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1/2A Nut's

"Speedy Teedy .020"



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Scary stuff I was wincing in fear!

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Re: Scary stuff I was wincing in fear!

Post  1/2A Nut on Thu Sep 27, 2018 11:22 pm

Hahah Dave, yes the idle was a bit high via the exhaust throttle,
I like the transition when the throttle was opened up all the way, a shocker when first watch
the video back. Still one of my favorite vids. I also like running boats I have three 1/2A boats
and a 4 stroke engine in a outrigger hydro can see them run on my youtube channel.  

Here are two of my designs:

OS FS .56 alpha engine - the only rigger
on youtube powered by a 4 stroke engine.


Picco .05 with a Profi tuned pipe
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Re: Scary stuff I was wincing in fear!

Post  Surfer_kris on Fri Sep 28, 2018 3:17 am

1/2A Nut wrote:See pic anyone besides myself know what I have here  Eyebrows

It looks like one of Bob Mattes reworked ones?
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Re: Scary stuff I was wincing in fear!

Post  1/2A Nut on Fri Sep 28, 2018 10:10 am

Bingo yes Kris your spot on Thumbs Up , also Sal Taibi produced the aftermarket tank, capacity 5cc
vs the stock plastic tank of 7.5cc
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Re: Scary stuff I was wincing in fear!

Post  1/2A Nut on Sat Sep 29, 2018 1:22 pm

This is now the most modified TD.020 I have for the NANO's next flight test.
Will do a bench test of this setup next. Compression has jumped up quite a bit with the Nelson plug.
Previous bench test hit 103 mph pitch speed / 4.23oz thrust / best static peak hit 24.2k with a modified HQ Prop 3.6 x 4.5


Upgrade List:
- Muffler with pressure tap
- GG's Radial Mount
- KK Needle to Cox valve assembly
- EX Model Engines Carb body
- Bob Mattes glow plug adapter
- Nelson insert flat coil plug
- Ron Valentine custom sized TD .020 bullet spinner (by request)



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Last edited by 1/2A Nut on Mon Oct 01, 2018 4:02 pm; edited 6 times in total
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Re: Scary stuff I was wincing in fear!

Post  1/2A Nut on Sat Sep 29, 2018 7:18 pm



Published on Sep 29, 2018

Nano TD.020  Nelson Flat Coil Plug / HQ Carbon 3.6 x 4.5N Prop
Static Hold: 24,870 rpm / 106 mph Pitch Speed / .083 hp / 62w
Static Peak: 25.113 rpm /107 mph Pitch Speed / .086 hp / 64w
4.6oz thrust .Bob Mattes Glow Plug Adapter / 30% Nitro / 20% oil
Ran out of fuel but tweaked the NV enough to see what it can do in time.



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Last edited by 1/2A Nut on Mon Oct 01, 2018 3:59 pm; edited 2 times in total
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Re: Scary stuff I was wincing in fear!

Post  rsv1cox on Sun Sep 30, 2018 7:00 am

1/2A Nut wrote:Thank you Dave! Thumbs Up

I had to modify it from a cox car muffler. (See pic) the front exhaust port is blocked off with a brass shim.
I converted the engine into a FIRE TD .050 To improve flow I filed out the header exit which in stock form is suppressing
quite a bit. A good manifold design with a more breathable header will only improve things, I imagine another 800+ rpm static.
A extension was put on the header to get 9.2" MRP. The Galbreath glow plug adapter and Nelson plug helped seal the deal with
a increase of 2,907 rpm over the first test with a stock high compression plug. The bench test needed the 4x4.5 to get on the pipe.
I would not dare try to fly with it as rpm will jump up 5k+

Published on Jul 2, 2016
Best level pass 143mph / per prop calc / APC 5.25x6.25E
Wavescope: 232.07 kmh / 144.2mph /down wind  / 21,960rpm
The reading was taken at 1.52mins into the vid. Temp 96F
Static 17.1k rpm at launch / 9.52oz / 101mph / .167hp / 125w
30% nitro / 20% castor / 31.5 inches 106 Sq. In. wing / 11.7 oz RTF

I am amazed at your coordination, eyesight, and ability to follow that speeding bullet and keep it in the air.

Bob
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Re: Scary stuff I was wincing in fear!

Post  1/2A Nut on Sun Sep 30, 2018 1:01 pm

Thank you Bob! Thumbs Up
Throttle is the trick fly them till you can keep up with it wide open. Goal is smooth passes
in front of the cam without over controlling the plane and scrubbing off the apex speed.

