HDTenEightyP/NetNews huggingface dataset:
From: petera@bcrka398.bnr.ca (Peter Ashwood-Smith 1600361)
Subject: Re: 2 stroke vs. 4 stroke engines
Reply-To: petera@bcrka398.bnr.ca (Peter Ashwood-Smith 1600361)
Organization: Bell-Northern Research, Ottawa, Canada
Date: Wed, 08 Apr 92 13:54:39 GMT

> Sean McCaskey writes:
>
>  Do you find the 4 strokes to be as easy to operate?  I have seen many 4
>strokes at our field (B.A.R.C.S. in San Pablo), but most of them seem to be a
>rail pain to operate.  I am not the best engine man my self, and I sometimes
>need a hand with the reliable OS 2 strokes.

  I own an OS120 4 stroke and have never had any trouble with it. It starts
almost always on the first turn and I never use an electric starter. I follow
the OS instruction manual and ignore most of the free advice from guys at
the field and have no problems. I did manage to strip the glow plug threads
once (ouch!) but sending the head to Clarence Lee Eng. with a check for 20$
set things right again (whew!).

  In general, the larger engines seem to be easier to start and run more
reliably than the smaller ones ... my impression anyway. I'm not sure how
good the smaller 4 strokes are? Anyone out there got say an OS 40 4 stroke?

   Peter.

Newsgroups: rec.models.rc
From: murray@csli.Stanford.EDU (Peter Murray)
Subject: Sailplane novice
Keywords: Sailplane, glider, Bon Jovi
Reply-To: murray@csli.stanford.edu
Organization: DSG, Stanford University
Distribution: WORLD
Date: Tue, 7 Apr 92 19:18:55 GMT


Hi NetModelers,

I am a novice to the sailplane realm, but eager to learn.  I have selected  
as my introductory platform the Goldberg Sophisticated Lady.  Any thoughts  
on that selection or experience with that craft?

I have three questions:

1)  I have a Futaba 6channel radio (FP-6FG) from the olden days.  Is this  
model still legal?  Will it be OK to use this with the non-mini servos in  
my craft?

2)  Should I get a tutor for my first couple of flights?  I have a bit of  
experience with fixed wing powered beasts, but no sailplane experience...

3)  Does anyone have a great book to recommend to the novice flyer?

Thanks!

Cheers,

Pete
murray@aslan.stanford.edu

PS:  I am an experienced model builder.  -pm
From: spenny@sw.stratus.com (Steve Pennypacker)
Newsgroups: rec.models.rc
Subject: Re: 2 stroke vs. 4 stroke engines
Date: 14 Apr 92 19:57:33 GMT
Distribution: usa
Organization: Stratus Computer, Inc.

In article <1992Apr13.081330.1929@inland.com>, bloom@inland.com writes:
> 
> Hmmmm, but a 2 cycle merely sounds like a Lawnboy lawnmower.  Do you know 
> of any full scale airplanes with 2 cycle engines?

Yes, I do actually.  All the Rotax engines except the new 900 series are two
cycles.  These engines are popular among homebuilders, and are used in designs
such as the Kitfox, Pulsar, and RANS series, to name a few.  They're also used in 
many, many ultralights.  IMHO, the difference in sound between a certified 
(4-stroke) aircraft engine and a Rotax is like the difference between an .049 and 
an R/C 4-stroke.


-- 
     Steve Pennypacker		     PP-ASEL

     spenny@wiley.ts.stratus.com     Stephen_Pennypacker@vos.stratus.com
Newsgroups: rec.models.rc
From: Iskandar Taib <ntaib@silver.ucs.indiana.edu>
Subject: Re: Controlling Glow Plugs (Ed Mosher, your mail bounced!)
Organization: Indiana University
Distribution: na
Date: Wed, 15 Apr 1992 19:21:32 -0500


Hi Ed... your mail bounced. 

I'd love to see your glow driver circuit. We'll have to arrange for snail
mail I guess..

