JohnVH

My Feedback: (38)

After watching all the video's on the site http://www.jcrc.com/PizzaBoxFlyer.htm
Ive got to build one! looks hilarious!!!!!!!!!!!!

James Goss

Flipper

I know the excitement you are talking about when you describe the vertical landing. Nothing can beat this maneuver and it is one of the most graceful stunts we can do. Having the landing gear opens up the door for a lot of fun and pleasure. I have deleted my tail wheel in favor of a tailskid made from 3/32 music wire. It will not change anything in the way your plane handles on the ground, but you will like it better than the wheel. After you make that first vertical landing you are hooked. You will spend most of your time doing that maneuver and a lot of nose-up flying about three feet off the ground. The tail end of your plane becomes the business end and the tail wheel is not tough enough. We need something that will not give any when the tail hits the ground. I went through several before I decided to switch over to the skid from 3/32 wire. It will handle any of your tail walking now. Good luck and happy vertical landings. James Goss

James Goss

If you haven’t tried a vertical landing you are missing one of the best maneuvers our flat planes can do. First you must have at least 1/8 inch landing gear and a tailskid built from 3/32 music wire. Build your gear long enough so the prop will not hit the ground if your plane bounces in this maneuver. The best vertical landings are created by bringing in the plane at about 40 feet above the runway and at a moderate speed. Stall the plane by turning up its nose and enter a hover. Let the plane settle and stabilize somewhat and then begin the descending pattern. To achieve this you reduce the throttle and see how fast the plane drops. You control the drop by throttle and elevator. If the plane is dropping too fast give it more engine power or less elevator. Of course if you reduce the elevator the plane might move forward unless you reduce throttle also. Most of the time you will need to use the rudder to keep the plane in the direction you want, especially on the windy days. It doesn’t take long to work the stamp to within a foot of the ground. Give it a little power and let the tail softly touch the ground. As it begins to timber (fall to the ground) bring up the power and she will sit down just as pretty as you please. Give it full throttle and she will be back in the air in less that five feet.

Flipper

My Feedback: (3)

Thanks for the tip James, I hit the prop on a bounce last night so I will need to add some longer gear before long and will probably go to the tail skid. I replaced the 40 LA with a 40 FX and increased the throws tonight so I will have a little more power for the crazy stuff. I was working the LA a bit to hard, it's tongue was hanging out. Jeff

James Goss

Flipper

I was running a .46 LA a while back and it had plenty of power to fly the stamp, but when I changed to a TT .36 I was amazed at some of the new things the plane would do. There is nothing like having the brute power when you need it. Even more important is having the quick engine response when you are three inches off the ground and need to pull up in a hurry. Sometimes when these little flat planes start to go down it requires a good bit of thrust to prevent them from hitting mother earth.

Flipper

My Feedback: (3)

James,
I had a couple of close calls that more power would have helped out on, so that is why I did the engine upgrade. I showed the plane to a fellow club member and he took off for home to build his with a piece of my coroplast.

JohnVH

My Feedback: (38)

so, if its power, how about my TT.46 pro on one?

James Goss

I am installing an os .46 fx on my newest version of my stamp. It is an inline twin rudder with one rudder in the rear and another up front. I will let you know how it comes out after I try it Saturday if not before. A friend of mine has an Enya 45 on a stamp I built for him and is going to try it this Sunday. There is nothing wrong with more power when you need it. I am thinking about building a four-foot square stamp with a gas engine. I think it will be even more stable and a heck of a lot of fun. I have a new US 41 that might be ok, but it is pretty heavy. On the other hand, a flat plane that size may need more weight up front anyway.

JohnVH

My Feedback: (38)

Oh, a gasser stamp would be neat! Like to see you hand launch it! haha

Keep us posted, Im out after work looking for materials

James Goss

Here is a picture of the inline twin rudder stamp. With the OS .46 FX it weighs 3 lbs and 15 ounces. Should not have any trouble getting off the ground at that weight with a 12.25 x 3.75 prop, but I wonder how well it will fly and how sensitive the rudder will be. I have always wanted to try this set up and with the stamp it is the ideal plane to try it on because it is so easy to install and couple the rudders together. It may even improve the knife-edge ability of the stamp. If this works out ok I have been thinking about trying the same setup, but with a solid piece of coroplast running from front to rear instead of two vertical fins. This should really improve the knife-edge without use of wing tips. There is so many things I want to try with these little flat planes I just can’t get around to it fast enough.

