MP3_tilaco

Thanks Eduardo, your idea is perfect for this problem, this way is very easy and work fine. Eduardo share a lot of good idea for the Hawk, I hope you will fly your plane before the mine...

MP3_tilaco

I have a question, I'm working in the turbine instalation and I wonder if the fuel pump affect the ICS ?, I don't install the receptor near the fuel pump but what happend whit the ICS?

jclittle

My Feedback: (99)

Is anyone having to add any weight to get these Hawks to balance? In the nose or tail? I'm just wondering as I build mine out to make sure I'm placing things in closer to the front or back.

Ch!eF

i wouldnt use nylon horns on powerfull servos like jr8711 or hitech5955tg the splines cant stand the force i have seen it so many times on the comp-arf aerobatic planes you can force the surface by hand and feel the splines pop, with power on the servo with no input so you can actually position the aileron or rudder or elevator in any position you like , thats why i allways use aluminum horns .

mat

Hope this is not seen as hijacking this thread. I have an old skymaster hawk that im just finishing put together i was wondering if anybody knows the correct position of wing fences and at what angle they should be mounted ie in refrence to centre line of fuselage.

Jim Cattanach

Don't know the exact position on the SM hawk wing, but the fences should be exactly aligned with the fuselage.

jclittle

My Feedback: (99)

Still looking for some feedback on the balance before I lay everything out. Thanks!

johnls

I have just bought the previous version of the Skymaster Hawk. It only has one elevator servo whereas the later version appears to have two. Is this correct and safe?
John

MP3_tilaco

Hi, I'm installing the elevators servos and I bought a JR arm, the problem is the link for it, JR's arm has a 4-40 hole for the link.
I see Dubro HEAVY DUTY 4-40 BALL LINK, what do you think about?, is correct for the elevators?

jclittle

My Feedback: (99)

Just a heads up to anyone thinking about building this plane...if you plan on using the SM cockpit, you can't use the front tray to mount radio gear etc... On the rear tray, be prepared to mount everything as low profile as possible. It would be really great if Skymaster USA or Anton would share these things in advance, although since they provide really poor directions and just about everything on the plane needs modification I can understand. Just what is Skymaster USA here for anyway? [:@]

tp777fo

My Feedback: (28)

To take your $$$$$$$$ I just got the cockpit kit too and just scratched my head and laughed. Instead of calling them an ARF they should be called a "prepainted kit"

steveline9

Hi Guys, im just building my SM HAWK and have also come across the build issues in previous postings. I noticed that on the instructions it recomends 30mm flap for takeoff as well as landing. Surely this cant be right as the MK1 model only used 7mm flap for takeoff. Surely this model would leap off the floor with 30mm flap deflection on takeoff. Anyone flown this model yet with takeoff flap?

Cheers

jclittle

My Feedback: (99)

I've completed the build out of the inside of the Hawk, now I just have the doors to finish and then it will be ready for the maiden.

Several people were stressing over the SM recommended location of the tanks, for good reason as they would easily cause a flame out if installed as SM recommended. Thankfully Eric Clapp put me in touch with Rob from RC Hobbies that was also building out a Hawk for a customer and he recommended the set up shown in these photos. First close up the SM pre-drilled holes using BVM poly-ply and Hysol. Then using BVM fuel pick ups and vents you re-plumb the tanks to fit as the photos show. This places the tanks over the CG still, but they can lie down horizontally rather then stand vertical as SM recommends. I built shelves for both the lower and upper tanks. They fit perfectly this way and initial tests show they work perfect (thanks Rob!).

The other challenge was to keep all the components out of the way of the cockpit kit; you can’t use the provided front tray at all, so some serious modifications are needed. All the components on the rear tray need to be tucked off on the sides or directly in the front part of the tray to avoid any contact with the cockpit. Note the location of the air tanks as well; this is the only place they will fit other then right next to the turbine.

Although I have not done a final balance yet, it seems to be slightly tail heavy, maybe 1 pound or so of lead will be needed in the nose. If anyone that has flights on this can tell me about the correct CG that would be a big help. For now I’m going to go with what SM says in the manual.