-- 
-------------------------------------------------------------------------------
Iskandar Taib                          | The only thing worse than Peach ala
Internet: NTAIB@SILVER.UCS.INDIANA.EDU |    Frog is Frog ala Peach
Bitnet:   NTAIB@IUBACS                 !
-------------------------------------------------------------------------------
Newsgroups: rec.models.rc
From: Iskandar Taib <ntaib@silver.ucs.indiana.edu>
Subject: Re: Pulse Jet Engine
Organization: Indiana University
Date: Wed, 15 Apr 1992 19:51:45 -0500

In article <1992Apr13.082238.1930@inland.com> bloom@inland.com writes:
>In article <1992Apr9.173014.1694@vax1.mankato.msus.edu>, ultra10@vax1.mankato.msus.edu writes:
>> There is an add I see all the time in RCM for the plans to a pulse jet engine
>> you can build out of an aerosol can. JET ENGINE TECHNOLOGIES in Tx, sells the 
>> plans.
>> 
>> I am wondering if anyone has bought the plans and tried to make the engine ?
>> If so - Did it work? What kind of thrust did you get? Could you throttle down
>> to near zero thrust without the flame going out?
>> Is it easy to build ?
>> 
>> -Rob
>
>Any ad you see with a jet engine you can build is a scam.  There is no 
>such thing as a throttle on a pulse jet engine - it cannot work that 
>way.  An aerosol can?   Ho ho ho ho hee hee ha ha ha.  The other scam 
>is the turbine engine you can build from common household items. 
>Real (not to be confused with non working models) gas turbines require 
>high temperature heat resistant alloys, like nickel based superalloys. 
>Do you have any of this material stashed away in a kitchen drawer?

I don't see it as being too far fetched, but it won't be nearly as 
awesome as a Dynajet or something of the sort.

The pulse jets used in C/L Speed do have thin sheet metal bodies. 
The valve heads, though, are usually precision machined pieces of 
work. 

There was mention in the Scale R/C rag of a throttleable pulse 
jet engine someone wanted to put in a scale F4 or something of
the sort. As usual, the columnist was flaming AMA for not wanting
to have anything to do with it...those tubes get red hot when
running and a crash would start a fire at the very least. And 
talk about noise... fly a DynaJet at 3-400 feet and you'll lose
your flying site.

(I detest that magazine...)



-- 
-------------------------------------------------------------------------------
Iskandar Taib                          | The only thing worse than Peach ala
Internet: NTAIB@SILVER.UCS.INDIANA.EDU |    Frog is Frog ala Peach
Bitnet:   NTAIB@IUBACS                 !
-------------------------------------------------------------------------------
Newsgroups: rec.models.rc
From: mckiou@cbnewse.cb.att.com (kevin.w.mckiou)
Subject: Re: micro RC gear for SMALL gliders
Organization: AT&T
Distribution: usa
Date: Wed, 15 Apr 1992 17:38:00 GMT

In article <1992Apr15.123052.3359@unx.sas.com> snowem@echidna.unx.sas.com (Walter Edward Martin) writes:
>I need some facts/opinions. . . .
>
>I am considering building a small hand launched RC glider.
>The smallest radio I've seen so far is a Cannon 4-channel
>system with the following specs.:
>   
>     receiver             0.56 oz.
>     CE-9 servo           0.43 oz. ( X 2)
>     270 mah batt.        2.1  oz.
>     ----------------------------
>     TOTAL flight weight  3.52 oz.
>
>The system price (xmitter, Ni-Cads, chargers, etc.) is $244.95
>for a 2 servo system. 
>
>The following questions arise (especially since I haven't flown
>RC planes for 15 years):
>
>1) Is Cannon equipment good stuff? Any service problems etc.?
>

I have the micro-Cannon gear that I use regularly.  My recommendation
is NOT to use it UNLESS you absolutely are concerned about saving
every gram possible.  Under no circumstances do I recommned the Tx.
It is expensive and has annoyances like trim settings that are continuous
(that is, they do not click).  So you have to look at your Tx to determine
the proper trim setting (really bad news).

>2) Is there a lighter radio system?
>
No.

