Sperry Messenger

NEW222 wrote:Never built it, but I do have the plans if you want.

thanks friend! I see that the map is here:
https://outerzone.co.uk/plan_details.asp?ID=1281
Do you have this one?

Yep. That's the one I have.

NEW222 wrote:Yep. That's the one I have.

Oh, okay, thanks friend, for your predisposition!

Hey Mauricio,

The plan for the Sperry Messenger was published as a full size plan by a fellow named Dave Robelen (one of my model airplane heroes) in the June, 1969 issue of Model Airplane News.

In 1993, I built a slightly enlarged (I think 10%) version, that was just barely big enough to use two Cannon Servos that had been cut down to fit.  Powered by a Cox Tee Dee .010, it was pretty fast, but it flew nicely once I got the control throws adjusted to minimum movement...that elevator DOES NOT need much deflection to be effective!

I still have it, and intend to put a bellcrank in it and fly it as a control liner.





















I sent Dave a note detailing my experiences with his little plane and was VERY pleased to receive this reply, which is now kept with the other mementos of my Model Airplane Heroes.

What a cool letter Kim! Was there further correspondence regarding the Piet?

roddie wrote:What a cool letter Kim! Was there further correspondence regarding the Piet?

Thanks Roddie !!!

Well, I THOUGHT I had further notes, but can't seem to find them.  I have a separate notebook just for the Sperry Messenger, with all notes and photos even remotely involving the plane.



I'm pretty sure that we traded notes---both on the dimensions of my Piet and his research/experimenting with throttle-equipped .010's.

Gonna drag out some more albums and see if I can find them!

Kim wrote:Hey Mauricio,

The plan for the Sperry Messenger was published as a full size plan by a fellow named Dave Robelen (one of my model airplane heroes) in the June, 1969 issue of Model Airplane News.

In 1993, I built a slightly enlarged (I think 10%) version, that was just barely big enough to use two Cannon Servos that had been cut down to fit.  Powered by a Cox Tee Dee .010, it was pretty fast, but it flew nicely once I got the control throws adjusted to minimum movement...that elevator DOES NOT need much deflection to be effective!

I still have it, and intend to put a bellcrank in it and fly it as a control liner.

I sent Dave a note detailing my experiences with his little plane and was VERY pleased to receive this reply, which is now kept with the other mementos of my Model Airplane Heroes.

Hello Kim, thank you for all this information, and for sharing that valuable letter, a treasure really!
I find this model interesting, surely at some point start to make one.
I have some questions for you:
1) I see that you have decorated the model, have you painted it? or did you use some kind of coating?
2) I see the .010 with a rc carburetor, is there a store in the USA where that carburetor is sold? for TD 010 and TD 020 ??
Thanks for your time!

MauricioB wrote:

Kim wrote:Hey Mauricio,

The plan for the Sperry Messenger was published as a full size plan by a fellow named Dave Robelen (one of my model airplane heroes) in the June, 1969 issue of Model Airplane News.

In 1993, I built a slightly enlarged (I think 10%) version, that was just barely big enough to use two Cannon Servos that had been cut down to fit.  Powered by a Cox Tee Dee .010, it was pretty fast, but it flew nicely once I got the control throws adjusted to minimum movement...that elevator DOES NOT need much deflection to be effective!

I still have it, and intend to put a bellcrank in it and fly it as a control liner.

I sent Dave a note detailing my experiences with his little plane and was VERY pleased to receive this reply, which is now kept with the other mementos of my Model Airplane Heroes.

Hello Kim, thank you for all this information, and for sharing that valuable letter, a treasure really!
I find this model interesting, surely at some point start to make one.
I have some questions for you:
1) I see that you have decorated the model, have you painted it? or did you use some kind of coating?
2) I see the .010 with a rc carburetor, is there a store in the USA where that carburetor is sold? for TD 010 and TD 020 ??
Thanks for your time!

Hey Mauricio,

1.  At the time, I was still using Aerogloss-brand Butyrate Dope (now use Brodaks pretty-much exclusively), and followed Dave's use of it to 'warp' the airfoil into the Sperry's sheet-balsa wings:



2.  I have seen the .010 & .020 throttles many times on the internet, but have not seen the real thing.  Ebay may be an option, and members here may know of a source.

