Notices
WildHare R/C Support Disscuss WildHare RC products in this forum. Please note, answers may be provided by Tom Fawcett (owner of WildHare RC) or by the general membership.

35% Sukhoi - DA85 Build

Old 03-06-2008, 11:23 AM
  #1  
JAX FLYING REBEL
Member
Thread Starter
 
Join Date: Jan 2008
Location: JACKSONVILLE, FL
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Default 35% Sukhoi - DA85 Build

I'll be using the stock Pitts style muffler instead of the cans. so the only question I'll probably have in that area is how to plug up the opening to the can tunnel (lol). This is my second large scale buld so I'm not a complete retard just a partial one. So far the build is going well. Tom at WH has been great to work with and has been very helpful. Because of that, my future purchases will be at Wild Hare - period!

I'll get soe pics posted as soon as I can land this desk that I've been flying at work and home for the fun stuff - building my Suk.


ps: I realize that's probably not a good way to abreviate the Sukhoi name. LOL.

Old 03-06-2008, 11:24 AM
  #2  
JAX FLYING REBEL
Member
Thread Starter
 
Join Date: Jan 2008
Location: JACKSONVILLE, FL
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Default RE: 35% Sukhoi - DA85 Build

ps: I will also try to learn how to type while documenting this build.
Old 03-06-2008, 11:42 AM
  #3  
Tired Old Man
Senior Member
My Feedback: (1)
 
Join Date: Feb 2002
Location: Valley Springs, CA
Posts: 18,602
Likes: 0
Received 3 Likes on 3 Posts
Default RE: 35% Sukhoi - DA85 Build

The openng under the cowl will not have any negative effects if left open but if you still feel the need to close it off either a piece of 1/64 ply or Ultracote will effectively do the job. There really is not much of a wind load going through there. Keep whatever you decide to use light. Yu don't need any additional nose weight.
Old 03-06-2008, 12:08 PM
  #4  
rctom
Senior Member
 
rctom's Avatar
 
Join Date: May 2002
Location: Flower Mound (near Dallas), TX
Posts: 6,189
Likes: 0
Received 1 Like on 1 Post
Default RE: 35% Sukhoi - DA85 Build


ORIGINAL: JAX FLYING REBEL

I'll be using the stock Pitts style muffler instead of the cans.
I need to clue everyone in (again) about round fuse airplanes and mufflers.

With an Extra or Edge or a real Pitts the engine is mounted high on the fuse and the muffler is meant to hang down underneath, this is the way the full scale planes are designed and our engines mimic them.

Round fuse planes use a radial engine with a round exhaust manifold. When we try to model them the pitts type muffler is in the wrong place and usually ends up being too low and requiring a hack job on the bottom of the cowl.

This is why canisters are popular on round cowl airplanes. Please keep us informed as to whether your Sukhoi will accept a pitts muffler without major surgery.

TF
Old 03-06-2008, 01:04 PM
  #5  
JAX FLYING REBEL
Member
Thread Starter
 
Join Date: Jan 2008
Location: JACKSONVILLE, FL
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Default RE: 35% Sukhoi - DA85 Build

I didn't know I was going to have to do any surgery at all except 2 holes for the exhaust. On my xtra I had to do a large half moon. After seeing your post I may end up ordering a can for the 85. If I go with the cannister will I have to insulate my RX/Batts/Tank from it?
Old 03-06-2008, 01:55 PM
  #6  
rctom
Senior Member
 
rctom's Avatar
 
Join Date: May 2002
Location: Flower Mound (near Dallas), TX
Posts: 6,189
Likes: 0
Received 1 Like on 1 Post
Default RE: 35% Sukhoi - DA85 Build

Only from the vibration, there won't be significant heat.

TF
Old 03-07-2008, 10:12 AM
  #7  
JAX FLYING REBEL
Member
Thread Starter
 
Join Date: Jan 2008
Location: JACKSONVILLE, FL
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Default RE: 35% Sukhoi - DA85 Build

Tom,

I discovered a few clues myself last night. The pitts muffler would require two holes in the bottom for the pipes. The holes are so close to the existing cut that there would be a huge hole on the bottom of the cowl (not that that would be a problem) The real problem would be where the port side of the muffler contacts the inside of the cowl. Even though the cowl fits I wouldn't be comfortable with a vibrating corner of the muffler contantly rubbing against the cowl.
Old 03-07-2008, 10:15 AM
  #8  
JAX FLYING REBEL
Member
Thread Starter
 
Join Date: Jan 2008
Location: JACKSONVILLE, FL
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Default RE: 35% Sukhoi - DA85 Build

Ok here's some pics of the build:

I set the fuse on it's tail so I could center the motor on the firewal.

I also made sure the hinges didn't get damaged on the vertical fin by making a styo support. Once those break you are screwed.
Old 03-07-2008, 10:21 AM
  #9  
JAX FLYING REBEL
Member
Thread Starter
 
Join Date: Jan 2008
Location: JACKSONVILLE, FL
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Default RE: 35% Sukhoi - DA85 Build

I used standard procedures for mounting the 85. 3/16 left of center and one set of flat washers to angle back to center. I've read some stuff on here about flying without offset thrust and I dont buy it. Every plane is going to have P-factor unless yer flying a twin with counter rotating props (lol). Anyway here she is.


