bobripley

Hello Bob,

Thank you for the suggest but after three plus years working on one airplane I think it will be a good long while before I do another T-34. Mike Barbee's 36% scale T34 was pretty much a scratch build using Bob Patton's molds to make the fiberglass fuselage.

Ripley

bobripley

Hello Carl, and AaRahn,

I ran the engine and custom muffler on my T-34 and here is a summary of the results that I post on RCScalebuilder.

Success!! The Super Tigre G2300 MkII with the Perry carburetor is a great combination for this airplane and my cooling concerns were unfounded.

Test #1 Base line test with cowl OFF
• Propeller used: Vess 17 x 8s
• Max RPMs: 7600
• Idle RPMs: 2000
• Engine Temp at the head around the glow plug: 205 degrees
• Engine Temp at the front of the head: 165 degrees


Note 1: The first run is where I adjusted the high speed needle, looked for leaks around the muffler and header and generally just check everything over. Once I peaked the high speed needle valve it was richened a bit for a max RPM reading of 7500. No adjustment was needed for the low speed needle valve.

Note 2: Fuel drips from the carburetor a bit when the engine is not running but that is due to the slightly high fuel tank location.

Note 3: I think that there might have been a slight exhaust leak between the engine muffler mounting flange surface and my header. I replaced the thin paper gasket that I made with high temp rubber gasket from a tube during the post engine test inspection.

Test #2 Cowl mounted on the airframe.
• Propeller used: Vess 17 x 8s
• Max RPMs: 7560
• Idle RPMs: 1980
• Engine Temp at the head around the glow plug: 145 degrees
• Engine Temp at the front of the head: 143 degrees

Note 1: It is really hard to get a temp reading of the head around the glow plug with the cowl in place so that reading is the highest value that I measured. The temperature reading for the front of the head was measured with the engine running at full RPMs and taken with the laser temp gun pointed through the cowl opening. In case you were wondering, yes I had the plane well secured with a tether around the tail group.

The engine ran beautifully with no sign of overheating and I did not touch the high speed needle valve at all. The baffling worked perfectly!!

Note 2: The engine actually runs cooler with the cowl on.

Test #3 Cowl mounted on the airframe with static thrust test.
• Propeller used: Vess 17 x 8s
• Max RPMs: 7340 - 7500
• Idle RPMs: 2070
• Engine Temp at the head around the glow plug: 156 degrees
• Engine Temp at the front of the head: 140 degrees
• 14 lbs static thrust

Note 1: The engine defiantly runs cool with the cowl in place and with this prop, plus the sound of the engine/muffler combination through the exhaust ejector has a low throaty quality to it.

Note 2: The thrust test was crude at best. I used a 50lb spring type fish scale with one end tied to my stake in the ground and the other end of the fish scale attached to the tether on the tail group of the T-34. I highly doubt that the 14lb thrust test was accurate but it was good to use as a comparison when I tested the other props.

Bottom line..... baffling the engine compartment worked far better than I had hoped.

Next will be the maiden flight in about two weeks.

Ripley

bobripley

Hello,

I did the final check of the CG this evening with the pilot on board. Check.

Set up the high and low rates with expo for aileron, and elevator. Check

Mixed a slight amount of down elevator trim for half and full flap deployment. Check

Made sure that left and right control inputs actually moved the ailerons and rudder in the correct direction. Check

Balanced a couple of spare props and that's it. Tomorrow is the maiden flight of this three year project

Ripley

bchapman

Hi Bob,

I'm almost ready for my maiden as well. Good luck and I look forward to hearing how it went!

Brian

bobripley

Hello Brian,

Will do sir. How did yours come out? Any pictures?

Ripley

bchapman

Bob,

I'll post some pictures tomorrow. Mine sure didn't come out as nice as yours, but I'm pretty proud of it for my first scale plane. I didn't end up putting the cockpit kit in yet, because I'm getting it ready for a local event. But, I did manage to get the landing gear doors operational with the help of your kit and it looks great. So much more to do, but I really want to start flying it. I'll work on it as I go.

All I need to do is re-install the engine, check the CG and do some last minute checks. I didn't add in any trim adjustments with the deployment of flaps, so I'm interested in hearing if you think it's really necessary.