Flipper

My Feedback: (3)

Tried the 40FX tonight and hated every minute of it! It had plenty of power but added to much weight to fly around low and slow like with the 40LA, so I switched it back when I got home. Had a nice soil penetration test from about 75' up and all it did was break a prop, these things are tough. Now a 25FX might be a good choice, I need to see if it has about the same weight as the 40LA.

JohnVH

My Feedback: (38)

I got materials, only had 4mm 24x20" hope that will work, what do you guys think?

Flipper

My Feedback: (3)

When my coroplast came from harborsales.com it was 24 1/2 x 48" and and the rest of the sheet was in 2 pieces 35 1/2 x 48" so I just squared the 24 1/2 off. So mine is 24 1/2 x 24 1/2. What will the width be if the grain is running tip to tip? 20" or 24". I would think it would be better with a 24" span. James has done the most as for as different sizes though.

Dave McDonald

My Feedback: (19)

Flipper,
The 40LA weighs just slightly more than the 25FX.

I agree 100% with you that the power of the ball bearing 40 size engines is nice.....but the weight penalty really kills the slow flight and agility of the 24x24 PBF/Postage Stamp/Pizza Box planes. IMHO, once the dry weight goes over about 2 1/2 pounds on the 24x24 planes, the overall flying performance really starts to suffer, and they aren't as much fun to fly.

At less than 2 lbs. 1 oz., my Norvel 25 powered PBF is more fun to fly than my 2 lbs. 8 oz. PBF with an OS 40FP.



JohnVH,
I'd suggest holding out for a 24x24 piece of coroplast. Unless you are going to use a very lightweight engine and radio, I think you are going to be disappointed with a 24x20 flat flying wing due to the considerable reduction in wing area.

JohnVH

My Feedback: (38)

How about if I put my webra .28 on it? save some weight maybe? OR, I can hinge on the 4" ailerons to make it a full 24 square. Hmm

The grain right now runs the 24" way

Dave McDonald

My Feedback: (19)

Great idea! With the flutes running 24", adding 4" elevons would work out perfect!

But if I were you, I'd still use that Webra 28 on a 24x24 size plane. If you want more power, use a mousse can pipe to keep the weight down.

James Goss

Dave,

I think you are 100 % correct about the weight factor. The fun and weight are inversely proportional to each other and as the weight goes up, the fun goes down. We will refer to this as “Dave’s Law” from now on. I have never had a stamp as light as 2 lb 1 oz because I have always used landing gear. I am going to build one today without the gear, but I don’t have a Norvel .25 in stock. I will get one soon and until then I will use a hot little magnum .28, I have several of them. Even though I have tons of these flat planes I look forward to this lightweight project with no landing gear because it is a challenge to achieve such a lightweight plane.

JohnVH

My Feedback: (38)

So what is the optimum engine for these? .25's? .30's? .40's?
any specific brands? how about a MVVS .21 or .27

Thanks

Flipper

My Feedback: (3)

Dave, which Norvel is the best for this the BB or not? My wife is going to kill me, now I need a Norvel 25, a Saito 72, a Whiplash! hehehehe

Dave McDonald

My Feedback: (19)

Flipper,
My Norvel Big Mig 25 bushing was a prize from a combat contest so I didn't really choose the bushing version over the ball bearing version on purpose. However, there were a lot of combat flyers at that meet who had tried both, and they felt that the ball bearing version wasn't worth the extra cost since the bushing version was within a couple hundred RPMs of it. Based on my own experiences with the bushing Norvel 25, I wouldn't hesitate to recommend it. It's really a jewel!



JohnVH,
Hopefully James will chime in here too, but here's my thoughts on PBF engines:

The most important engine requirement for a PBF is that it must run well at ALL throttle positions, and respond quickly and cleanly to any change in throttle position, no matter how small. An engine that loads up, stumbles, hesitates, or flames out at partial throttle, or during throttle changes will take away about 90% of the fun of flying these type of planes.

