Thursday, March 23, 2017

Polecat X – P30 Build Report

This is my second P30 rubber free flight model, the first being the NJAPF design by Al Lidberg. My first P30 sat in my basement a long time before test flights and then last year I installed the DT system and flew it in contests.  For my skill level it did well and at the last contest I thought I might never see it again because it was circling ever higher far downwind.  It did come down and Gary Oakins found it, but with a stab DT I worry if another time it might be miles away. 

Polecat X P30

NJAPF First P30

Don DeLoach was running a special if you ordered multiple plans there was a discount so I ordered the Pearl e202 E36 and Polecat X plans with short kits.  I flew the Pearl E36 a good deal last year and learned much about e36, this year I wanted to get the Polecat X flying.  There was so much different about the constructions of the Polecat X than the NJAPF so I asked a lot of questions online. First I had to order carbon strips that reinforce the wing, ¼ mil Mylar covering, and picked up Balsarite at local hobby shop to stick the Mylar down. Wing and stab construction went well but then I built my first round tube fuselage by wrapping balsa around a pipe, that went alright too. Covering with the Mylar went better than I thought it might, some Design Master spray paint gives it some color. 

Wing Before Carbon Strips

Stab With Carbon Strips

As I completed each major structure I weighed it and then again after covering to compare with the suggested weights on the plan, my weights were close but slightly higher. This is really a detailed plan which I appreciate; no other instructions are really needed.  The contest wins for this model are really impressive and it is a plane that has been refined over many years of contest flying. With the rearhook is in the very back of the fuselage and with a light airframe a really long rubber motor can be used to get a slower climbing motor run that lasts a long time.  It is my understanding it could be possible to get a 2 minute max with the rubber still turning the propeller.

DT Only might not be available
Another new item I wanted to try was the BSD Micro electronic “DT Only”. The weight without battery should only be around 1.5 grams, the battery is a single cell lipo as small as 35 mah.  After trying some ideas of mine that did not work for the DT parts on the plane, I used the method shown on the plan when using a viscous DT timer.  The tiny servo built into the electronic unit does not have a lot of force so having the proper linkage is essential. Adjustment for DT time is done with a really tiny potentiometer that is rather fragile.  When you have it set correctly the DT time should be completely consistent in all conditions. This is the first time I am using the pop off wing idea in the DT which is said to be the only sure way to bring a P30 down from a strong thermal. 

Gizmo Geezer on Test Stand

Again I am using the Gizmo Geezer propeller system, I had installed this on my NJAPF p30 the end of last season and it worked well. With the Gizmo Geezer a certain amount of tension is held in the rubber so braiding is not needed and it has a good working freewheeling system. A couple of people had a concern with all the downthrust called for on the plan if the rear of the Gizmo Geezer might touch the top of the fuselage, I still need to test this.

Now if the weather would cooperate, I could try some test flights.

Update 3/29/2017 - I tried test flights on 150 turns, flies well.

Polecat X 150 hand winds

Bill Kuhl

Related Links  Pearl Free Flight website
Gizmo Geezer Propellers  DT Only timer does not appear to be on the website any longer.  Gizmo Geezer Review Part #1  Flying With the Gizmo Geezer

Tuesday, March 21, 2017

Radio Control Years – Tales of an Ancient Modeler

As promised I am continuing my book report of the Norm Rosenstock autobiography when Norm starts flying radio control. In this time period the modeler pretty much built most of the radio equipment themselves. Both transmitter and receiver were vacuum tube technology which required lots of batteries to supply the vacuum tubes which employed a heating element inside. The equipment was not proportional, that is a control surface moved when a button was pushed but even more difficult was to turn opposite direction two button pushes were needed and you had to remember what control you gave last.  Power to move the control surface was twisted rubber driving an “escapement”. Only one plane at a time could fly because the radio equipment was not very selective.

Good Brothers Guff at AMA Museum

Guff Radio

Another AMA Museum Plane
Museum Radios

I have never flown an escapement single channel airplane but have flown a couple types of single channel systems, one was pulse proportional and the other was a fairly modern toy-type airplane, Micro Flyer that used two push buttons for rudder and speed control by push buttons. Pulse proportional did move in sync with the control stick but the actuator connected to the rudder was continuously moving from one direction to the other. Control was done by moving more in a direction while pulsing back and forth.  It is amazing how well you can fly with rudder only control with some practice and proper airplane trim.  With the Mattel pulse proportional radio I flew a Littliest Stick powered by a Cox .020 and even did loops.

My Mattel Pulse Proportional Radio

My first equipment was “reeds” equipment which is mentioned in the book.  Reeds equipment was not proportional and you could only give one command at a time but multiple control functions were available. The equipment was obsolete at the time but I was happy to start flying RC at 13 years old, not too long after that I had a World Engines Blue Max proportional radio. I did have one plane flyaway with the reeds equipment but it was found by a farmer who returned it, I have another blog post telling the story.