Talk to you soon,

Brian

bobripley

The good news is the damage was minimal and the repairs should be completed by next weekend. The bad news is the maiden flight is now scheduled for May 12th.

The intent yesterday was to first do a low and high speed taxi test followed by the maiden flight. Further, if the T-34 lift off during the high speed run I would pull back the power, let it settle back down on the runway, and roll out to a stop proving that it did have enough power for the test flight to follow. Sure enough, 300' into the high speed taxi run the plane lifted off about a foot so I pulled back the power and it set back down on the run way. Unfortunately, the T-34 rolled off of the end of the runway, on to our mowed area, and then into the tall weeds where the left wing hit a small sapling. Besides the damage to the leading edge, I cracked the fuselage by the exhaust ejector, bent the pivot pin for the nose gear, and of course broke the prop.

I do know that the Super Tiger 2300 has plenty of power for this plane and it doesn't slow down much on paved runway. Lesson learned, next time out the take off will be on our paved runway but the landing will be in the parallel and longer grass runway.

Ripley

bobripley

Hello all,

We did our second test flight on Sunday and the Super Tigre 2300 is a great match for this 20lb airplane. It has plenty of power and pulled the T-34 along in scale fashion. I probably should have picked a better day for this second attempt because it was cold and very windy but the my T-34 didn't seem to care. I did have an incident however and lost all air pressure in the retracts when the nose gear air line came in contact with the exhaust manifold and burnt a hole in it (an insulating tube crept out of place thus exposing the airline). This resulted in collapsed landing gear and a runway belly landing. The steel tube exhaust ejectors protected the bottom of the wing and I suffered only minor scraping of the right wing tip and shedding of the nose gear doors. All will be repair before the Mint Julep in June.

bobripley

Hello All,

I entered my T-34 at the Bob Evans Farms 25th anniversery R/C scale contest last weekend and here is a link to a YouTube video that a fellow contestant took of my first round on Saturday. I was very surprised and pleased to learn that I had won the pilot's choice award for best airplane.

http://www.youtube.com/watch?v=sa0AgMmPlEM

Ripley

bobripley

Hello Again,

The TopFlite T-34, all dolled up and with the Super Tiger 2300 under the cowl has proven to be a competative contest aircraft. Mike Barbee held the 1st annual Columbus Scale Class R/C scale contest and Scale Masters qualifer last weekend and I happy to say that the T-34 took first place in the Sportsman Sport Scale category. "Little Debbie" received 93 out of 100 static points on Saturday and Sunday I posted my two best flight rounds with a 97.5 for round three and 97 for round four. Even at 20 lbs the T-34 flies very well and slows down nicely for dirty fly bys and landings. It is not TeleMaster Trainer slow but very comfortable none the less. The fully cowled Super Tiger 2300 has performed flawlessly without any hint of over heating. Needless to say, I am very happy with this plane.



Ripley

tailskid

My Feedback: (34)

Congrats!!!!!

bobripley

Thank you. Winning Sportsman Sport Scale was the good news. The bad news is I have to move up Expert Sport Scale now. Which means flying against the big boys in R/C Scale competition.

That's fine but it does mean that I will have to improve things on my aircraft to move the stactic points up a few more points. A 93 is not a competitive mark at the expert level.

Ripley

Texan2

My Feedback: (4)

Almost done with my mentor. All there is to do now is install my receiver, gear doors, and cockpit.

bobripley

Hello Carl,

It looks good. What engine did you finally settle on for your T-34?

Ripley

Texan2

My Feedback: (4)

The super tigre 2300

ced733

Hi all !

Here is mine, maiden today in a perfect weather.
Very easy to fly, smooth on commands, first take off with flaps, about 100m run. I suppose due to a light nose down attitude.
Landing with full flaps, very easy and short.
A real pleasure to fly !

Full electric, SBUS, telemetry.
Century Jet Retracts
Landing lights, strobes
weight 7.6kg with all batteries
ESC K-FORCE 120A-HV
Turnigy Aerodrive 6354 260 kv
Lipo 8s 5800 25C
Prop 2 blades 17x8
About 12mn with 75% throttle, that's perfect !

Texan2

My Feedback: (4)

We've finally finished. now our only issue is our prop is dangerously close to the nose wheel. We are using a 17x8 on that G2300. Can we afford to go down to about 16x10 maybe.

mmarion

Hello everyone.
After many rebulds of used kits and ARF, I am joining the Kit Builder with my TopFlite T-34B Mentor.

