Getting into Gassers

Started by chanvivek, March 31, 2009, 11:20:46 AM

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Pikle6

oops sorry i am a bit too illiterate in gas and glow and anything like that i just saw that the name was somewhat similar so i posted it sorry
E.V.Subramanian
Yak55|EasyFly Glider 1.9m|Skyfun|Easystar II|Quad Talon V2|Mini Saturn

chanvivek


rckatty

@ chan & gaurav,

can we have some pics of your models. Like the box, a peek into the arf. Also it will give us a idea as to how big the box is
Hangar: SU27 .90, Escape .46,
RDS8000 2.4ghz,
GS Racing 1/8 Truggy,
KM 1/5 Baja,
MX-3 FHSS,
coming soon *XRAY XB808*

gauravag

Chan,
Any idea how much Amps would the Hitech 7955 pull ?
Futaba officially claims that their RX bus can handle current of 5A with peaks of 8A .
http://www.rcuniverse.com/forum/m_8754173/tm.htm

with the 5 7955s, i guess our load rating is going to exceed this ? Note that higher current will cause the bus to heat, and then their are potential heat issues with the Futaba FASST Rxs ..

Let me know what you think.
-Gaurav

anwar

No issues with 5x7955s and Futaba receivers (2.4 or 72).  The thread below has the Hitec rep confirming the same.

http://www.flyinggiants.com/forums/fg29/22093-new-hitec-7955s-24.html

Hangar : Please see my introduction.
RC India forum and me : About this forum.

chanvivek

Thanks for that Anwar.. Gaurav's post had me worried for a moment!! But people use more servos with the same Rx on much bigger planes and jets!

Attaching some pics of my model.. Please excuse the quality as it was taken indoors with my mobile cam..

Would be posting some more pics as I proceed with the build..

- Chan

chanvivek

Some more pics..

gauravag

Chan,
Your plane looks great. I also think that the 7955 "should" be fine with the Futaba Rx, though people using more servos use powerboxes that help distribute power to the servos, and so that they do not just rely on the RX as their power source.
BTW, i ordered the A123 pack from Hobbicity, so should have then pretty soon.
-Gaurav

anwar

Chan -  Good use of a real life "model" to help everyone understand the true dimensions of the plane ;D   Hope he grows up to be another John Abraham (the good bits !)

Quote from: gauravag on July 20, 2009, 01:42:27 PM
Your plane looks great. I also think that the 7955 "should" be fine with the Futaba Rx, though people using more servos use powerboxes that help distribute power to the servos, and so that they do not just rely on the RX as their power source.
-Gaurav

The "power boxes" add another level of "peace of mind", but at the 5 servo level, the criticality is fairly insignificant, it seems.
Hangar : Please see my introduction.
RC India forum and me : About this forum.

chanvivek

Hi Everyone,

The hinging of the wings is complete.  The kit came with Robart style hinges.  Since this was the first time I was using these hinges, I took help from a more experienced flyer for getting these sorted out.  We first started by dry fitting the ailerons to the wing and marked the spots where the gap was uneven.  The holes into which the hinges seat were then filed accordingly and dry fitted again till the fit was perfect.  Once we got the fit right, we applied vaseline on the swivel part of the hinges to avoid accidental epoxy hardening on the pivot.  Then we mixed some 30 min epoxy and applied it to the hinge holes in the wing and also the hinges and aligned them on the wing.  Care should be taken that the pivot is perfectly perpendicular to the wing to achieve the hinging action.  Some more pictures would have helped, but I just happened to have a few taken after the hinging to observe the aileron fit.

Once the epoxy hardens on the wing side, then apply epoxy on the aileron portion and the other side the hinges and slide it in till the fit is achieved.  Once that is done, move the ailerons on either side once till max deflection is achieved.  Then center aileron and let the epoxy cure.

- Chan

rcforall

Any one selling a used gasser  air frame I am interested .

Sai
www.zuppa.io : vehicle telematics, ADAS, IoT , Drones

Pikle6

hey chan bhaiya just saw you were online any update on the 50cc yak build



subbu
E.V.Subramanian
Yak55|EasyFly Glider 1.9m|Skyfun|Easystar II|Quad Talon V2|Mini Saturn

chanvivek

hey subbu,

still no improvement.. having work to do on some other planes.. so 50cc on hold temporarily!! Converted my Yak 50 from electric to glow!!

- Chan

chanvivek

Hi Guys,

Work resumed on my gasser.. Looking for an early next week maiden.. As seen previously, I had completed hinging of my ailerons.. Let me go into aileron servo mounting next...

This was a little difficult to get across..

