Go Back  RCU Forums > RC Airplanes > "1/2 A" & "1/8 A" airplanes
Reload this Page >

Td .051 powered speedster

Notices
"1/2 A" & "1/8 A" airplanes These are the small ones...more popular now than ever.

Td .051 powered speedster

Old 11-12-2020, 01:35 AM
  #26  
Pond Skipper
 
Pond Skipper's Avatar
 
Join Date: Dec 2009
Location: Texas, TX
Posts: 2,794
Received 3 Likes on 3 Posts
Default

The last of Doug's adapters paired with Nelson plugs are being sold off on ebay incase you want a fresh shiny
https://www.ebay.com/itm/Cox-049-051...IAAOSwA9xfrHpb

The aluminum carb body helps keep the case cooler / radial mount is the icing on the cool cake it equals more rpm EX Models has the carb body on ebay.
https://www.ebay.com/itm/Cox-049-051...gAAOSwImRYjkBw

Received this MK II from Doug completing a nice VA .020 / MK I and II collection.
Dunno if I will do anything more then run them up for a power check comparisons to what I get out of the TD's and others.
CS sport engine mufflers work with the MK's / only requires 1 tap for a hex bolt.







Old 11-12-2020, 09:59 PM
  #27  
Pond Skipper
 
Pond Skipper's Avatar
 
Join Date: Dec 2009
Location: Texas, TX
Posts: 2,794
Received 3 Likes on 3 Posts
Default

The .05 car engine works well with the long tail moment and the extra wing.
When I had the TD .05 RC on the nose the weight of the Cox muffler kept the CG in check.

Top views help hone down the next version for TD proportions that will march forward with additional speed.
The reduced load will allow the next aggressive pitched prop.



Last edited by Pond Skipper; 11-12-2020 at 10:09 PM.
Old 11-13-2020, 12:55 PM
  #28  
combatpigg
Senior Member
Thread Starter
My Feedback: (3)
 
combatpigg's Avatar
 
Join Date: Nov 2003
Location: arlington, WA
Posts: 20,016
Received 5 Likes on 5 Posts
Default

Those are great looking planes..!
What are they made out of..?
The .020 TD showed up and Doug G sent a bunch of "extras" to go along with it...so I'm very glad you pointed out that he had this for sale.
My first attempt at a FG lay up with the new TD Speedster fuselage molds ended up too heavy. 2 layers of the typical FG cloth you would find at Lowes [6 oz?] ended up way too heavy. The fuselage would have ended up weighing 5 or 6 ozs.
I could try a single layer of the same cloth, or shift down to some 1.5 oz cloth I got from Sig and give that a try.
Old 11-13-2020, 09:34 PM
  #29  
Pond Skipper
 
Pond Skipper's Avatar
 
Join Date: Dec 2009
Location: Texas, TX
Posts: 2,794
Received 3 Likes on 3 Posts
Default




Note the fuel tank is glued into place to improve strength.
Awesome Doug hooked you up good to hear Chuck!
Bummer about the glass work being too heavy for 1/2A
Last pic show percentage changes after flying the N III
to get more speed out of the NX.
Old 11-13-2020, 10:31 PM
  #30  
combatpigg
Senior Member
Thread Starter
My Feedback: (3)
 
combatpigg's Avatar
 
Join Date: Nov 2003
Location: arlington, WA
Posts: 20,016
Received 5 Likes on 5 Posts
Default

Originally Posted by Pond Skipper View Post



Note the fuel tank is glued into place to improve strength.
Awesome Doug hooked you up good to hear Chuck!
Bummer about the glass work being too heavy for 1/2A
Last pic show percentage changes after flying the N III
to get more speed out of the NX.
Thanks for the inside look..! I like the idea of using the tank for strength.
I think the least wing area I ever tried with TD .049 power was 105"...but that was with a heavier fuselage than what you show with your NANO planes. Back then I also used a cardboard tube for a safe place to keep the bladder but this was a waste of weight and time. Nowadays I just provide a drain hole in the floor of the fuselage and cross my fingers for luck.
Been thinking about what to do with the .020. A tiny PBF and of course a tiny C/L plane for backyard flying come to mind.
Old 11-13-2020, 10:49 PM
  #31  
Pond Skipper
 
Pond Skipper's Avatar
 
Join Date: Dec 2009
Location: Texas, TX
Posts: 2,794
Received 3 Likes on 3 Posts
Default

The wing gets 1/64th ply skin center wing treatment top and bottom with spruce front and back edges.
I use rubber bands as there is no space for bolting the wing on inside / fuselage is skinny with only room
for the gear. Proportions drawn around the gear. Looks like I went with the thicker ply sheet for belly landings
tail reduced to the thin stuff. Sticky back carbon pattern trim used to keep the servos in the wings. Servos held
well by having the cutouts with no slop. UVA and oil resistant fishing rubber bands.














