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General control line discussion => Open Forum => Topic started by: Chuck Matheny on September 14, 2020, 05:21:45 PM

Title: Ever Built Dick Mathis' Piper Cherokee...?
Post by: Chuck Matheny on September 14, 2020, 05:21:45 PM
This was my first BIG plane, after learning how to fly with Goldberg 1/2A models. With an urge to move on to "bigger and better" stuff, I bought the book "How To Fly U-Control", by Dick Mathis in 1985. Inside the book is a semi-scale drawing of a 36 inch span Piper Cherokee complete with construction details. OK, now I needed to buy a pile of wood and get to work..!
I used a McCoy .35 to power it, and built it with flaps [!]. I flew it with either 60 foot or 70 foot lines depending on how well the McCoy was running that day.
Without knowing any better, I was thrilled with how well it performed.
Eventually it became so fuel soaked that it was given the Viking funeral.
I am curious to hear about who else built this model.
I would like to build another one for purely nostalgic reasons.
Title: Re: Ever Built Dick Mathis' Piper Cherokee...?
Post by: Steve Helmick on September 14, 2020, 05:33:03 PM
No, but great to see you here on Stunthangar, Chuck! A Dick Mathis "Excalibur" was my first .35 sized stunter, and I also want to do a repeat...OS .35S power....again. Two other club members built them, one Fox .35 Stunt, McCoy .40 and my OS. I flew all of them, and liked the McCoy powered one best. Mine was tailheavy, with the OS (no muffler).  It'd be great to see you out flying. Leidle is probably active flier closest to you.   H^^ Steve
Title: Re: Ever Built Dick Mathis' Piper Cherokee...?
Post by: John Leidle on September 14, 2020, 06:21:02 PM
  Steve,    Leidle hasn't been active since they dug up his flying site,,, however he will be active soon with a new place awarded to him by the  folks at the Arlington airport.   I was given orders to approach anyone flying anything other than Tether lined models .... I was given this site because I'm a careful , cautious person ... I don't care to loose this one .
     Chuck , glad you are talking to us   I'll be up your way at the airport Wednesday I think ... I plan to mark out my circle... cut it after it rains  don't want to have anyone worry about me starting a  fire with my non electric mower.
             Hope to see you soon ,  John L.
Title: Re: Ever Built Dick Mathis' Piper Cherokee...?
Post by: Chuck Matheny on September 14, 2020, 07:23:58 PM
Steve and John..very nice to hear from both of you..!
I got the itch early this summer to get back into C/L and of course as soon as I was ready to head down to the airport to fly C/L for the first time in 14 years, that's when I saw the field all torn up with heavy equipment.
It never fails.. ::)!!
Rob Putnam was the airport manager at the time...almost 20 years ago who I approached to get permission to fly there. At that time he warned me that the area next to 172nd street was "due any day now to be turned into more airplane hangars". He was quick to say that the flying circles could be moved elsewhere on airport property. What a nice guy..I was mildly surprised to find a public servant willing to take us on..that is of course after I signed a "Hold Harmless Agreement" that would prevent ALL FUTURE AMA C/L FLIERS from being able to sue the City of Arlington for any negligence..
Steve, I'm happy to hear you liked the Excaliber / McCoy combo, I will give that one a look. I need to find a rod for my McCoy .35..but don't we all..?
john..I think you might "officially" be the last guy I saw flying at Arlington before the bulldozers arrived. My 100 acre RC flying site [it actually belonged to a Korean War pilot] right off of Smokey point Blvd was taken away a couple years ago. In it's place up went what they call it a "Behavioral Needs Hospital" or something like that. Isn't that what this hobby is all about...Behavioral Needs?
Title: Re: Ever Built Dick Mathis' Piper Cherokee...?
Post by: John Leidle on September 14, 2020, 07:35:46 PM
   Chuck,
  We can fly together we have their blessing. Safety will keep us there for a good while. Rob Putman told me " I hope the gravel road that is coming doesn't get in your way John , if it does I'll try to get them to shift it for you" that is the current road. A class act he was,  I  told my wife this morning " if we don't use the City operated Golf Courses some Zero on the City Council will turn them into a Methadone facility or flophouse for misfits or people that don't  belong here so use them... your story is what I'm talking about.   
  If you need some glue, a prop or fuel to try let me know I have a bunch of stuff. We got along when we worked together I think we can get along flying together.   Let's go flying Chuck,,,
      John L.
Title: Re: Ever Built Dick Mathis' Piper Cherokee...?
Post by: Chuck Matheny on September 14, 2020, 08:38:59 PM
 John, the weather has been absolutely perfect lately without the sun.....! Yep, it was quite the coincidence that a couple of Airplane Nut IBEW Electricians met at the Fred Hutch Cancer Research project so many years ago. That was "stoop labor" all day, every day with not enough room to fully stand erect in many places in that Mechanical mezzanine.
Of course a Neanderthal like you wasn't inconvenienced too badly by that.... LL~
Title: Re: Ever Built Dick Mathis' Piper Cherokee...?
Post by: John Leidle on September 14, 2020, 11:17:27 PM
  Chuck,
  Working for McBride in the interstitial was a challenge I walked around on all 4s for maybe 5 months... I had 2 guys come in & see me & saying " look there is a guy walking around on his hands & knees" then they walked off the job,
   Was on worse jobs,,,
           John L.
Title: Re: Ever Built Dick Mathis' Piper Cherokee...?
Post by: Chuck Matheny on September 15, 2020, 12:00:33 AM
There were so many bad jobs that it's hard to choose the worst.
Where do you buy stuff like double flared eyelets, bulk flying lines, line crimps, tin fuel tanks, balsa, locking collet NVAs...straight nitro...etc....?