My Reeds System Transmitter

Reeds Receiver

Reeds Receiver

People are so spoiled today with the modern radio equipment that comes ready to use and so reliable. There can be something to be said for being forced to innovate. Norm found solutions for smaller transmitter antenna, not needing all the expensive batteries in the transmitter; he built his own receivers, and had very stable airplanes that flew with only rudder control.  The only thing I can relate to this was when my flying buddies and I first started flying electric RC indoors; the equipment was so basic at first but advanced amazingly fast.  This spirit of innovation is what has really made this country great but we tend to not appreciate all the advances sometimes. My father was pioneering in the design of farm machinery in the same time period that advances were being made in radio control.  

My First Proportional Radio

In one of the chapters in the book, Norm teams up with Bill Winter, everyone has heard of Bill no doubt; they are trying to set a RC duration record.  The airplane which is basically a free flight with rudder control powered with .09 diesel. As it is using an escapement powered by twisted rubber they want to use as few turns of the rubber as possible by using the rudder control as little as possible. So using multiple transmitters they fly upwind with first transmitter and pilot upwind takes control as the other transmitter is shut off, actually they were going to try with three transmitters. The furthest upwind pilot puts the plane in a gentle turn so it can circle downwind in free flight mode until it is over the downwind pilot, the process was repeated.

Details About the book: Tales of an Ancient Modeler
Paperback: 179 pages Publisher: N. Rosenstock; First edition (August 25, 1989)
Language: English ISBN-10: 093457510X ISBN-13: 978-0934575102

National Model Airplane Museum - Muncie Indiana

From the AMA Model Aviation Hall of Fame Check Out these Biographies Mentioned in the Book  Norman Rosenstock    Joe Raspante  Larry Davidson  Bill Winter

Related Video  Good Brothers Pioneers in Radio Controlled Model Aviation 
Very interesting video from the AMA  Flying Single Channel Escapement RC  Flying Single Channel with a superregen rx and escapement My Video Clip about the Micro Flyer

Related Blog Articles 
First part of the book about free flight. 

Bill Kuhl

Tuesday, March 14, 2017

Norm Rosenstock – Tales of an Ancient Modeler

History is more interesting to me as I get older; studying it I believe gives one a better appreciation of what others have contributed in the past and a better understanding of what the future could hold. For a few years I was creating documentary videos of local history. One of the videos was about the local full-scale aviation hero Max Conrad. The interest in Max started after reading the Book into the Wind the biography of Max Conrad.

Another Interesting Book 

More recently I have been more active in outdoor free flight competition and was a contestant last summer in the Outdoor Free Flight Nationals in Muncie Indiana. Along with a huge number of types of free flight models were the old time models both rubber powered and gasoline engine powered. For the first time I did a tour of the National Model Aviation Museum on the site, it was the closest thing to time travelling to be able to see the many older and famous models.

National Model Aviation Museum Muncie Indiana
Norm was cutting parts for this kit at one of his jobs

Carl Goldberg Valkyrie in Museum 
1950's Hobby Shop Recreated at Museum

After losing my first Tales of an Ancient Modeler book I recently ordered a used one in good shape for a reasonable price. Norman Rosenstock begins his modeling story in 1932 when he built his first model airplane at the age of eight, probably about when I started also. When Norm was 14 he got his first gas engine a Brown Jr. which cost $10, a lot of money during the Depression. To fly the large gas engine powered free flight models he designed and built, Norman and his friends would make the one hour subway ride to Van Courtland Park in the Bronx New York.  It was interesting to me that another famous modeler Frank Zaic was also riding the subway to Van Courtland Park to fly a few years earlier. 

Oldtimer Flying Muncie 2016

What I take away from reading this book is the hardship the young people of this time period endured to fly the model airplanes they built with inferior materials and tools. Norm tells of an incident where he wanted a new engine really bad and skipped lunch for weeks to pay it off. Before 1941 free flight models did not have dethermalizers to bring the plane down, so no doubt many models were lost.  It is interesting also how many famous modelers did come from the New York area such as Sal Taibi,  Joe Raspante, Larry Davidson, and more.  Larry has emailed me about his friendship with Norm.

Larry Davidson photo Lanzo Bomber

Larry Davidson photo Brown engine

I am going to end this blog report with a bunch of sources to check out further and a list of vendors selling materials related to older model aircraft. In the second half of the book Norm describes his adventures into radio control models, I will write another blog post on that. Some of the video links are of 1930’s subways, ignition model engines running, and old model planes flying but not in New York. Another book that relates to the history of model aviation is Do You Speak Model Airplane by Dave Thornburg, I plan to read that book again

Bill Kuhl

Update Norm is mentioned in this article on the Mite 098 Diesel.  

