subarubrat

My Feedback: (1)

I finally got my hands on two mint Cox Cessna 182s from back in the day and one is getting turned into what I always wanted. This is the plane that I looked at in the sears and cox catalogs for most of my childhood and asked for it every Xmass but somehow never got.

I would like a few opinions on my plans. My goal is to keep the weight about stock or drop it slightly but add as much functionality as possible. I had thought of going strictly old school and using the Sanwa radio and the QRC but I like the idea of maximum functionality. I like the experience with Norvel I have had on my LMH 110 but I want to stay Cox. So I plan to use modern micro gear and a TD .051 with throttled carb. The TD puts out allot more power than the QRC as I recall and would allow the use of a larger tank. My school yard field doesn't have the largest usable takeoff area so I want to maximize a short takeoff roll. So if you would review and give me your opinion:

Replace stock QRC with throttled TD051, throttle by GWS pico

elev,rudder,nosewheel by Hitec HS55

Add flaps using HS55

GWS 6ch RX with a 250Mah RX batt

This puts me at: RX .29oz
3 HS55s .84oz
1 pico .22oz
flight pack 1.2oz
TOTAL 2.55oz

plus .44oz for aileron servos.....

The stock gear weighs in at about 8oz total so I am coming out 5 oz lighter with more power.

My biggest question is what prop to use, I used to use 6x3s and such on my 1/2a warbirds but this needs a nice high volume low speed thrust. So what prop will the TD swing that is best for this? 7x3 ?

And, I can clearly spare the extra .44oz to put in aileron servos and have rud,ail,elev,throt, and flaps. I think this would be ideal to show a full function 1/2a. About the only trick I would really like to add is brakes.

Do you think I will get decent STOL with this plane given the 5oz weight reduction and increase in power?

flyinrog

My Feedback: (1)

It appears you have clearly done your own homework on this.. a 5 channel 1/2a!! I have 2 of the cox Fairchild 24 planes that I fell for a few years back and am thinking of a Norvel change for one of them,,but flaps and brakes..yikes...cant help with prop choice but your at the right place for it....Rog....DB?..CP?..TW.?...Deadstick?..BM?..AJ? ..BobHH?

BMatthews

Yes it will. But the TeeDee likes to rev and won't put out the power if you lug it down with a larger prop. Stick with a 6x3. For takeoff use about 15 to 20 degrees of flap. More adds more drag than lift.

Sounds like a nice upgrade plan to me. But the TeeDee is going to make this model perform more like a Bearcat than a Cessna.

subarubrat

My Feedback: (1)

That was my though when I considered the 6x3, it made my bearcat fly like a bearcat. I never used a larger prop and given that lack of experience and no recent cox experience in the last 15 years I am searching for advice. Is there a better engine choice for this project? Modifications to the TD, lower compression head to reduce RPMS or some such change? Cox texaco head or something? Or would it be more reasonable to use the excess thrust for takeoffs and aerobatics and just using partial throttle as the norm?

combatpigg

My Feedback: (3)

If you're looking for chuggin' power, put a diesel head on a BIG MIG or AP .061. This will give 13,000 with a 7x3 APC.

subarubrat

My Feedback: (1)

I really like Norvel but I am wanting to keep this Cox powered if at all possible. I did consider converting it to diesel but then I remembered the hours of hell trying to get my davis diesel conversion running back in the 80's. Are they still as bad as thy were then with the contra pistons and teflon disks and such or is their a working diesel conversion out for the TD?

combatpigg

My Feedback: (3)

The DAVIS heads suck, I think the ones I have are from RJL. I have had good performance from diesel, but I have also snapped a couple of rods. Maybe the best way to go is with a PAW .049?

Richard Say

Subarubrat,
Rather than 'detune' a Cox TD, I would try a Cox Medallion and a Cox 7/3.5 prop. Also, I would be more inclined to use the Hitec 555 receiver. The medallion would provide a lot more usable power than the QZ. without the extremely high revs of a TD. The TD seems almost like overkill. I am assuming here that you want the aircraft to be able to fly in a somewhat scale manner.
Richard Say
1/2A forever

subarubrat

My Feedback: (1)

Does the Medallion come in a configuration like my TD, with a throttled carb? What about muffler use? I already have the TD on hand and it is fresh out of the box. If the medallion is a better choice I suppose I could find someone to swap with.

flyinrog

My Feedback: (1)

if you have a carbed td/rc .051 with muffler its worth much more than a medallion,,they have a cheapie muffler and a throttle ring on them...Rog

subarubrat

My Feedback: (1)

Thanks to everyone so much in this project, it is appreciated.

