Sorry I had a typo. I stand corrected, the Moki 2.1 thread in Tachometer Readings talked of a 20X10 (not 22-10) in the 7-7500 rpm range. Just didnt proof read my math [X(]

They talk of the Moki Ultra 20/10 prop 7660 rpm on no nitro fuel.

Here is a quote from Scale Speed in that same thread" Hi Guys:
I have two Moki's and the 2.1 is definitely stronger. I am running a Moki 20-8 prop in a 1/3rd scale Pitts @ 15-1/2 lbs. and it turns 8500 on the ground using Byron 5% with 18% oil. I have unlimited vertical and can pull up out of a hover with easy. More than enough power for this airframe. My 1.8 is in a Hanger 9 Cap and what a combination. Knife-edge loops aren't a problem with a Moki 18-8 prop. Scale Speed"

Now the question reapplied for an 85-87 inch platform that might easily balance and to what 3D capacity might it have. Otherwise, I might wait a few more months to sell the moki and come up with extra cash for gasser.

DP...I hope you weren't referring to my bad pics. I just hooked them up to get a quick pic. Here's a better pic showing full deflection using the CH horns.

That's much better... looks about 45 degrees to me...

Okay, if you can keep the weight to 15-1/2 lbs and if the Moki can turn a 20-8 at 8500 rpm you'll have a great setup. You may even benefit with a 22x8 and lower rpm, as long as it stays over 7000, but I don't know how the Moki will react to the larger load. I would say with this setup you'll be able to do anything in the book.

Since you already have the Moki, why don't you try and get your own rpm data, say with a 20x8 and 22x8 Menz or MSC or Mejzlik prop? Real numbers with your engine and prop combo will eliminate some of the unknown.

Good pics! I am glad to see the CH horns worked out... I was little worried...

Maudib - No doubt about needing shorter arms for longer throws.. for whatever reason the rocket city horns definitely need to be taller to achieve the 45* displacement... It would be easy for me to convert to the CH horns and I still might. That should be worth another ounce in the tail... !


Sparhawk - you will definitely be doing some surgery on that cowl. Don't worry though - it is heavy so cutting it away saves weight. I cut almost the entire bottom out of mine, and then mounted 2 small wood blocks with screws to support it from flapping on the bottom. This is good for the DA air supply, good for weight, and you don't even really see it. You want a lot more air coming out than going in..

I will try to take a picture tonight and post it here.

DP

I checked with the protractor --- throw is about 52* !!!!

ed42d-RCU - what are the lengths on the servo horns and who makes them?

Spar

They look like the 1.25" SWB horns... http://www.swbmfg.com

yup...1.25" SWB horns. They even had them at my LHS.

Ed

Thanks!

Spar

My DA arrived today.

Time to start the break-in!



Does anyone know how much to offset the firewall to get the 3* of right thrust?

Hi dirtypool,

I can give you my exact dimensions when I get home from work. But it looks close to 10mm.

Spar

Do what all the "good guys" seem to be doing these days... don't put thrust in your firewall and use rudder-throttle mix to compensate... compensates for P-Factor on throttle advance and ELIMINATES tracking problems at low speed or idle!! I tried it per Chip Hyde's suggestion and MAN does it work nice. I use a 2=3% right mix on throttle advance and a 1% left mix on idle... amazing how straight the plane tracks now. My firewall has 0* thrust so my cowl is straight as an arrow!!

I have always battled low speed trim and used left rudder to offset the right engine thrust on downlines and idle entry into stalls... NO MORE!!

On these planes with big rudders, this works beautifully.. !

DP

Have you tried that on your Ultra Stick DP? I've always thought of that as a band-aid, but if you think about it, builing right thrust into the firewall is the real band-aid as this setting can only be correct at one throttle setting!

My Ultra Stick also has 0 degrees right thrust. I find this very nicely done on the 10X but it probably requires that radio to make it work the best (expos, tracerate and mixing are all engaged)

I did not do this on the Carden.. figured why experiment with something that is well proven by Dennis, but everything else has seemed to respond well to it so the next Carden I do may even have zero!

So far my BME edge and USL have zero and it has worked well. I really really hated having to tear off cowls and shims every time to adjust incidence... now I use my radio!

Chip Hyde said that even on his last 40+ plane he used only 1* of right thrust and used the radio to take care of the rest... !
I really like the 1* of LEFT rudder on idle.. it totally eliminates the drift common on low speed inverted flight.. !