I also specked the inside of the fuse and the firewall. Not really necessary but it sure does look good.


Old 03-07-2008, 10:23 AM
  #10  
JAX FLYING REBEL
Member
Thread Starter
 
Join Date: Jan 2008
Location: JACKSONVILLE, FL
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Default RE: 35% Sukhoi - DA85 Build

I installed th RX switch and charging receptacles on the port side of the fuse. I'll put my DA there as well so excess fuel will spill on the ground instead of the wing.

Old 03-07-2008, 10:28 AM
  #11  
JAX FLYING REBEL
Member
Thread Starter
 
Join Date: Jan 2008
Location: JACKSONVILLE, FL
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Default RE: 35% Sukhoi - DA85 Build

If you are planning to install a DA 85 on this bird with a cannister then get enough drop on your header so the horizontal centerline of the header lines up with the second cylinder fin from the top of the cyl head.
Old 03-07-2008, 10:29 AM
  #12  
JAX FLYING REBEL
Member
Thread Starter
 
Join Date: Jan 2008
Location: JACKSONVILLE, FL
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Default RE: 35% Sukhoi - DA85 Build

Or put another way - The centerline of the cannister tunnel lines up excactly with the second cylinder fin.
Old 03-07-2008, 10:32 AM
  #13  
JAX FLYING REBEL
Member
Thread Starter
 
Join Date: Jan 2008
Location: JACKSONVILLE, FL
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Default RE: 35% Sukhoi - DA85 Build

Being a novice builder, I'm sure I will get several different opinions on how I should have done this or that differently. Just remember, there is more than one way to skin a cat. Thats what makes it so much fun anyway.
Old 03-07-2008, 10:45 AM
  #14  
JAX FLYING REBEL
Member
Thread Starter
 
Join Date: Jan 2008
Location: JACKSONVILLE, FL
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Default RE: 35% Sukhoi - DA85 Build

I have no idea where this bird is going to balance since I'm using the 85. I would love to hear from any one else that did a similar build on what they had to do to get her slightly nose heavy at the CG. I'm going to mount everything except the batteries and the rudder servo then mount those to get her right.
Old 03-07-2008, 11:00 AM
  #15  
Tired Old Man
Senior Member
My Feedback: (1)
 
Join Date: Feb 2002
Location: Valley Springs, CA
Posts: 18,602
Likes: 0
Received 3 Likes on 3 Posts
Default RE: 35% Sukhoi - DA85 Build

A BME 115 weighs less than the 85 and balance is no problem at all with a 115. It's just a matter of moving the batteries around.
Old 03-07-2008, 01:29 PM
  #16  
JAX FLYING REBEL
Member
Thread Starter
 
Join Date: Jan 2008
Location: JACKSONVILLE, FL
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Default RE: 35% Sukhoi - DA85 Build

Thanks PatRoy.

What kind of handling differences can I expect going from My Aplha 60 to this bird. For what its worth, I've been doing pretty good flying the Edge 540 35% on the FS One simulator. I'm going to buddy box with a fellow Hild Hare owner - cant wait to solo this bird.
Old 03-07-2008, 03:04 PM
  #17  
Tired Old Man
Senior Member
My Feedback: (1)
 
Join Date: Feb 2002
Location: Valley Springs, CA
Posts: 18,602
Likes: 0
Received 3 Likes on 3 Posts
Default RE: 35% Sukhoi - DA85 Build

It's a very neutral plane and goes exactly where you point it. The speed range is limited by that big open bucket up front so it's not super fast. Extended down lines do not pick up a lot of speed without adding throttle for the same reason. It flies very slow but the stall at very slow speeds is sudden (because of the big open bucket) and the nose drops pretty much straight ahead when it stops flying. Just don't try to bring it to a dead stop in level flight 10 feet above the runway. Stalls are easy to recover from and it generally does not drop a wing unless you are holding a control input that would effect it. The rudder at max deflections will generate a snap or stop the plane in a heart beat, which is why huge deflections are not needed at the rudder. It's very, very effective. The plane responds quite precisely to all control functions at any rate.

BTW, it flies just great for 3d flyers at zero-zero thrust lines. Some unlimited class IMAC people liked about 1/2 degree of down thrust for a precision sequence. It's a very easy plane to fly. As for how it compares to an Alpha 60...what's an Alpha 60?
Old 03-07-2008, 03:25 PM
  #18  
Grotesquebass
Senior Member
My Feedback: (16)
 
Grotesquebass's Avatar
 
Join Date: Sep 2004
Location: Suffolk, VA
Posts: 653
Likes: 0
Received 0 Likes on 0 Posts
Default RE: 35% Sukhoi - DA85 Build