Today I scared myself again! The run was brief after a few starts setting the
NV to feed the thirsty engine I managed a brief run to check rpm, brief as
it was very loud for a TD .020!

- Bob Mattes reworked engine (shimmed cylinder for best exhaust timing and piston deck clearance)
- Nelson flat coil plug and adapter
- Sal Taibi FF 5cc CNC aluminum fuel tank
- Yang Guici CNC aluminum carb body
- Stock NV
- 30% nitro / 20% castor

Open exhaust test with the Bob Mattes custom Tee Dee .020 FF engine:
HQ Carbon blend 3.6 x 4.5N
Static 29,554 rpm / 126 mph pitch speed / 6.7oz thrust / .14hp / 104w
[i][size=10]The narrow prop is fooling the thrust calc program so HP/Watts are going to be off.



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Re: Scary stuff I was wincing in fear!

Post  gkamysz on Sun Sep 30, 2018 8:34 pm

This might work?






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Re: Scary stuff I was wincing in fear!

Post  1/2A Nut on Sun Sep 30, 2018 8:51 pm

Thumbs Up
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Last edited by 1/2A Nut on Mon Oct 01, 2018 11:18 am; edited 5 times in total
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Re: Scary stuff I was wincing in fear!

Post  Ken Cook on Sun Sep 30, 2018 9:25 pm

Brad is the manifold set up to accept the pipe you use? My manifold is very similar on my piped TD. However, the only pipe I have is for the CS .049/.061. The problem with mine is that the outside diameter is the same size as the OD of my manifold. Probably not a issue if I used a silicon connector to join them. I just noted that my manifold internally has a o-ring groove within it to accept the pipe internally. In addition, is this manifold designed to utilize a standard dual exhaust cylinder? My KK versions have one exhaust cutout in the rear. I assume one needs to shim the cylinder to index the exhaust cutout to the rear? Ken
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Re: Scary stuff I was wincing in fear!

Post  1/2A Nut on Sun Sep 30, 2018 9:46 pm

Hi Ken,
I have requested the Profi ID to fit the header ID, go back a page you will see some base line measurements.
Yes the O ring trick is the clean look for sure either outside or inside. I like the silicon tube as the pipe
does not disappear in the grass. I still use a secondary method to keep the pipe in one spot various ways
such a stinger mount.

What is the measurements of the CS pipe?

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Re: Scary stuff I was wincing in fear!

Post  Ken Cook on Mon Oct 01, 2018 7:39 pm

I will have to provide the measurements when I get it out. I purchased it and the half pan for the CS .061 from Bill Hughes a control line speed flyer. Here's his info


B & L HOBBY SUPPLIES, INC
113 North Chase Ave., Bartlett, IL 60103
G/Z .049/.061 Engines; sales, service & parts.
Engines available in both normal and pipe timed configurations. (Bill Hughes)
e-mail: williamhughes4@att.net 630-736-6036
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Re: Scary stuff I was wincing in fear!

Post  1/2A Nut on Mon Oct 01, 2018 8:21 pm

Thank you Ken Thumbs Up , info had to be removed for now 8mm ID / 10mm OD was the current design spec for the header will
have to keep things low key till the machinist is ready to batch run. You can modify from there to suit your particular
pipe. What I would like to see done is a good all around fit for the common 1/2A pipes.

I have a CS .061 tested with a Profi pipe. 5 1/2A tuned pipes on hand some on planes one just for the CS engine
Always one spare for bench testing.



Published on Nov 24, 2017

CS .061 / Nelson Plug Med. / Profi .8cc Tuned Pipe / APC 4.5x4
Best Peak 25,193 rpm / .188hp / 140.3w / 12oz thrust / 96 mph
Hold peak 25,052 rpm / 25% nitro / 20% oil blend
8.75" Mean Reflective Point / "center of piston to 2" from end of stinger.
Needle Valve 3.75 turns out due to no pressure tap. Left a bit rich as it is new old stock.
105.7g as shown with pipe (I had to cut out the spinner to fit the APC prop)
4.75 x 4 would make a good sport / speed prop in the air, when it happens
I want to try the 4.5x4 in the air suspect it will do around 32k for RC use.
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Re: Scary stuff I was wincing in fear!