Last, I understand from Rob that the gear doors also need some serious modifications from the SM directions, he has provided some good directions and I will post the results in a few days.

tp777fo

My Feedback: (28)

Nice solutions to nagging problems. I had planned on 2 Dubro 50oz tanks but I like what you did. Did you just mount stuff on the floor of the fwd fuse? I have my elev re-engineered but still need to start gluing in the new tray supports. I used Sierra Precision aluminum servo mounts...very nice. Use the green futaba to fit the JR 8711. I had to cut a goove in the hold down for the tray which will be a little weak now. I plan to put a 1/2" triangle stock under the tray support for reinforcement. 3/8" maple blocks will be used to lift the new servo tray high enough to the the linkage to line up correctly they will now serve as the attachment points for the new servo tray. Basically I did what the guys in Chile did. I hope to mount the cockpit kit on the canopy so I can access the stuff with the canopy removed. The fwd gear doors were reinforced with cf and cut to be scale like. It works well. The mains were easy also as I used the threaded hole and groove in the trunion to mount a 1/16 wire with a balsa block on the door to pull the door shut. The wire slides on a small diameter brass tube as the gear extends or retracts. A dubro hinge holds it at the pivot just outboard of the trunion. I ca'ed a polyply tab on the strut door for the main doors to push against to keep the strut door from flapping in the breeze. I'll try to get some pix when I can but I'm on the road until late next week.

MP3_tilaco

Hi Tom, I did it in my elevators servos

I didn't used the aluminium servo tray because is not usefull, I used Midwest plywood whit a lot of epoxic and CA + activator.
I thought which are the best link, I used JR arm and Dubro HD Ball Link.
I'm installing the turbine and servos wire but I have to buy the FOD Screen I hope I'll get it in 2 weeks.



I'd like to see your work with Dubro's tanks, in Chile some SM tanks had some problems because give off a little of fibres, I think Dubro tanks is safest than the SM tanks.

JCLittle, nice job.

MP3_tilaco

[:-]

tp777fo

My Feedback: (28)

Nice work MP3! I will try to get some pictures soon.

jclittle

My Feedback: (99)

Tom, I cut a piece of 1/8" midwest ply big enough to hold the Rx, matchbox and regulator. It's held to the floor with velcro and can easily be pulled up if necessary. I opted not to mount the cockpit to the canopy, I could have easily, but I did it on my FB MB339 and its hard to get inside and clean it. So this time I wanted it to be seperate.

I would like to see some photos of how you did your gear doors before I start mine, but want to get to it this week while I am not traveling. It sounds similar to what I'm going to do. I'm going to use the same spring method that BVM uses on the Bandit ARF.

jclittle

My Feedback: (99)

MP3 - what did you wrap your rear (ELEV & RUD) servo wires in? I put a BVM blanket over the ELEV servos in the rear section and it also covers the wires about half way back to the turbine inlet, but they are exposed from that point forward. It's about 3 inches from the pipe, but want to make sure no heat damage to the wires.

MP3_tilaco

I bought in electronic store a cover in fiber and silicon, in the pic the cover is not the latest (is black), the new one is white. This cover protect until 200 ºC.

jclittle

My Feedback: (99)

Is anyone having an issue with the struts not being tight enough? How are you overcoming this? When the plane is one the ground sitting it bottoms out the struts.

tp777fo

My Feedback: (28)

JCLITTLE.....I wishl you would stop buillding your jet...everytime you do something you find another problem to solve. A box of sticks kit would be easier to build. I hope to get some work done on mine over the weekend.

jclittle

My Feedback: (99)

Tom - Mines pretty much done, so hopefully this is the last of the issues . Going to try for the maiden tomorrow if I can get some air in these tires and get the struts a bit stiffer. Keep at it man, it gets better!

tp777fo

My Feedback: (28)

Where is the neutral stab point on your jet? Good luck with the test flight!

john agnew

jclittle

It is very dissapointing to hear that the "new" version of the SM Hawk still has the problem of the oleos bottoming out. I had one of the original Hawks and this problem was highlighted many times on various hawk threads. The non-fitting cockpit kit is another issue which is unsatisfactory. At the World Jet Masters in 2007 Anton borrowed my home made scale cockpit to take back to Thailand to use as a prototype for the SM Hawk cockpit kit. He sent me a SM cockpit some time later and guess what? It didn't fit without some serious hacking about.

I am getting fed up with manufacturers who do not develop their models fully before releasing them to an unsuspecting public! Let's face it they are not particulary cheap. I don't want to have to stick bits of rubber in my oleos to make them work when I have paid several hundred $ for them. Instead of pumping out more new models how about some reverse engineering on the current ones?

John