With this kit, I plan to use:
- a Saito FG-21 Gas 4-stoke (20,9CC) with Ignition System (Hope it fits well) ... will check on proper venting
- Spektrum AR8000 RX and some telemetry (Temp and RPM to start with)
- Robarts 630BNZ AIR Retracts (The price of the Electric equivalent is absurd!)
- SonicTronic Tricycle Retract Hinges (mechanical)
- Fiberglass Specialist Cowl and Tail for this kit
- TopFlite T-34 Detailled cockpit with (Hopefully 2x WarBirds Pilot)

As I am Canadian and wish to be slightly different I and targeting the 1955's RCAF Scheme (Canada had 25 of the T-34A
[TABLE="width: 100%"]
[TR]
[TD] (License-built from Beechcraft by Canadian Car & Foundry)
[/TD]
[/TR]
[/TABLE]
[TABLE="width: 100%"]
[TR]
[TD="class: prodid"][/TD]
[TD][/TD]
[/TR]
[/TABLE]
... all Aluminum with Black Top. Ruddder, Elevator, Flaps and Ailerons are Yellow.

Here is a link ==> http://www.airic.ca/assets/images/gen20127142266a.jpg

I have devoured the entire thread and will have some planning questions for now:

Q1) Any Recommendation for lighting .. suspect that in 1955, Stobe with where not used.

Q2) Decals: As mine are a bit rare :-) . are you guys using water based, buying from a specialized Decal Shop or making your own?

Q3) I plan to install the Air Reservoir in the middle section of the wing .. To whomever who've done this, do you have a large hatch to access it back?... I am always worried about AIR Hoses maintenance and leaks.

Q4) Because of weight and the fact that I never glassed that large of a project, I am tempted to simply cover it with some resistant material (looking at Solarspan vs Monokote) .. Any comments?


Any other feedback is welcomed

Thanks

ir3

My Feedback: (42)

Sorry Jerry, not meaning to steal the thread but I have a possible answer for mmarion. If I am not mistaken, the difference in the price for the air retracts versus the electrics from Robart is not that far apart. They supply the controller for the electrics. Think about it, no air tanks, no pumps, no valves, no leaks and as a bonus you get to control the timing of both the speed of the landing gear and the door open/close functions. It is a lot more to scale and no headaches other than recharging the battery for the controller. Unless I missed something it seems to be a win-win situation.

Just my 2c and good luck with your build.

BTW, the T-34 on the thread are fantastic. I was thinking of a T-34 also while I was working on the restoration a North American PBJ to fly. The crew chief owns a T-34 and I was going to do in his livery. But, not being on the project any more, that idea was scratched. In any case, the T-34 is a great subject for modeling.

Cheers,

IR3

mmarion

Hello IR3

In the US, AIR vs Electric might be closer in price ..
The fact is that Robart will sell thru GreatPlane, HobbieZone and other distributor its AIR Retracts and buyers benefits from this ... but it seems that you can only get the Electric thru them.

So complete AIR at abt $500 Cdn vs Electric at $580 US + transport 60$ + abt 15% exchange rate with Cdn $ = abt $740

I was hoping that Electric would be closer to AIR, but not sure that Robart want to promote it as much as we tough.

But your are right AIR need to be check again and again .. Cross Finger and Touch wood .. did not happen .. YET :-)

builttocrash

Subbed. Going to start mine here soon.

coderman

Anyone building this plane in 2021 and/or have a collection of detailed photos? Wondering what the best 4 stroke engine to drop into the plane that's currently available as well. I have both an OS FT160 and a Saito FA125 converted to spark ignition on glow, which gives a bit of extra "guts" to the engines compared to stock at least. Wondering if the 125 will fit with some clever angling of the motor? I know the FT160 won't, but the valve covers at least look cool

rowdog_14

My Feedback: (5)

I know this thread is not hot now but just picked up a never flown everything never used TF T-34! Air Robart Retracts, OS 91fx. Just need to add my battery and receiver.

adreliable661

My Feedback: (12)

Thanks, but not what looking for. Got mine built already. Yours is beautiful by the way.

rowdog_14

My Feedback: (5)

Thanks but mine actually was not in reply to you. Just a standard forum post.