Sig is out of almost everything.
Sig claims that there has been a huge influx of building going on this past year.
I hope that is true.
 Tower Hobbies has an average wait time of a 1/2 hour with real @#$% poor help on the phone. A 180 from the way I remember them.
This is kinda what my Dad warned me what living in Russia would be like... :-\
Title: Re: Ever Built Dick Mathis' Piper Cherokee...?
Post by: Perry Rose on September 15, 2020, 05:09:46 AM
Check Brodak.com and MBS for lines, plus the vendors corner at the bottom of the pages.
Title: Re: Ever Built Dick Mathis' Piper Cherokee...?
Post by: John Leidle on September 15, 2020, 10:53:39 AM
   I have an idea you can get nitro on ebay from Torco. I have used lots of Torco mix in the last several years. Balsa may be available on this site . Bulk lines on this site & search the web.
         John L.
Title: Re: Ever Built Dick Mathis' Piper Cherokee...?
Post by: Chuck Matheny on September 15, 2020, 06:52:43 PM
Thanks John. Torco has 5 gallons of nitro for $300  plus shipping. Otherwise their 1 gallon price was about $80 + sh. I can make 10% nitro fuel work for just about everything, so that's getting by relatively cheap...this means I can brew my own 25% oil, 10% nitro fuel for less than $15 per gallon.
Here is a little progress with the Cherokee. Mathis doesn't use a solid TE with his design, he just sheets both sides of the ribs at the TE with 1/16" balsa. This works..but leaves very little meat for flap hinges. So I deviated from purist Nostalgia Stunt  and used a solid TE. the flap joiner is 5/32" alum Tig  welding wire with a 3/16" alum tubing bearing. The U shaped wire is filed flat so it sits flush in the 1/8" thick flaps.
The wing ends up being 36" x 10".
Mathis specified a .19 to .35 engine back in 1974.
I've got a ST.35 stunt engine [225 g, no muffler with freakishly small 3/16" venturi]..or a Fox .35 bypass with a 4 hole backplate [198 g, no muffler] and a McCoy .35 [209 g, no muffler] ..
Other choices are a OS .32 SX [246 g, no muffler].... OS .15 CVA [190 g with muffler].
I'd like to aim for adequate power but not overkill on 60 foot lines. The OS .15 CVA is an unknown commodity for me, since I've only used it for RC projects. I think it'll turn a 7 x 5 well enough on a C/L plane this size for 80 mph..but using it with 60 foot lines with a 20 oz plane might be too much to ask..?.
Title: Re: Ever Built Dick Mathis' Piper Cherokee...?
Post by: John Leidle on September 15, 2020, 07:50:38 PM
  Looks promising.
  John L.
Title: Re: Ever Built Dick Mathis' Piper Cherokee...?
Post by: john e. holliday on September 16, 2020, 12:34:49 PM
I myself have quit using nylon hinges.  Using cloth hinges full length of flaps. D>K
Title: Re: Ever Built Dick Mathis' Piper Cherokee...?
Post by: Steve Berry on September 16, 2020, 12:45:44 PM
Everybody, remain calm and you will make it through this. This is a (short) hijacking!

I myself have quit using nylon hinges.  Using cloth hinges full length of flaps. D>K

Just curious what you use for attaching the hinges? Dope? Ambroid? Polycrylic?