The next most important engine quality is that it must be lightweight. The TT 42GP is the heaviest engine I would use on a PBF, and it only weighs 12.5 ounces including the muffler. The Norvel Big Mig 25 isn't as powerful, but it only weighs 8 ounces including the muffler.......thus saving 4.5 ounces of dead weight.

Finally, the more powerful the engine, the better.....as long as you don't sacrifice the throttling and lightweight qualities to get more power. This is one of the areas that makes a mousse can pipe (MCP) so attractive because a MCP is usually lighter than the stock muffler, adds considerable power, and usually improves the throttling qualities to boot! Plus it keeps the exhaust glop away from the radio.

Of the engines we've tried around here in PBFs, the standouts have been the Norvel 25 with lightweight radio gear, and the TT 42GP w/MCP when using standard radio gear. The OS 40FP has also worked out very well in a PBF.....especially because of it's extremely good throttling qualities and light weight.

I've never seen a MVVS 21 or 27 around here yet so I won't guess as to how well they would work on a PBF. But you should be able to get an idea of how well they will work by considering their precision throttling qualities, their weight, and their power output......in that order.

(sorry this post got so long, but choosing an engine really boils down to more of a personal preference than hard science.)

Flipper

My Feedback: (3)

Thanks, Dave

propcut

Dave
Took the PBF to the field today and what a hit it was. I know there will be 5 more at the field within a week. The gang loved it. I was asked to mail your web site to seven different people to day. Man your gonna be getting alot of hits. Did you get the mail about explaining the corn finder? The PBF was the only thing I flew today even though I had 3 planes with me. What a neat new toy!
Thanks, Bruce (propcut)

Dave McDonald

My Feedback: (19)

propcut,
I'm glad to hear that your PBF was a success! I know what you mean about getting hooked on flying the PBF and never bothering to fly anything else. This thing is addictive!

Thanks for the explanation about the "corn finder"! Once you explained it.......it was obvious!

Feel free to email my PBF web page to anybody that wants to see it. This thing is too much fun to keep it a secret!

James Goss

I have just returned from our flying field today where I spent all morning and part of the evening. I gave my new twin inline rudder a test fly and it was a handful at first. I knew it was nose heavy with the .46 engine, but I will need to add about 1.5 oz to the tail before its next flight. I didn’t get a second flight because I was teaching a new pilot on the trainer cord when his transmitter battery went to zero volts and his plane flew around for the longest on its own with max throttle. It is a sad feeling to just stand there and watch when you know what is going to eventually happen. It finally went down in a cornfield and we have yet to find it. We plan to look for it again early tomorrow morning.

The twin inline rudder really does respond well on the ground, I know that for sure. Its turning ability has quadrupled, even though the regular Stamp turns ok with a little speed built up. I will give it a few more tests to see how the aerobatics work out and then probably install a smaller engine if it performs well. I just wanted to see how they would fly with the .46 because a lot of guys are asking me about the maximum engine size.

It was very windy at the field today and the little Stamp with the TT .36 performed quite well. Some members were amazed at how well it flew in the wind. That is another question I am often ask about, how does it fly in the wind? Well Dave I am sure you will agree that these flat planes are great windy day planes. Sure they are like a sail on a ship when they are hovering, and the wind pushes them around, but this just adds to the overall fun and excitement.

I delivered three more Stamps to the club members today so the numbers are growing fast. I am building them free of charge so the members can see how much fun they really are to fly. The only thing wrong is that they are all the same color. With four or five in the air at the same time it might get to really be fun. It might be like the old shell and pea game where you try to guess which shell the pea is under.

Most everyone in our club and in the surrounding area is going to use an engine in the neighborhood of the TT .36 because mine works so well with it. Of course some will be smaller and some larger, but they will average out around the 36 engine. I am sure there are many fine engines for our little flat planes and with time we will probably see a variety of engines in use with everyone swearing by them. That is a good feature about these planes; just about any small engine will fly them with success.

Flipper

My Feedback: (3)

I put the 40LA back on and flew mine quite a bit this morning and decided the APC 10x3 worked well on this engine and plane. The velcro is great for the battery and reciever because I was able to play around with the CG and moved it back and really got a great hover and vertical landing. I also bent up a new gear to keep the prop off the ground a little better. I found when hovering in a slight breeze that kept changing from east to south east the plane would change with the wind without even starting to fall out of the hover. Very fun!