I first used some thin CA and hardened the servo mounting plate on the wing.. Then I put an extension through the wing and connected the servo and mounted the servo.. It was a perfect fit without me having to do any sanding!! The servo hole was perfectly aligned and set for the Hitec 7955 servo.. Next I had to do the control horn mounting.. All the pushrods were ball link joints and I was very much new to them..I mounted one end of the ball link pushrod to the servo arm using an allen bolt and a checknut.. I marked the other end on the aileron and setup one control horn and aligned it at 90 degrees to the servo arm.. After marking it and cutting open the monokote, I hardened the part using thin CA again and fixed the control horn using 4 wood screws.. Now I had a problem.. When the push rod is 90 deg from the servo arm, I do not have enough plywood in the aileron to mount 2 control horns.. So I left it with only one arm.. And after hunting a bit on the internet, I found that they suggest mounting the pushrod at a slight acute angle to the servo arm.. So I guess I have to do a little bit of rework on it now!  I did the same thing to the other aileron also..

Let me continue with the elevator hinging and servo mounting in my next post.. Would also put in some pics later on during the day!!

- Chan

chanvivek

When I updated the thread this morning, I did not have to make any cosmetic changes but as I am writing this, I have to compromise a bit on my rudder hinging..

The rudder robart hinges did not seat properly and it took up most of today to rip off the epoxyied hinges and I used a slot machine to cut regular slots in the rudder post in the fuse and the rudder.. I have used Klett nylon flat hinges used in 1/4th scale applications instead of robart hinges on the rudder alone.. Had to compromise a bit on the looks of the tail post, though it wont show much once the rudder is mounted.. but it was a bit messy!!

Engine mounting and rudder servo mounting is scheduled for tomorrow morning.. Am going to hinge the rudder now on the new hinges and also stick the canopy!!

- Chan

chanvivek

Build Update..

Elevators were hinged similar to the ailerons.. There was absolutely no flaws on that one.. It sat very easily.. Little bit of filing had to be done for them to get that perfect seating!!

The elevator servos came inside the elevator halves with just the arm jutting out of the elevator half.. This again has dual control horns and ball links.. As usual I had hardened the wood prior to servo and control horn mounting using a good deal of CA!

After hinging the elevator halves and mounting the servos, I connected the wings and the elevators one by one to a Hitec servo programmer and programmed them with the center points and end points! And checked whether they worked in sync with each other..

After a paranoic inspection of the wings and elevators, I kept them aside terming them ready to mount !!

Then I stuck the Canopy onto the hatch with canopy glue.. But now it looks like I have to do some minor surgeries to make it seat properly in the front.. Nothing major or cosmetically damaging though!!

The stock landing gear was mounted along with the stock wheels though I might upgrade to Dubro after the maiden flight.. Tail gear was pretty bad and took quite a while to settle and that too I had to dump a load of epoxy to make sure that the tail wheel swings in sync with the rudder!

Engine mounting was completed and cowl cutting is done to a pretty much decent level today morning.. Was very straight forward and it sat flush using 2.5" stand offs!

Now just woke up from my siesta and sitting on the work bench.. Agenda for tonight..

1. Rudder servo mounting
2. Throttle servo mounting
3. Canopy rework
4. Engine finalized mounting
5. All plumbing..

Looking forward to taking the plane to the field tomorrow morning and having a field test.. Should work out ok if I am on schedule tonight..

Cheers !!

Would have some pics definitely tonight.. Thanks guys..

- Chan

Pikle6

please please please give us some pics after you are done  (:|~ (:|~ (:|~ (:|~


subbu
E.V.Subramanian
Yak55|EasyFly Glider 1.9m|Skyfun|Easystar II|Quad Talon V2|Mini Saturn

chanvivek

Hey guys,

Maidened and flew the plane today evening! Would post a detailed report tonight.. time for some pics from the field today evening..

- Chan

chanvivek

some more pics

chanvivek

some more pics..

atul_pg

Wow superb chan  {:)} {:)}

Congrats on the build man...

Bad luck with the rain god..

cheers  {:)}

atul g.

Pikle6

great chan bhaiya  waiting for the report and the video toooooooooooooooooooooooooooo (:|~ (:|~ (:|~ (:|~


subbu
E.V.Subramanian
Yak55|EasyFly Glider 1.9m|Skyfun|Easystar II|Quad Talon V2|Mini Saturn

rcforall

www.zuppa.io : vehicle telematics, ADAS, IoT , Drones

chanvivek

Hi guys,

High time I updated this thread...

Let me continue with the build thread..

The rudder servo mounting was one of the easier parts of the build..  The servo sat easily on the tray and the pull pull rigging was also perfectly done... Two control horns were installed on either side of the rudder.. The supplied stock pull pull cable is very strong and is definitely not going to snap!

Throttle servo was placed right next to the tank and took a straight linkage to the throttle arm in the engine.  No bends on the pushrod.. The engine side of the pushrod was linked using a Great Planes Ball Joint and on the servo side, I used a small aluminium arm with a pushrod retainer.. Worked perfectly fine..

Canopy rework was very minor and required a little bit of stickering..

The plumbing and engine mounting were also very straight with absolutely no problems.. Pictures would speak for themselves!

My next post would be about testing the plane and programming it!

- Chan

gauravag

Sounds cool !
Awaiting pictures and engine test report.
Now i just got my engine + servos, and noticed that the props require drilling. Have you done yours ? Seems that this needs some precision work here.
-Gaurav