Old 11-14-2020, 09:51 PM
  #32  
combatpigg
Senior Member
Thread Starter
My Feedback: (3)
 
combatpigg's Avatar
 
Join Date: Nov 2003
Location: arlington, WA
Posts: 20,016
Received 5 Likes on 5 Posts
Default

I like the carbon fiber covering. Does it behave like regular monokote..?.
I just got done laying up another pair of fuselage halves. This time with 1 layer of the heavy cloth and 1 layer of light weight [1.5 oz] cloth. 60 ccs of epoxy resin. Tomorrow morning we'll see what we got.
Old 11-15-2020, 09:29 PM
  #33  
Pond Skipper
 
Pond Skipper's Avatar
 
Join Date: Dec 2009
Location: Texas, TX
Posts: 2,794
Received 3 Likes on 3 Posts
Default

Yes it's not bad to work with, thin and strong - low weight compared to Neon Monokote made by Hanger 9.
I will dig for a finished weight wood bare for comparison to the next glass fuselage.

update for your comparison:
26.4g -.93oz competed hardwood box all sides and firewall.



Last edited by Pond Skipper; 11-16-2020 at 01:37 AM.
Old 11-16-2020, 11:19 PM
  #34  
combatpigg
Senior Member
Thread Starter
My Feedback: (3)
 
combatpigg's Avatar
 
Join Date: Nov 2003
Location: arlington, WA
Posts: 20,016
Received 5 Likes on 5 Posts
Default

That's good to know about the CF covering. .
Here's some progress. I put a couple of ducts on either side of the fuselage



for the exhaust gas to exit.
Old 11-16-2020, 11:49 PM
  #35  
Pond Skipper
 
Pond Skipper's Avatar
 
Join Date: Dec 2009
Location: Texas, TX
Posts: 2,794
Received 3 Likes on 3 Posts
Default

How are you liking the weight so far?
Good to see some fresh air to the venturi, looking good Chuck!
Sound should be interesting via exhaust exits.

Inverted engine is going to induce a chance for cooler combustion chamber.
That should allow a bit more leaner nv for some extra rpm.
A aluminum carb body would help the top case stay cooler.
For sure will like some castor, will be interesting to hear how
steady the beast runs at full gallop.


Last edited by Pond Skipper; 11-17-2020 at 12:00 AM.
Old 11-17-2020, 12:06 AM
  #36  
Pond Skipper
 
Pond Skipper's Avatar
 
Join Date: Dec 2009
Location: Texas, TX
Posts: 2,794
Received 3 Likes on 3 Posts
Default

Lol look what Mike / MJD has been up too..

Nov 16, 2020



Last edited by Pond Skipper; 11-17-2020 at 12:11 AM.
Old 11-17-2020, 01:03 AM
  #37  
combatpigg
Senior Member
Thread Starter
My Feedback: (3)
 
combatpigg's Avatar
 
Join Date: Nov 2003
Location: arlington, WA
Posts: 20,016
Received 5 Likes on 5 Posts
Default

MJD is moving out pretty good..! My neighbor has a bicycle with a gas engine. IIRC, the gas engine conversion is a kit he installed.
I think the weight of the plane is within reason so far. I'm being as stingy as I know how with the cloth and the resin.
By the end of tomorrow I'll have a better idea about the weight because the plane will be much closer to being done.
TD .049 #2 I had laying around is slightly weaker than TD #1, but a P/L set just arrived from Cox International as well as a package full of the little plastic needle valve seals.
I've got enough junk laying around to put together a half decent TD...I think.
Old 11-17-2020, 01:59 AM
  #38  
Pond Skipper
 
Pond Skipper's Avatar
 
Join Date: Dec 2009
Location: Texas, TX
Posts: 2,794
Received 3 Likes on 3 Posts
Default

The .051 piston / cylinder set I am using with the NX is an old one from the 80's ran in my inboard outrigger hydro.
Lucky for me it was ran with SIG 25%- rpms over 30k whenever it bounced out of the water using a surface drive prop.

Down wind pass 4.3 x 5.5 @ 28,746 / 149.7 mph pitch speed / 143 doppler that's the best I have thus far.
Your the only other pursuing extreme 1/2A RC speed will be a thrill for me to see what you get out of the project.