A letter from Dave Robelen!!!   You are my hero.

Do you have a closer view of that TD .010 RC carb?
Using the posted if I blow it up to see it starts to blur out.

[quote="1/2A Nut"]Do you have a closer view of that TD .010 RC carb?
Using the posted if I blow it up to see it starts to blur out.

Here you go:

Thank you Kim mucho betters

Great thread. Interesting stuff being shared. Thanks, fellas!

I really like this little plane cause it will fly in a small area (my back field) I have a .010 that needs some attention with the new parts i bought some time back . Not to mention Batjac sent me a computer radio i need to use as i promised !?! Futaba T6XH s 12" is very small too , maybe a scale up to 13.5 " ?/ I dont have a exhaust throttle so maybe the 14" w/S would help in slowing it down , Use to have a pulse single channel long time back but sure it's gone now Just thinking out loud ...  
You get the idea , There is 2-3 acres with trees ,But the trees are beeing thin right now

Kim wrote:

1/2A Nut wrote:Do you have a closer view of that TD .010 RC carb?
Using the posted if I blow it up to see it starts to blur out.

Here you go:

that beautiful carburetor Kim !! ... it would be great to get a couple of them !!

Indeed. I love running .010s and have always wished to throttle one. When I first got into RC flying, the exhaust throttle sleeves/cylinder sets could still be seen for sale occasionally. When I finally decided to jump in, they were all gone. The only thing cooler than a tiny engine is a tiny RC engine!

Throttle sleeve works really well with the TD .010
Here is a vid I made doing a bench test.



AmpAbuser
Published on Feb 1, 2016

Cox TD.010 with throttle sleeve
20% nitro and oil / Static Max 28,082 rpm.
Best reads 11.7k idle
Cox .010 prop modified

1/2A Nut wrote:Throttle sleeve works really well with the TD .010
Here is a vid I made doing a bench test.



AmpAbuser
Published on Feb 1, 2016

Cox TD.010 with throttle sleeve
20% nitro and oil / Static Max 28,082 rpm.
Best reads 11.7k idle
Cox .010 prop modified

Yes friend, you have done a great job, and it obviously works very well. It gives me "something" todar the cylinder sweeping the skirt ... I'm very afraid of damaging the cylinder, and as I have no spare, I do not want to risk ... if I had an extra cylinder, maybe I would try.
Getting the carburetor would be ideal, that way there is no risk of irreparable damage.
Great GREEN for you my good friend!

Thank you = ) the grinding off of the lower skirt on the cylinder is the only simple
way to slide on a throttle sleeve. You can make your own carb, the trick is making the
needle valve small enough to work well with the carb.

1/2A Nut wrote:Thank you = )  the grinding off of the lower skirt on the cylinder is the only simple
way to slide on a throttle sleeve. You can make your own carb, the trick is making the
needle valve small enough to work well with the carb.

Yes, I thought about making a carburetor, but here I do not have the tools small enough to make threads and create a needle valve.
Also, I do not think I'll get the tap to make the thread of the carburetor body that threads in the carter boody ..... for all this, I better let the idea go ...
If you remove the skirt of the cylinder, my question is: does not vary the height of the cylinder when adjusting with the crankcase, that is, the skirt is not a necessary stop?

I agree. And yes, those .010 cylinders seem impossible to buy now. I have no spares to risk, either. I've had my eyes peeled for years for a viable throttle option. Skaliwag at Select Hobbies once had some throttle cylinder/sleeve sets made by a machinist friend, but they are long gone .

There is always a way, never give up that is what it takes to fight for your fun

With the lower skirt ground off you still have enough cylinder diameter like a TD .049
to catch the crank case see photos. I covered the threads with tape then filed off the
skirt with steady care. Note the baked on castor oil over time this helps for a tighter
seal and lower idle so let it collect. I put a groove around the sleeve then used piano
wire loop smaller in dia. of the sleeve it snapped into to the groove and holds well.
Small arm extension with another small wire loop with tubing inserted for a slop free
use with the throttle push rod. It's easy to do just takes time. I used reading glasses
to improve my vision during the fabrication as these are very small parts.





If you can source a suitable C clip the effort mimics the familiar for a nice clean setup.

Great work !!!