But you can get very close for alot less money.  For $169 you can buy
the Futaba Attack Sailplane radio which is configured like this:

	R114 Rx		.9 oz
	2 S133 servos	.6 oz each
	250 mah batt.	2.25 oz

I have used a Futaba Attack radio for the past year and am very happy
with it.  If you want to save another 1.2 oz buy and Airtronics 110 mah
Rx pack (~$17).  If you want extra servos by the $99 Attack and buy
the S133 servos (~$30 each) and Rx battery separate.

>3) Is this a good price? Where can I get this system cheaper?
>
As far as I know there is only one price on Cannon equip, retail.

>4) Are there any good RC/HLG kits available? Who stocks them
>   (mail order) and how much do they cost?

Chuperosa.  Northeast Sailplane Products (See RCM Magazine for address)
It's overpriced at $50, but it's about as good a kit as you will find.
Get the SD7037 polyhedral wing.

Kevin

---------------------------------------------------------------------
Kevin McKiou                         UUCP:     att!ih4sm!kwm
NAR 51581
AMA 380751
AT&T Bell Labs, Naperville, Ill      Internet: kwm@ih4sm.att.com
---------------------------------------------------------------------
Newsgroups: rec.models.rc,misc.forsale,na.forsale,ne.forsale,ny.forsale
From: spr@cunixb.cc.columbia.edu (Sebastian P Ruta)
Subject: Tamiya Porsche 959 R/C electric car 4 sale!
Reply-To: spr@cunixb.cc.columbia.edu (Sebastian P Ruta)
Organization: Columbia University
Date: Wed, 15 Apr 1992 02:38:54 GMT

I would like to sell the following:


1	Tamiya Porsche 959 with:
		-FAST!!! 4 wheel drive!!! On or off-road!!  
		-quality metal bearings
		-540 VRZ Technigold Motor
		

1	Leisure 107 AC/DC quickcharger
	
2	Futaba Attack 2NBR 2 channel radio 
	  	-(2-stick, reversable servos, BEC circuitry)
		-I have 2.  One is new, in box, except for the receiver
		   has been used (the servos and transmitter have never
	       	   been used.)

2	Futaba MC 112B MOSFET Electronic Speed Controller
		-With braking and reverse 

	Battery Pack (1200Mha, 7.2 Volts)


Best offers on all equipment. 

More details by email.  Bids by email only please.  I will respond to
serious offers...try me!


-- Sebastian 
   spr@cunixb.cc.columbia.edu
From: spenny@sw.stratus.com (Steve Pennypacker)
Newsgroups: rec.models.rc
Subject: Re: Slats v.s Flaps
Date: 15 Apr 92 13:45:05 GMT
Organization: Stratus Computer, Inc.

In article <1992Apr14.210454.16695@bmerh2.bnr.ca>, petera@bcrka398.bnr.ca (Peter Ashwood-Smith 1600361) writes:
> 
>    Has anybody given any thought to slats? I read a while
> back in rec.aviation that slats can contribute more than flaps
> to increasing a wing's lift. I've seen dozens of models
> with flaps/spoilers but never one with working slats, what gives?

Several years ago, there were either one or two articles on a plane called the 
Crane in Model Aviation.  It was a T-tail with lots of high-lift features like
slats and either slotted or Fowler flaps, and probably a high lift airfoil and
maybe STOL wingtips.  This was probably 7 or 8 years ago.  If you're really
interested, give AMA a call or check the Model Aviation plans listing for the 
exact date of the article(s).

Yes, slats are very effective in general.  


-- 
     Steve Pennypacker		     PP-ASEL

     spenny@wiley.ts.stratus.com     Stephen_Pennypacker@vos.stratus.com
From: miked@syscon.rn.com (Mike DeMetz)
Newsgroups: rec.models.rc
Subject: Re: R/C simulator for Mac!
Date: 15 Apr 92 13:03:41 GMT
Organization: Syscon International - Corporate Headquarters

Massimo Bigliardo <mb7r+@andrew.cmu.edu> writes:

>In my previous posting (April 13th), I really meant Flight simulators
>for Radio Controlled planes, developed or translated for Mac. I apologize,
>    ^^^^^^^^^^^^^^^^
>I thought it was clear, since this group is all about rc models.. BTW, if none
>postes a reply, I should conclude that you can't be a Mac user and a R/C modelerat the same time...