Given the 28" wing / sq's that will be used and possible savings in fuselage weight this prop would serve well modified.





Last edited by Pond Skipper; 11-17-2020 at 02:19 AM.
Old 11-17-2020, 04:22 PM
  #39  
combatpigg
Senior Member
Thread Starter
My Feedback: (3)
 
combatpigg's Avatar
 
Join Date: Nov 2003
Location: arlington, WA
Posts: 20,016
Received 5 Likes on 5 Posts
Default

Unless I pick up and move to Eastern Washington...049 is the only RC Speed I'll have room to fly.
The neatest little gizmo to have at the field was the "How Fast?" onboard speed indicator.
It was made by "Winged Shadow Systems" but they are out of business, I forget what the space limitations are to fit it on a wing, but I don't think it was feasible to do it on a SWR or I would have tried it. The air sampling tubes need to be X amount of inches away from the prop blast. At the end of each flight it would tell you How Fast? for around $30 or so.

Last edited by combatpigg; 11-17-2020 at 04:44 PM.
Old 11-17-2020, 05:58 PM
  #40  
Pond Skipper
 
Pond Skipper's Avatar
 
Join Date: Dec 2009
Location: Texas, TX
Posts: 2,794
Received 3 Likes on 3 Posts
Default

A good level pass in front of a camera is enough to check rpm quite accurately now with a audio tach app called "RPM Gauge" for android.
Wav. Scope works well enough for a doppler shift reading if blown up to full screen you can get the shift points on the money.
I also have a oscilloscope to read speed passes in hz. to convert.

See results from two methods match up within 1.8 mph 233 kmh = 144.8 mph


Last edited by Pond Skipper; 11-17-2020 at 06:01 PM.
Old 11-17-2020, 07:22 PM
  #41  
combatpigg
Senior Member
Thread Starter
My Feedback: (3)
 
combatpigg's Avatar
 
Join Date: Nov 2003
Location: arlington, WA
Posts: 20,016
Received 5 Likes on 5 Posts
Default

https://www.singahobby.com/index.php...sensor-v3.html

This is what I want....but who knows how much speed it would scrub off a .049 plane..?
Old 11-17-2020, 10:26 PM
  #42  
Pond Skipper
 
Pond Skipper's Avatar
 
Join Date: Dec 2009
Location: Texas, TX
Posts: 2,794
Received 3 Likes on 3 Posts
Default

Nice but no longer in production.

This is still in production, Measures airspeed from approximately 15 to 350 MPH in 1 MPH resolution
Operational Voltage: 3.5 to 9.6 volts
Dimensions: 28x16x10mm
Weight: Circuit board - 4 grams/pitot tube - 3 grams (7g gross)
Calibration: No user calibration required

https://www.ebay.com/itm/12429790326...MaAtXPEALw_wcB

Requires this receiver and a way to retrieve the logged info or a tele TX with real time audio.
https://www.ebay.com/itm/Spektrum-AR....c100008.m2219


I really only care about my perspective from a fixed point / seeing the plane bolt past me down wind.
Ground speed data in front of the camera to share on youtube.

This with the tele rx.
https://www.ebay.com/itm/Spektrum-Sp....c100005.m1851
Old 11-18-2020, 09:23 PM
  #43  
combatpigg
Senior Member
Thread Starter
My Feedback: (3)
 
combatpigg's Avatar
 
Join Date: Nov 2003
Location: arlington, WA
Posts: 20,016
Received 5 Likes on 5 Posts
Default

Today was an OFF DAY for building. I should have left the FG fuselage halves in the mold a few days longer. There are all sorts of sags and ripples. I've been day dreaming of a method where the fuselage can be laid up as a single unit. The mold would need to be 3 pieces that run end to end lengthwise. Pull out the center piece of the mold to free up the outer mold halves. The fuselage design would need to be somewhat conical for the mold pieces to be extracted out the front. Still a Pipe Dream unless I get better with my mold release skills.
I'm also thinking about different ways to make the stab / elevator...instead of the usual 1/8" balsa with iron on covering.

Last edited by combatpigg; 11-18-2020 at 09:29 PM.
Old 11-18-2020, 10:26 PM
  #44  
Pond Skipper
 
Pond Skipper's Avatar
 
Join Date: Dec 2009
Location: Texas, TX
Posts: 2,794
Received 3 Likes on 3 Posts
Default

Awe sorry to hear about the shrinking, carbon tow will stiffen up faster to control the buckling short of heat curing to lock in the shape faster.

Matt black might hide some of it's surface aesthetics.