Ok, hijacking over. See? You survived.
Title: Re: Ever Built Dick Mathis' Piper Cherokee...?
Post by: john e. holliday on September 16, 2020, 12:54:02 PM
I now use sig glue.   Used to use dope clear butyrate, but no more.  Material is sig Coverall cut in 3/4 inch wide strips. D>K   
Title: Re: Ever Built Dick Mathis' Piper Cherokee...?
Post by: Steve Berry on September 16, 2020, 01:06:41 PM
Sig-ment, Sig Bond, or Sig Super Weld?

I've used aliphatic glues and ambroid/sig-ment, but have never really been satisfied with the results. Was hoping to try dope or maybe even something like Polycrylic to attach them.
Title: Re: Ever Built Dick Mathis' Piper Cherokee...?
Post by: L0U CRANE on September 16, 2020, 02:25:12 PM
Very enjoyable discussion! Thanks!

I believe the high wing Cherokee was kitted by M&P, as was a low wing (named?) otherwise identical. The third one was (again) the same design but with twin fins - egad! - an Ercoupe!

Built one in the 1970's for a Silver Swallow (Chinese) .15 diesel, MUCH fun flying it. Great fun airplane, even if one fin, or the other, or both seldom came home still ON the model.

Still have it, with the same engine. too. Kinda shudder at the thought of piling modern, or even vintage, horsepower onto it. That little .15 was plenty. Didn't seem to care whether the lines were 52.5' (then thought mandatory for .15s) or something around 57.5' or 60'.

Hope you enjoy the heck out of it !
Title: Re: Ever Built Dick Mathis' Piper Cherokee...?
Post by: Rick Campbell on September 16, 2020, 03:02:12 PM
I did build one when I was a kid . . . that was a LONG time ago. M&P kit. I think I had an Enya .29 on it.  Because of the high wing, it did sit cockeyed on the lines, but it looked pretty cool and I learned a few stunts with it. I taught myself the pattern using Dick's "How to Fly U Control" book. Good times.
Title: Re: Ever Built Dick Mathis' Piper Cherokee...?
Post by: James Lee on September 16, 2020, 03:11:47 PM
Well, I will hijack this again.  but, I think I have that M&P Ercoupe kit stuffed away somewhere...
Cloth hinges  - I use wedding dress lining, yes, that is what the fabric store says it is.  .003" thick ...    three to five coats of dope on the bare wood.  cut the material in 1" to 2" wide strips and attach with Very Very thin dope.  Mostly thinner.  Do the stab first or elev and let it set a bit before doing the rest.   Then continue with theh clear dope for the base of the finish.  the hinges become part of the finish.  With a bit of work ,they will disappear... 
Jim
Title: Re: Ever Built Dick Mathis' Piper Cherokee...?
Post by: Trostle on September 16, 2020, 06:55:25 PM

I believe the high wing Cherokee was kitted by M&P, as was a low wing (named?) otherwise identical. The third one was (again) the same design but with twin fins - egad! - an Ercoupe!

(Clip)


I am not trying to hijack this thread.  However, I do not know what a" high wing Cherokee" would be.  The Mathis Ercoupe was published in the June 74 issue of Flying Models.  Low wing with noticeable dihedral.  Dick Mathis did a profile high wing semi scale of the Citabria, Flying Models, April 73.  Even with the high wing, it had dihedral - 1/2" under each tip.  In the article, Mathis said it flew "just fine".  (This one is on my bucket list.)  Maybe this is the "high wing" design mentioned in the above post.

One thing about all of Dick Mathis' designs, both for control line and free flight - they all were practically designed and they all flew well.

Keith
Title: Re: Ever Built Dick Mathis' Piper Cherokee...?
Post by: Mike Griffin on September 16, 2020, 09:29:26 PM
I produced a kit of Dick's Cherokee years ago when I first started producing kits.  I think I sold maybe two.

Mike
Title: Re: Ever Built Dick Mathis' Piper Cherokee...?
Post by: Gary Mondry on September 16, 2020, 09:36:28 PM
As I recall, the M & P kit line-up included the Cherokee, the high winged Cardinal, and I think a V tail Bonanza.  They all were of otherwise similar layout with constant chord wings.

I just looked at Bob Mears’ controllineplans.com website and found all three under Aerosport.  Was that the same as M & P?
Title: Re: Ever Built Dick Mathis' Piper Cherokee...?
Post by: richardhfcl on September 17, 2020, 07:54:12 AM
Didn't M & P also market the Mongoose I?  It was very popular in Davenport. IA, for slow combat.
Title: Re: Ever Built Dick Mathis' Piper Cherokee...?
Post by: dave siegler on September 17, 2020, 12:48:30 PM
plans here,

https://outerzone.co.uk/plan_details.asp?ID=9174 (https://outerzone.co.uk/plan_details.asp?ID=9174)