The Ambrosia Microcomputer AEROCHOPPER simulator is availible for the
mono MACS ie MAC II, Classic. It consists of a modified Futaba TX box
that plugs into the serial port. Does planes (glider,trainer,d/f and pattern)
and copters. Around $200.



?????????????????????????????????????????????????????????????????????????????
! Mike DeMetz                                          -----|-----          !
! Secretary-Michiana R/C Choppers                   *>=====[_]L)            !
!                                                         -'-`-             !
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
From: macs@worke.Eng.Sun.COM (This IS a test)
Newsgroups: rec.models.rc
Subject: Re: Takeoff Velocities of RC planes
Date: 6 Apr 92 23:11:16 GMT
Organization: Sun Microsystems, Mt. View, Ca.
NNTP-Posting-Host: worke

In article <92092.235003U54136@uicvm.uic.edu> U54136@uicvm.uic.edu writes:
>Out of curiosity, what are observed takeoff velocities of rc planes with
>about a 50" span and a weight of about 3-5 lbs. Guestimates are o.k. but
>no calculated values please.

Take-off speed is dependant on ...

	1) Relative wind speed

	2) Wing loading

	3) Airfoil type
	 
	4) ...


Well, I guess you get the picture.  I have two airplanes I fly regularly that
have very different rotation speeds.

One is 50" wingspan with a 9" chord.  The airfoil is semi-symmetrical and
the plane weighs about 3 1/2 lbs.  It is powered by a .19.  In a light
wind (~5 mph) it will take off at about 25-30 mph, ground speed.  In a 
strong wind (~15-20 mph) it will take off at about 15 mph, ground speed.
This seems to indicate that the airplane needs to be traveling at ~35 mph,
relative to the wind in order to take off.  I think I am wrong, but 
I think this means that this is the stall speed for the airplane.

On the other hand, I my Hammer 20 needs to be traveling at about ~45 mph
relative to the wind to rotate.  It has a 49.5" wingspan and has a tapered
symetrical airfoil from ~ 10.5" at the root to about 8" at the tips.
It weighs about 4 1/4 lbs.

I have seen Quickee 500s that have a 48" wingspan, weigh about 4 lbs, and
take off at around 90 mph, albeit after a very short take off roll :-)

In general, though, I think the average trainer (.25-.40) will take
off at about 30-40 mph. At least that is what all the trainers I
see at the field do.

By the way, has anyone out there built/flown a plane called the Bushwacker, 
originally kitted by Mark's Models, now with a Dynaflite sticker on it?
It's a .15-.19 powered ~64" span plane that has a long tapered wing
and is set up as a tail dragger.  It looks like it is pretty sleek,
but I can't help think of it as a small powered glider.  It looks like
it might be interesting though, it is 4-channel, and it seems that it 
would make a great knock around plane for low-level stuff. 

I'm thinking of getting one, but was wondering if anyone has had any 
experience with it.

Thanks.

Manuel.
Newsgroups: rec.models.rc
From: petera@bcrka398.bnr.ca (Peter Ashwood-Smith 1600361)
Subject: Re: Great Planes Super Sportster 90/120 review
Reply-To: petera@bcrka398.bnr.ca (Peter Ashwood-Smith 1600361)
Organization: Bell-Northern Research, Ottawa, Canada
Date: Tue, 07 Apr 92 20:49:12 GMT

> Larry Snyder writes:
>
>This plane is solid and takes abuse pretty well. Make sure the landing 
>gear mounts are well epoxied in. Mine came loose after a hard landing and 
>I had to cut into the wing to repair it. The landing gear wires also tend 
>to bend after hard landings.

I've just finished my second SS120 and agree with Larry about the gear.
I don't think they can take the normal punishment and as a result on my
first SS120 I rebuilt it with solid aluminum struts mounted in rubber pits. On
my seconds SS120 I have built solid aluminum struts with a T bar at the
top and two \/ gussets. They are mounted with nylon screws to a 1/4 pine
block in the wing. Not flexible but they will break away if the landing
is very bad. The alternative was to have the plane constantly wobbling
up and down on its wire legs with the wheel pants puncturing the covering.
I also use 3.5in wheels. One last mod I would suggest is to elongate the 
nose slightly since you will almost certainly be adding weight to the nose
to get the CG correct.