Old 11-18-2020, 10:56 PM
  #45  
Pond Skipper
 
Pond Skipper's Avatar
 
Join Date: Dec 2009
Location: Texas, TX
Posts: 2,794
Received 3 Likes on 3 Posts
Default

Regarding tail feathers I have tried ply it can be thinner still a bit of foil shaping starting with a thicker piece.
The upshot is stiffer at higher speeds thinner and able to battle tumbles. I use longer tail moments to get
away with smaller tail surfaces. Always foil the surfaces to help the back end sit at speed.
Old 11-19-2020, 04:00 PM
  #46  
combatpigg
Senior Member
Thread Starter
My Feedback: (3)
 
combatpigg's Avatar
 
Join Date: Nov 2003
Location: arlington, WA
Posts: 20,016
Received 5 Likes on 5 Posts
Default

Originally Posted by Pond Skipper View Post
Regarding tail feathers I have tried ply it can be thinner still a bit of foil shaping starting with a thicker piece.
The upshot is stiffer at higher speeds thinner and able to battle tumbles. I use longer tail moments to get
away with smaller tail surfaces. Always foil the surfaces to help the back end sit at speed.
I have tried a couple different ways to make the tail feathers today.
One was the usual 1/8" balsa sheet style, with the edges sanded to a fairly sharp edge. I am tempted to tissue and dope the wing and tail surfaces, then lightly paint the whole works with Klasskote. Just enough paint to be fuel proof but not pretty.

I have also laid up some carbon cloth tail feathers. The fin is 3 layers and from past experience will be .030" thick. The CF horizontal surfaces are pre-hinged with a strip of kevlar cloth as a continuous hinge. I pressed axle grease into the kevlar cloth where I do not want the epoxy resin to penetrate. So it is a sandwich of carbon cloth outer layers. I have my doubts how this will turn out, but at least it's a try. If it does work it will be nice and thin and of course fuel proof.
It might be a good idea to inspect this piece before the epoxy is totally cured so that I can make sure the hinge line isn't fouled with epoxy resin.

Last edited by combatpigg; 11-19-2020 at 04:06 PM.
Old 11-19-2020, 07:46 PM
  #47  
aspeed
 
aspeed's Avatar
 
Join Date: Jul 2011
Location: Ruthven, ON, CANADA
Posts: 3,396
Likes: 0
Received 3 Likes on 3 Posts
Default

The old speed planes were made of bass. Only a bit heavier than balsa and much stronger, and it flexes in a crash. After fibreglassing balsa the weight may be a wash.
Old 11-19-2020, 10:26 PM
  #48  
combatpigg
Senior Member
Thread Starter
My Feedback: (3)
 
combatpigg's Avatar
 
Join Date: Nov 2003
Location: arlington, WA
Posts: 20,016
Received 5 Likes on 5 Posts
Default

C/L Speedsters have to be tough..!
Old 11-27-2020, 03:40 PM
  #49  
combatpigg
Senior Member
Thread Starter
My Feedback: (3)
 
combatpigg's Avatar
 
Join Date: Nov 2003
Location: arlington, WA
Posts: 20,016
Received 5 Likes on 5 Posts
Default

Today was as nice as any November 27 is ever gunna be so I snuck out into a nearby hay field and got some video......
Old 11-28-2020, 06:32 AM
  #50  
Pond Skipper
 
Pond Skipper's Avatar
 
Join Date: Dec 2009
Location: Texas, TX
Posts: 2,794
Received 3 Likes on 3 Posts
Default

Awesome awesome great to see the design in the air Chuck!
Glide was easy on the ticker.

What a challenge the TD .051 becomes when max speed is the goal.
Easy enough with 38k performance engines or electrics.
The TD .051 can go very fast for those willing to go there.

Your at: vs / NX:
30 inch span / 24"
120 sq inch / 75"
11 oz RTF / 8oz
APC 4.2x4 prop / APC mod 4.3x5.5N down wind peak at cam: 28,746 rpm / 149.7 mph pitch speed / 143 mph doppler


Your Vid Stats:
In the hand 22,771
Passes near the cam: 25.45k to 26,162 rpm
Peak dive 27,697 rpm

I found through the process of designs / testing the closer you get to 1:1 the rpm can be milked / maintained in a slow
shallow 10 - 15 dive enough to hold rpm from declining too far before it gets in front of the cam / looking for rpm apex pass.
Found I could be at 85% thrust / weight ratio and maintain peak rpm in front of the camera but only with real steady locked in
passes no slip ups / corrections - straight slight angle down to keep the load low on the engine.

Thread Tools
Search this Thread

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

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.