminar he showed us how to buy the CF rod about .125" smaller I.D. than the 4-40 rod. After measuring the desired length he cuts the CF rod minus 2". Then he slides a 3/4" piece of brass that fits the exact O.D. of the CF rod at both ends and epoxies them in place. Then he cuts 4-40 threads in both sides and slide 1 1/4" pieces of 4-40 rods which gets epoxy in place 1/4" inside the threaded CF rod. These are super light, strong, and very stiff pushrods. Good luck and keep us informed on your progress.

3-D Flyer

My Feedback: (150)

Thanks AT.... Yeah, i have seen other ways of doing pushrod installatons, I just prefer it this way as there is no adhesive worrys. Cut to length, screw on ball link, clevis and that's it. Very strong and quick. I never liked the solder connections.... a very week point especially if not done correctly! Looking forward to seeing your progress... I just wish there was more people building this thing.... But there are so many Yaks out there now, it's like take your pick. After assembleing the airframe as a whole yesterday, I see the biggest issue on this plane is going to be the gear. I just feel it is going to be really mushy, especially with the gas engines. That's why i did the plate mod off the bat. But that is not going to help the flimsyness of the gear itself.... so we'll see what happens. I feel if a replacement is offered by tnt it may be a good upgrade, to stiffen them up a little. Alltho there will be a weight penalty, which on this bird is going to be an penalty! I wonder if there will be a 2 piece CF gear available....

AirTech

My Feedback: (18)

33-D Flyer

Does it look the gear is too weak even for a DA 50? If that's so a CF replacement may be the way to go, and these may be available in the near future. The Evolution 45GX should weight 2.8Lb bare and I'll have to see how the gear stands up to that weight. The gears on GP planes are a week point on several of their latest offerings. I built a GP Super Chipmunk for a friend, and with a Saito 150 the gear was too weak to stand the any landing other than a perfect grease job, or the bent. The GP U-Can-Do's are great 3D planes, but the landing gear will shear off extremely easy. I suppose we will have to wait and see how the Yak gear perform
.

evfast

My Feedback: (31)

Is the cg right in the manual 5 1/8 from the leading edge? I have a DA 50 and 3 servos in the rear 2 batteries up front and the plane comes in tail heavy?

3-D Flyer

My Feedback: (150)

evfast, where is your ignition pack and ignition pack mounted? Are you using the stock spinner? I have not yet balanced mine yet, i am still waiting on my muffler so i can mount the cowl,spinner and prop then i'll see where i come in at. Where are you balancing at now? Says you can actually go 1/2" forward or back from the suggested 5- 1/8 point. Man, i thought i was going to be nose heavy! We'll see.....

evfast

My Feedback: (31)

3D

Ignition module is on top of box, battery for pack on the side, receiver pack is under the tank, receiver is in the middle of the fuse. If you use the regular stand offs that comes with your DA you will have to add at least 3/4 wood blocks for the model to balance with out adding lead![:'(]

I have just 3 servos on the back. You might want to consider the pull pull setup. She balances at 5 3/4 I will maiden her tommorow AM.


later

evfast

My Feedback: (31)

I forgot! My spinner has not arrived yet. The battery packs are as follows ignition 1650nmh receiver 2700nmh, 2 smart-fly switches.

seanychen

My Feedback: (4)

evfast:

I thought the plane came with a spinner.

evfast

My Feedback: (31)

Plane does come with spinner. I have a 23X8 Mez, spinner does not fit over that.

Hajduk

Well, I am waiting for BME 55cc so I am not in a hurry with my Yak. Thanks for letting us know about that fuel tank mod.

evfast

My Feedback: (31)

Well today was the maiden flight. All I can say is that it flies great the DA 50 has more then enough to push her around. Landings are very stable 2 cliks of throtle and let her touch down. I will be moving the rudder servo to the center of the fuse for CG purposes.

The gear holds up very well with a 23X8 prop, will see after some time.

3-D Flyer

My Feedback: (150)

Evfast... Glad to see you got her up! So, where did you wind up balancing at? apparently it is ok because you flew it...... why not just dremel the spinner to accept your menz prop?
Did you do any 3-D manuvers yet? This is where i really waiting to hear reports..... hovers/tourque rolls, harriers etc....
As far as the standoffs go, you must be using the older set.... now D/A gives you the choice of the short ones or the newer 3" ones. The 3" ones will put you right at 6.75" without using any blocks.... just a heads up.
Glad to see you got her up! Keep us posted! What was your final flying all up weight dry? And what size tank are you running?

Hajduk

Congratulations Evfast! I can’t wait (2 more months) to see my Yak in the air.