They are great flying planes though and nothing beats the look of an SS120
doing a vertical climb into a hammerhead followed by a 3 or 4 revolution
spin ....
It's what weekends were invented for :=)

I can also highly recommend the Great Planes Super Sport 40 although I would
think twice about using retracts unless you can make very smooth landings
consistenly. I used Dave Brown retracts initially but they only lasted
one summer then I replaced them with EZ retracts which have far less
moving parts.
Probably a good third plane though since they are land quite fast.

  Peter Ashwood-Smith
From: bloom@inland.com
Newsgroups: rec.models.rc
Subject: Re: Controlling Glow Plugs
Date: 14 Apr 92 14:25:45 GMT
Organization: Inland Steel Company; East Chicago, IN

In article <1992Apr13.012136.18406@sfu.ca>, larrie@beaufort.sfu.ca (Larrie Simon Carr) writes:
> In article <wdu8GCe00UzxM1dIhu@andrew.cmu.edu> mm7q+@andrew.cmu.edu (Michael Oliver Muller) writes:
>>
>>>I don't really understand your question.  You want to have a way 
>>>to control the current thru the plug element.  On my power panel, 
>>>about 3 amps gives a nice bright orange heat to the element.  The 
>>>only way I know how to alter the current in a fixed resistance 
>>>circuit (glow plug) is to alter the voltage that the plug sees.
>>
>>Two questions about this comment:
>>
>>1.     Does the resistance change as the glow plug heats up?
>>
>>2.     What is the resistance of a glow plug?
>>
> 
> The resistance does change and varies for different manufacturers
> and temperatures.  Typical values range between 0.4 ohms to about
> 0.9 ohms.
> 
> My brother has a old 12v to 1.5v power box which is a bunch of
> connectors and a 10 watt resistor.  However, the 1.5v depends
> on the glow plug used.  One set (dont know the manufacturer at
> the moment) were toasted as the applied voltage was around
> 2.2v.
> 
> I see in various RC magazines these power boxes with a adjustable
> control.  Do these boxes control the current or the voltage
> across the glow plug?
> 
> Maybe a better question is:  How are glow plugs rated, by a
> maximum current or a maximum voltage? 
> 
> As for help from mail: 2 votes say it is the current, 1 vote 
> says the voltage.

Here we go again!  The change in resistance of the glow plug 
element with temperature (while real) is of very little practical 
significance.  When you connect your glow driver to the plug, 
you increase the voltage applied to the plug gradually by turning 
up the knob on the panel.  This also increases the current through 
the plug.  The plug element will be around 1800F (bright orange heat) 
when you have the proper current or voltage (take your pick).  In this 
temperature range the resistance of the element is not going to change 
wildly as the engine starts to run.  Each manufacturer of plugs rates 
his plug by voltage (just read the label on the package, either 1.5V or 
2.2V for Fox plugs, dry cell vs wet cell battery type plugs).  If you 
don't want to buy or build a glow driver (variable voltage and current), 
just use a nicad or dry cell and the proper plug.  3 amps of current 
works just fine on all the plugs I have tried, and doesn't burn 'em out 
prematurely.  To test where your driver should be set, just take the 
plug out and adjust the current setting until you get a bright orange 
element.
From: ntaib@silver.ucs.indiana.edu (Iskandar Taib)
Newsgroups: rec.models.rc
Subject: Re: 2 stroke vs. 4 stroke engines
Date: 10 Apr 92 18:20:29 GMT
Distribution: usa
Organization: Indiana University

In article <1992Apr8.144724.18563@rtsg.mot.com> svoboda@rtsg.mot.com (David Svoboda) writes:
>In article <1992Apr2.174959.20657@pictel.com> santo@pictel.com (Santo Wiryaman) writes:
>|
>|4-stroke
>|--------
>| - Operates with larger prop at lower RPM which gives a pleasant
>|   (scale) putt..putt..putt sound.
>
>Or, in another opinion, has an unpleasant lawnmower sort of sound.  Not
>really scale sounding at all.