Tales of an Ancient Modeler by Norman Rosenstock 
Paperback: 179 pages Publisher: N. Rosenstock; First edition (August 25, 1989)
Language: English ISBN-10: 093457510X ISBN-13: 978-0934575102

Do You Speak Model Airplane  by Dave Thornburg
Publisher: Pony X Press (January 1, 1992)  ASIN: B002ANRY8G

Phd Dissertation on Model Aviation in the past almost 400 pages

Really interesting reading from AMA website
AMA Model Aviation Hall of Fame “Established in 1969, the Hall of Fame honors men and women who have made significant contributions to the sport of aeromodeling. Contributions may be in volunteer or administrative activities, product development, competition performance, or a variety or combination of activities.”

National Model Aviation Museum

Ask Claire from Nation Model Aviation Museum – I have been watching the live broadcasts through Facebook

Vendors of Related to Older Free Flight Model Airplanes
Larry Davidson - - ignition engine parts
Texas Timers – – timers for ignition engines
Jim O’Reilly Plans -  plans and short kits
BMJR Models -   kits  Old Time Rubber models and propellers   plans  kits  Bob Holman Plans and short kits  Free Flight Supplies Mike Woodhouse UK  plans National Free Flight Society  Balloon Wheels
Aero Dyne  - plan website is in process of being transferred. Outerzone free plans to download
 Hip Pocket Aeronautics Builder’s Plan Gallery free plans to download must be a member 
SAM - The Society of Antique Modelers   find additional vendors on the website and a wealth of information.  

Just Added - Belair Vintage Kits  Norm Rosenstock appears in group photo.

Video Links   Borough Hall subway in the 1930s - Brooklyn, New York   Mighty Atom model airplane engine 1934   Pioneers of Model Aviation - Carl Goldberg   Newsreel of 1936 Model Airplanes Championship, Brown Jr. Engine    Brown Jr airplane engine running  1939 model flying Dublin Ireland

Tuesday, March 7, 2017

Bad Axe Embryo – Thermals Do Not Care

I am less than pleased with myself in the construction and covering job on the Bad Axe embryo class rubber free flight from Volare Products. In no way can I blame the short kit or the plans, some of the problems I believe is in wood I selected for stringers in constructing this model. The Bad Axe embryo won the Embryo Event at the 2016 Outdoor Nationals Free Flight Contest in Muncie Indiana for George Bredehoft.  I was at that contest and met George in person for the first time. I took a picture of his Bad Axe while he was winding but somehow missed the flight. 

Bad Axe Embryo

Thermals do not care what an airplane looks like is what a couple of people told me when I mentioned my less than stellar covering job. Now I have built small rubber models before and did a pretty good job including two embryo models, the Peck Prairie Bird and the Volare Sky Rocket and the covering went on fairly well. These were full kits that included all wood. Another similar sized model I built was a Herr Champ that unfortunately included stringer wood that was too heavy, the covering went on fine but the model barely flew.

Picture Does Not Really Show Bad Fuselage

When I thought about building the Bad Axe I wanted to keep it light so I ordered some really light 1/16” square stock. When I built the fuselage the outside stringers just did not bend evenly and by the time it was constructed it had this wavy look to it if you looked closely down the sides. Various times the stringers would break on me so I doubled the 1/16” stringers in the front of the fuselage.  In doing some research I found some other people had trouble with the pre-cut 1/16” balsa. Bob Clements gave me a suggestion of a business that sold some good pre-cut balsa,  Hobby Specialties I will have to check them out in the future.

George's Nats Winning Bad Axe

Covering the Bad Axe I started with the tail surfaces, I was afraid the stabilizer would warp so I covered that rather loose and kept it pinned down while spraying on clear Krylon.  To adhere the tissue I used the UHU gluestick for the first time which many modelers use. It is not available locally so I ordered it through Amazon and it took a month to come from Thailand. Then I found out George sells it through Volare. This gluestick seemed to apply smoother than some other brands I have tried. The wing I did water shrink but pinned it down. It came out fairly well using some heat while shrinking.  I tried mixing rubbing alcohol with water for the shrinking  which should slow down the shrinking process. The fuselage I could not really get in a jig and this gave me fits, several places I cut out sections of tissue where it wrinkled and tried again but still not much better.

Could not get Wrinkles Out

Even though the fuselage has some uneven bends in it I think it ends up fairly straight back at the tail surfaces.  I added a fuse DT system with the front of the wing raising up. On my Guillow’s Lancer I had this type of DT and it appears to work pretty well. 

It has been extremely windy recently but I hope to get a chance to fly the Bad Axe on the first calm day. Included below is an extensive listing of resources including articles on covering with tissue.

Update 3-9-2017

I made some short test flights with less than 100 turns, flight pattern appears to be fairly close.

Bill Kuhl

Vendor Links                      Bad Axe Embryo on Volare website   About George Bredehoft designer Volare Products  UHU Gluestick   Hobby Specialties

Articles on Covering with Tissue

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