What is the key difference between the Medallion and the TD? Is it the porting and head? I know allot of guys over the years have built some good Cox parts combo motors. Can I keep the TD's better carb and overall build and use the Medallion cylinder and head and get medallion performance with TD tech? Or am I better off just ordering a medallion?

flyinrog

My Feedback: (1)

Kinda hard to describe, the Medallion is a tee dee with a throttle ring that is part of the muffler, and you control muffling(?) by sliding a ring across an opening on the muffler,,,use what you have...its the better setup...Rog

Richard Say

sabarubrat,
Not all Medallions came with the throttle ring. Some older Medallions did come with the coupled throttled carb and exhaust muffler throttle. Some examples of these can still be found on e-bay either new or used. You could probably engineer a swap with someone.
Richard Say

kdheath

Here are all of the Medallion 049 varieties. The throttled ones may be fairly rare. I can't recall ever seeing one for sale. But the exhaust sleeve version would be an easy parts swap.

The difference from the TeeDee is the front end, pretty obvious. The Medallion is a nicer sport engine than the TeeDee, less power but friendlier.

BMatthews

Medallion's have a simple round hole for the crankcase port that limits the intake timing compared to a TeeDee. Also the Medallions came with either a single bypass flute or a simple twin bypass flute cylinder while the TeeDees have the fancy triple drilled flutes with more bypass area.

What's the size and anticipated weight of your Cessnas? If it's in the 36 inch and 20 oz or less range I'd say a throttle equipped black widow will be fine. We just gotta find a sleeve for ya.

subarubrat

My Feedback: (1)

I have to throw everything on the scale and get a total weight. My goal for the plane is to have a short takeoff run so that I can take off in the baseball diamond and have good climbout. Although I am shooting for a scale flight speed I also want enough power for most aerobatics. Additionally I am wanting an external tank to get the longer flight times I am used to, good 10 min or so flights if possible. And I do need to run muffled. The medallion sounds like it will swing the right prop but the throttle and muffler solutions seem limited. Let me get back to you on a total all up weight.

Remby

My Feedback: (3)

The flight times you are looking for throws out a tanked reedie, only option is a killer bee, or the FRV Cox engines. The Medallions above show, third from the left, a throttle with muffler that fits your bill. Be aware the Medallion has been out of production for some time now, so look to the auctions to find that needed gem.
Remby

Tim Wiltse-RCU

subarubrat,

If you are wanting to leave it Cox powered the only real option here is a DickeyBird TeeDee conversion. The Medallion just won't get the job done here. And out of all of the choices the only good throttled Medallion is the one with the coupled exhaust throttle which if the one on the right end of kdheath's pictures. The so called muffler/throttle combo of the 3rd engine is a joke.
DickeyBird has taken alot of time and reworked the Cox TeeDee to have a very reliable throttle using a throttle sleeve and a reduced venturi bore. It will take some rework to do the mods on your end though. But the are easy to do. Now if you have a Cox RC 05 from the factory I would say either place it back in the box and keep it for when your kids go to college or sell it now( I have seen many for for over $150) and gather the parts for a DickeyBird TeeDee. The first version of the RC 05 is junk and that has been proven by many people here. The carb lacks an airbleed making the thing idle like my 427 Chevy with a tunnel ram in heavy traffic. Sitting around for a little while and when it's time to hit the throttle flame out.Not fun![]

Do a search here for the DickeyBird TD or maybe on of the others has the link already. I think you have started a very good project and be sure to keep us all posted.

LAter,
Tim

BMatthews

Every baseball diamond I've ever seen has an outfield attached. So really there's easily enough area to allow a perky but not rocket like climb. But the need for a throttle and muffler really cuts down the options. I hate to say it but the Norvel option is looking better and better.

subarubrat

My Feedback: (1)

After taking everyone's input into consideration, looking at prop charts and such, and given my experience with Norvel recently I decided to go Norvel. I have a Norvel in my LMH110 heli and it has a solid low RPM idle with good throttle transition and is fairly quite and that is using the throttle muffler setup. The Norvel I just got with my Kamdax mig ducted fan starts just as well and idles great. The .061 looks good although I am considering the .074 as well. I stuck the Cox R/C 051 up on ebay.

Man, if only there was a .09 4 stroke......