>Before anyone flames (in rec.models.rc?  Who am I kidding? :-), that is
>just my humble opinion.  Personal taste.  Unpopular personal taste.
>Downright *lonely* personal taste.


This brings up something I've been wondering about for
awhile. 

Last time I attended an airshow where some P-51s were 
flown I couldn't help but think.. hmmm those things sound
sorta like a muffled 2 stroke with a small prop.

The Mustang's prop produces a low note but the exhaust 
sound is quite high pitched, IMHO. 

If you think about it the Merlins do about 2-3,000 RPM
but there are 12 cylinders, so you multiply 3,000 RPM
by six and you get 18,000 exhaust pulses per minute. 

Wonder what a Lancaster sounds like...  8-)



-- 
-------------------------------------------------------------------------------
Iskandar Taib                          | The only thing worse than Peach ala
Internet: NTAIB@SILVER.UCS.INDIANA.EDU |    Frog is Frog ala Peach
Bitnet:   NTAIB@IUBACS                 !
-------------------------------------------------------------------------------
From: pl3x@vax5.cit.cornell.edu
Newsgroups: rec.models.rc
Subject: Futaba 4 Channel Sold! Thanx!
Date: 13 Apr 92 20:31:28 EDT
Distribution: rec
Organization: Cornell University

The Futaba 4 channel has been sold. Thank you for all the offers.

-Todd at Cornell, wasting eyes and mind ....
From: seanm@terapin.com (Sean McCaskey)
Newsgroups: rec.models.rc
Subject: Re: Futaba 4 Channel RC radio for sale
Date: 24 Mar 92 14:23:06 PST
Organization: Not an Organization

  About your radio:

  It is probably not usable at a AMA field as it is not a "91" narrow band
transmitter, though it can probably be upgraded to such for about $85 bucks. 
What happens when you do that is a tech checks over your TX and makes narrow
band modifications and they sell you a new RX for the radio.... Usually a
painless operation and it can sometimes be done while you wait.

  I am interested in your sailplane pieces... Mostly am looking for Oly II and
Segita parts (wings/fuse etc)

  Please reply to seanm@terapin.com

---Sean---
Newsgroups: rec.models.rc
From: mkfeil@bcrki9.bnr.ca ()
Subject: Re:    Electric Glider H/W
Organization: Bell-Northern Research
Distribution: na
Date: Thu, 16 Apr 92 15:39:59 GMT

In article <92106.120855ACAD8061@RyeVm.Ryerson.Ca> Farago, Anthony <ACAD8061@RyeVm.Ryerson.Ca> writes:
>From my relatively inexperienced point of view these things
>seam like a hot setup since they would give you on/off control
>of throttle without a servo and eliminate the rx battery pack.

You are right. It is definitely the way to go, in my opinion.

>But the question is once the Auto-Cut-Off has disabled the motor
>how much time can you expect from the battery for running the
>receiver and servos used for elevator, rudder and perhaps ailerons,
>flaps and spoilers?  It would not be very impressive if you got
>an excellent climb just to lose control after 5min of soaring.

I have definitely not found this to be a problem. There is a considerable
reserve time, especially if your cells are not perfectly matched. I would get
worried only after 15-20 minutes. To be safe, I will almost always shut down
the motor before the auto cutoff triggers. This is the beauty of on-off
control.

Often I find good lift after only a minute or two of battery run, and can
soar with confidence, knowing that I have literally hours of time. If I hear
that my motor is running low, I will not let it die if I think I can stay up
a while without it.

On rare occasions, I have let the auto-cutoff trigger and set up for a
landing, only to find booming lift. A great opportunity for a 15-minute bonus
ride!

Go for it!
Max
--
Max Feil                 
Bell-Northern Research    Internet: mkfeil@bnr.ca
P.O Box 3511 Station C,
Ottawa, Ontario, Canada.  - What do I know? I'm just a Nerd on the Big Ranch. -
Newsgroups: rec.models.rc