An alpha 60 is a trainer this is the guy who was getting alot of s**t for jumping from a trainer to a 35% plane over on FG or DOD cant remember. Good to see your seeking help that helps avoid the possibility of a crash these planes fly great but do take some getting used to i just finished my new 35% extra and couldnt have asked for a better plane it flys just like the 41% Jax if u have any questions gimme a holler i will help as best i can i will quote the same things i heard when i painted my firewall all that paint on there adds useless weight gassers are not like glow and dont slime everything your gonna wanna keep the weight down using an 85 little stuff adds up in the end.. Did you paint the whole interior front to back?
Old 03-07-2008, 08:49 PM
  #19  
Tired Old Man
Senior Member
My Feedback: (1)
 
Join Date: Feb 2002
Location: Valley Springs, CA
Posts: 18,602
Likes: 0
Received 3 Likes on 3 Posts
Default RE: 35% Sukhoi - DA85 Build

Okay, I was afraid of that but I'm not going there. Just get experienced giant 3d scale or IMAC help when you fly it for the first few times. There's nothing wrong with a buddy cord and an excellent instructor that knows the type and size of plane you'll be flying. Some might try to BS their way through and try it on their own but having $3,000.00 plus wrapped up in a plane has a tendency to get most to see reality. There's no reason for a one flight wonder aside from arrogance and/or stupidity. Hopefully you don't have a corner on either. Aside from all that, enjoy, because you will most assuredly enjoy flying it.

It flies nothing at all like an Alpha 60. It will not ever self stabilize like a trainer will do, and it presents much differently than a small plane once airborne. Don't add any weight to a plane that is not required to install the components. Wild Hare aircraft require no additional bracing or wood to make them stronger or better. They are pretty near perfect as they arrive out of the box.
Old 03-08-2008, 04:30 AM
  #20  
RustyTumbles
Senior Member
 
RustyTumbles's Avatar
 
Join Date: Sep 2003
Location: Newcastle, AUSTRALIA
Posts: 802
Likes: 0
Received 0 Likes on 0 Posts
Default RE: 35% Sukhoi - DA85 Build


ORIGINAL: JAX FLYING REBEL

I installed th RX switch and charging receptacles on the port side of the fuse. I'll put my DA there as well so excess fuel will spill on the ground instead of the wing.


Are you sure the cowl will not overlap those switches. The cowl has a large overlap compared to other model.

I will be maidening my Sukhoi tomorrow with DA85.
Old 03-08-2008, 08:26 AM
  #21  
Grotesquebass
Senior Member
My Feedback: (16)
 
Grotesquebass's Avatar
 
Join Date: Sep 2004
Location: Suffolk, VA
Posts: 653
Likes: 0
Received 0 Likes on 0 Posts
Default RE: 35% Sukhoi - DA85 Build

sure hope rusty is wrong why didnt u just put them in the stock holes that are already there?
Old 03-10-2008, 01:45 PM
  #22  
JAX FLYING REBEL
Member
Thread Starter
 
Join Date: Jan 2008
Location: JACKSONVILLE, FL
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Default RE: 35% Sukhoi - DA85 Build

Because the stock holes were too big for my switches and I didn't like where they were located. I'm not using the charging switches for the RX. The 9100 has a proprietory switch and I'll be using individual charging jacks for my batteries with a Ion cube.
On an unrelated note, I think this bird will fly better than my 33% Extra. I did the maiden on that bird and had to dead stick it in on my first flight. I got passed the nervousness of that first flight after I greased it in on the grass. The ailerons were pretty sensitive and the plane definitely stays where you put it. However, actual flight was very similar to the simulator. I'm still going to buddy box with one of my friends in the club who has a lot of time on the Wild Hare Extra. Anyway, that's all I want to comment on since this is a build thread.
Old 03-10-2008, 01:53 PM
  #23  
JAX FLYING REBEL
Member
Thread Starter
 
Join Date: Jan 2008
Location: JACKSONVILLE, FL
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Default RE: 35% Sukhoi - DA85 Build

Grotesque Bass,

No I painted the firewall and the front inside of the fuse. I dont think that little bit of spray coating will add a serious amount of weight. That 85 should still pull that plane around with no problems.
Old 03-10-2008, 02:00 PM
  #24  
JAX FLYING REBEL
Member
Thread Starter
 
Join Date: Jan 2008
Location: JACKSONVILLE, FL
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Default RE: 35% Sukhoi - DA85 Build

Well guys, I'd love to sit here and discuss building techniques all day but I have a real job to hold down here. I'll post some pics tonight once I get my radio in and finiish up programming my servos. Done with the wings so I will try to set my elevators tonight. I have another project I'm working on - R&R a busted throttle on my O.S. 1.6 so I can get my Extra back up.
Old 03-11-2008, 08:25 AM
  #25  
JAX FLYING REBEL
Member
Thread Starter
 
Join Date: Jan 2008
Location: JACKSONVILLE, FL
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Default RE: 35% Sukhoi - DA85 Build

Well I got the ignition switch and the DA in last night. I was able to use a charging switch which allowed me to use the existing cut-out on the starboard side of the fuse. I will mount my ignition module on the rt side of the engine box in some black foam that I got from Lowes. Its the stuff you use on plumbing. I'll be mounting my RX next then setting my elevators and rudder last. I'll mark my CG on the wing tips and leave the batteries and rudder servo loose until I can position them to make her slightly nose heavy.

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright 2021 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.