Post  1/2A Nut on Thu Oct 04, 2018 9:50 pm

FYI Ken left a message with Bill two days ago on his voice mail no response yet.

RC Plane

And had a carb body issue it came loose in this vid attempt but still shows the rpm.
The CNC TD .020 body with the spring post is a loose fit does not mimic the crank case dia. for
a snug tight fit. The extra wiggle room makes it easy to come loose with only the collar doing
100% of the work.

Published on Oct 2, 2018

Testing GMark carb add on with Nelson plug.
Quick run it is very loud with this kind of rpm open exhaust.
I did a couple of quick runs with it the carb body came loose
Shown 29,392 rpm / 125 mph pitch speed /6.4oz thrust can spin the
3.6x4.5N at 30,604 rpm /130.4 mph /7oz thrust!  Bob Mattes FF reworked
TD .020 with a G-Mark carb and GG backplate /Valentine .020 bullet spinner.
Needs a bit more prop for safe realistic unloaded rpm around 34k
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Re: Scary stuff I was wincing in fear!

Post  Surfer_kris on Fri Oct 05, 2018 1:12 am

The CS .061 came in two versions, one timed for using a pipe and one for open exhaust, which one do you have?

I have one of the non-piped ones, and it did around 23000rpm on the APC4.75x4 using 10% nitro. That's about 1000rpm up on a standard Norvel .061 engine, so I wasn't that impressed considering the extra weight that the CS carries....

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Re: Scary stuff I was wincing in fear!

Post  1/2A Nut on Fri Oct 05, 2018 2:28 am

If you have a CS tuned pipe or a 1/2A pipe in general try it again. The 4.75x4 is ok
for unloaded flying but will not do so hot on the bench. The timing is too high for
open exhaust with that prop. I recommend trying the 4.2x4 on the bench a high
timed engine has no torque without the aid of a pipe.

I do have the specs on my CL version:
Exhaust - 182 deg.
Transfer - 130 "
Intake - 178 "
Stroke is 10 mm

I will have to check the engine it was a simple run it and see how it goes with the 4.5x4.
In hindsight I should have ran the 4.2x4 on the bench. I have been told the cheap prop of choice
for most was the APC 4.2x4 for flying with the CL version. The engine was left a bit rich as I
had low time on the engine prior to the vid.

Looking at my vid:
Best Peak 4.5x4: 25,193 rpm / .188hp / 140.3w / 12oz thrust / 96 mph
This will unload in the air all over 31k rpm / 118 mph.
I have better props for speed 4x5 at 29k / 137 mph
I have 4 CS engines Sport RC with side muffler CL with side muffler - both no bearings
Then FIRE with bearings CL came with a Nelson plug and this RC version in the vid.
it came with a insert plug, I changed it to a Nelson head.


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Re: Scary stuff I was wincing in fear!

Post  Surfer_kris on Fri Oct 05, 2018 6:04 am

Sounds like you have the one that is timed for a tuned pipe, it will be improtant to get that right in order get the most out of the engine. Mine is the CS/G&Z .061N with "normal" timing, I haven't checked how much that is.

Have you tried any of the CS "sport" engines yet?
I wrote a long thread on RCU 1/2A forum at the time when these first came out (+10years ago I guess), it was not a positive experience but they can be made to work...  Wink
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Re: Scary stuff I was wincing in fear!

Post  1/2A Nut on Fri Oct 05, 2018 7:31 pm

Yes I remember the thread you had a bad crank case casting that leaked.
The small RC carb was the initial draw for me to buy the sport RC version then the CL version to
round out the collection. I ran the RC sport up once it seemed ok at the time, I was more interested
seeing how well the RC carb worked fully prepared to rob it for use with CL bearing FIRE version.
RC carb currently on another engine.

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Re: Scary stuff I was wincing in fear!

Post  1/2A Nut on Sun Oct 07, 2018 11:26 pm

I have been looking at a reasonable size fuel tank for the more thirsty piped TD engine.
In the posted vid I was using a 2oz tank it was pulling that tank down fast. Clearly a
1oz tank will not do for an acceptable flight duration. As some may know I have been
making my own tanks for small IC projects to save weight and to control the amount
of fuel for high rpm flying. Here is my latest tank project in the making. I bought 4
aluminum bottles from across the pond to try out. As shown 50cc / 1.7oz capacity.
Enough fuel to take care of a stock TD .09 if need be. A must for a TD .050 on a pipe.
The Nano .050 gets 6 mins on 1oz at 27k unloaded at 32k unloaded with a pipe I would
be lucky to get 4.5 mins in the air after startup tune and toss. I would like at least a
7min flight. 11.6g no hardware bare aluminum tank, tested for function with a plastic
end cap, have ordered a aluminum assembly to step it up to the next level with no chance
of it cracking over time and it just looks better with an all aluminum finish. One other thought
aluminum tanks cool the fuel a benefit that will make the fuel more dense -aka more power:brows:
Drag racers use fuel coolers that compact molecules gives them a edge. In the summer months I
always fill my gas tank in the early morning you get more for your money rather than during the
heat of the day.