It took me some playing and about 30 landings before I was able to get the plane tuned just right.. but it was a lot more fun than adding shims!

DP

Excellent! That makes it easier for me.

I use a 9C so I will make sure I can mix that in ok.

Just flipping through my DA manual. It says to use Nicads for the ignition pack. Are NiMH ok? 4.8 or 6 volt?

Man, I am having trouble finding Lawnboy Ashless oil. DA said any quality petroleum oil will be fine for break in but most of what I see is a blend at least. I have some old (6 years) 2 cycle oil at home that is petroleum. That old stuff is 32:1 though.
What should I do?

I would be lost without this forum!!!!!! ( actually I never would have even bought a large scale plane without this forum)

These engine manufacturers need to start specifying oils that are available world-wide, or start selling the oil themselves. Lawn Boy is pretty much impossible to find/acquire in California.

The DA ignition accepts a 6 volt pack so that's what I aim for... (I end up going lion with a 6 volt regulator)

I'm sure you guys have tried here but if you have a Lowe's or Home Depot you may find it in thier lawn mower section...

If you don't find any and want some, I'd be glad to pick up a few cans and mail 'em to ya... They are only like $2 a can and makes two gallons at 32:1...

Maudib,

I may take you up on that offer. My friend is going nuts looking for Lawn Boy for his DA-100. When I see him this weekend I'll pass on the offer. Thanks again.

dirtypool - if you go with the 0* thrust, then obviously you won't need the measurement, but for those that do, if you measure in 11mm in on the right fuse side, that should put you at the 3* mark.

Well, mine is at 3* and my cowl is also straight as an arrow. There is a built in thrust angle on the front of the cowl that makes it easy to have the spinner be parallel to the cowl.... so if you have a 0* firewall, and 0* thrustline on the engine, then this part of the cowl must look off-kilter (sp?).

Spar

You should be able to get lawn boy ashless at any ACE hardware in the USA and Canada. I have never had a problem getting it, even in CA. That said, Bel-Ray S2 and Pennzoil petroleum based oils are also excellent.
I personally like the Bel-Ray - it does not have that "burning pencil" smell to it like the lawn boy, I use the LawnBoy though as that is what everyone says provides the fastest run-in.. my zenoah really likes it too!

Sparhawk - my cowl is cut straight, usually you simply mount it at a slight angle or mount it straight and let the prop flange look crooked. Mine is perfectly aligned at 0 degrees..


The best combo for the DA ignition is EITHER a 4 cell Nicad / NiMH of adequate capacity 1200 mAh + OR a Lithium Ion regulated at 5.1 volts DO NOT let the voltage go above 6V.. you will greatly shorten the life of your ignition. If you use an unregulated 5-cell NiMh you will go over 6V!! I use Fromeco Li-Ion 2200 mah ($22) and a duralite fail safe 5.1V regulator ($35) money well spent. If you don't want to spend $57 on batteries go with a 4 cell NiMh from hangtimes hobbies, a 1500 maH is about $25 bucks. It weighs a little more, but its cheap!

I went with Li-Ion on this plane as I needed the weight savings, but I use the Relions on everything.. it makes life a lot easier when you only have one type of battery and charger! Even my 10X has a Li-Ion battery.

FYI - my 2200 mah li-Ion Ignition battery has about 21 flights on it and it still has 7.2V left under a .5A load. You don't need a huge ign battery!

DP

Your cowl must be different than mine then, as mine is molded such that the prop flange is already angled for this. Putting the firewall and motor at 0* will make this look sick.

See pic:

Spar

Tried my local Lowes, Home Depot, OSH, Mower shop, another mower shop, ACE hardware and nobody has it in stock.

I will see if I can get some ordered. A family friend owns a mower shop about an hour away.

I tried four different ACE Hardwares, at least three different Lowess, at least three different Home Depot's, every Auto Zone, Pep Boys, Napa, and Kragan Auto Parts store in my area (and there's a lot of them) a couple different Sears, called a few lawn mower shops, checked with the local motorcycle dealers (Honda, Yamaha, etc.) tried Von's, Ralph's and Albertson's, even tried my next door neighbor, and nobody has it.

Awe come on man... don't give up til you've given a resonable effort...

Let me know... it grows on trees around here.


Well...

not really...

Let me see if I can get some. If so, maybe I can split a case with ptgarcia and his flying buddies.

Rob