Comparison to a 1oz tank:

Feather weight considering this is a 1.7oz tank, less a 1/2A size clunk.

Will use this kit to finish out the tank with the kit comes in I will follow up with a final pic.
Note the modification needed. I have 5 more bottles currently. CNC cap lids .92" ID x 1" OD x .2" skirts.
The will cut cost over the Sullivan kit and fit the tank perfect as a traditional capped off tank.  

My current arsenal of super feather weight DIY tanks:

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Re: Scary stuff I was wincing in fear!

Post  Surfer_kris on Mon Oct 08, 2018 1:17 am

The man problem, to me, with the commercial tanks is that heavy bung/stopper that they all use (appart from Hayes). So for me eliminating that heavy part is the main drive for making my own tanks. The only thing that's needs a bit of weight is the clunk it self, but even that can be made smaller and lighter if one uses a smaller or thinner walled silicon tubing for it.

For the large fuel tanks I don't bother to make my own clunks anymore and simply go with the sintered copper ones. Here is an example of a 4oz tank that weights about 20g including the clunk, this is possible by not using any other rubber seal than the fuel line itself:


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Re: Scary stuff I was wincing in fear!

Post  1/2A Nut on Mon Oct 08, 2018 2:13 am

Thank you for sharing Kris,
I see no cluck or a pressure tap on the muffler was that the final setup?
A single short piece of med. fuel line can weight a ton from rear of tank to
carb adds some weight fast. I prefer aluminum tube in my small tanks in
fact there is no reason to use brass unless you have a 25 size engine and up.
Note a stock Du-Bro S-2oz tank a breath away from 26g with clunk.



Here is your typical stopper assembly weight with the brass.
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Re: Scary stuff I was wincing in fear!

Post  Surfer_kris on Mon Oct 08, 2018 10:19 am

Well, that's an ugly/heavy fuel line...

I'm not using commercial fuel lines for critical applications. One can simply buy much better pure silicon tubes on ebay, comes in all metric sizes down to 1 mm in wall thickness. Works great for our small engines and even up to .10 engines. So thin walled silicon tubes, no brass or other metal tubes needed, no bungy either. Instant 10g reduction (roughly for a three line set-up) and no risk of pinched holes in the fuel-lines (as there is no metal to pinch against). Smile

Here is the current set-up, I now use an OS .10FP with pressure fead from the muffler, instead of the .10FSR I used at first. The pressure feed is very good on these engines, and it idles reliably at around 3000rpm.

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Re: Scary stuff I was wincing in fear!

Post  Dave P. on Mon Oct 08, 2018 11:17 am

As long as the topic of fuel tanks has come up, I have a couple things you guys might be able to help me with.

I'm in the kit cutting phase of a 50% reduced RCM plan for a flying wing called the T-Bird. The .46 size has plenty of room for a 10oz tank, but the 1/2A version is really tight. About an inch of vertical room for three inches aft of the spars. My plan right now is to use my old after-run oil bottle with the needle cut off flush and two pieces of aluminum tubing JB welded in and a short piece of brass tube for a clunk.

First, does anyone see anything I might be missing or that I might do differently concerning the tank?

I was going to use a Medallion with a throttle ring but I'm thinking right now about converting one to a TeeDee cylinder and 05 carb and drilling out the pressure tap. Any thoughts about that?

Thanks in advance!
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Re: Scary stuff I was wincing in fear!

Post  Dave P. on Mon Oct 08, 2018 11:26 am

Pictures didn't load ...

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Re: Scary stuff I was wincing in fear!

Post  Dave P. on Mon Oct 08, 2018 8:01 pm

Sorry I hijacked your thread Brad.  I should have started a new thread for this, which I will do shortly. Thanks!
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Re: Scary stuff I was wincing in fear!

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