tevans55

Shihtzutan-
Sorry to hear about the maiden on your Spit. That is a beautiful plane and I know what you went through. I am on my second exhaust system in mine. I am using an OS 120 AX with a JTEC wrap around muffler. Do you think that the length and multiple bends in your exhaust may have resulted in less performance from your Saito? I added heater hose to mine and lost about 300 RPM from the top end.

Aluminum Overcast

The usual problem with scale is exhaust and retracts /  ground handling.  Forever chasing solutions to those issues. Were you getting muffler pressure to the tank? Home made exhausts are notorious for loosing pressure during flight (leaks and loosening) causing erratic engine performance and flameouts.

Shihtzutan

My exhaust worked perfectly, my power curve was dependable and strong. One tip to whomever wants to try something like this though; the joints must be braised, not soldered.Silver solder melted and I had to re-do the joints. My tank pressure was taken from thecopper tee at a place where the tubing goes from3/8 to 1/4 ID where it split, my tank pressure was good. Because theengine was still being broken-in,I did not peak it.I ran itrich deliberately.Power has to be applied slowly toprevent nose over, but even at full throttle it lacked the authority to get me out oftrouble.I've got a video of it running on the ground. I'll post it later so you can hear it.The Satio 1.25 isn't a good choice for grass field with a Spitfire with all the bells and whistles on it. It weighed 17lbs (as weighed with an electronic fish scale), but over two pounds if it was lead ballast. My Satio 1.50 is heavier and more powerful, I figure ifI'm going to carry the weight, it may as well be usable;I should beable to removea pound of lead by doing this.

Johnnie Red

Hey bucho

The Saito 125 is an engine for sport light airplanes (like Extra or Yak etc.)
In use for the heavier warbirds you must pick up heavier engines like a SC-180 FS which with the 30cc glow will help youswing a biger prop plus will give you the extra ballast to the nose.
In the KMP/YT corsair that I have and weights about 8kilos,plus my KMP/YT P-47 I am using the SC-180 FS in both with excellent results. The fuel that I am using is a standard 4stroke Byron Fuel with 15% Nitro. Though I have to mention that Ihad to add even more ballast to the nose (approx. 800grams of lead).
All these birds are ballancing correctly at 1/4 of the airfoil, empty (no fuel), inverted with the retracts in the retracted position.
Also by the time that you setthe airplanetogether, you all must consider the following. All the ARF's are made in order to fit a general point average of the target group that they are refering to. That means that to secure your satisfaction with them you have to be an experienced flyier and also to have building skills in order to make custom reienforcments (especially around the main spars, leading edge andthe retract area by using glasscloth and poxy.). It doesn't matter how experienced in flying you are. It is a matter of timeuntilm youmake a hard landing and if the wings are not reienforced then you will face the facts.
There is no doubt that KMP is making a Best Value for Money product and they realy boost up the airmodelling fun. Their planes fly with authority;and they aregiving you the sense that you fly a bigger plane (Takeoffs are giving the sense of heavy controls).
ALWAYS take upon your concideration that these planes must land on flaps. A no flaps landing most of the times ends up with destroyed retracts and retract wells!!! Only if the headwind is more than 12knots then you may try a gentle no flap landing!!!

Happy flights to everyone!
JR

djay

My version 1 Spit has an OS 1.20 standard fs in it, weighs 17lb, which includes a 2lb+ lump of lead in the nose, and that flies no problem.
My TF Mentor weighs 19lb, and flies with the same engine ok.
My World Models Thunderbolt has the Saito 1.25 engine in it and this flies very well with a 16x6 prop. The saito definetly turns out more power then the OS and is perfect for the heavier warbirds, with the right prop.
The SC 1.80 is a heavy plodder of an engine. I have one in a large scale WW1 Fokker Eindecker, and it will power this OK, but it does not match the power of the OS 1.20 or the Saito. it is a reliable general purpose engine. Very good value for money.

If you want power go for a YS engine, the pumped versions (DZ) are simplicity to set up and do not require a pressurised tank. I have a YS 110, and this thing is pure power, and a YS 140 DZ which turns out over 1bhp more then the OS 120, and is the same size and the same mounting holes.

You do not have to use flaps for landing any of these models, it is purley dependant on how long your runway is or if you just like to use them. I often land my Spit and my other models with no flaps, and no headwind, it all depends on how good a flyer you are, and the field you fly in.
From my experience there is no difference in the landing charateristics, other then a little more forward speed,but then I can give my models a long flat uninterupted approach to the runway.

JR can you elaborate on your statements about all ARF's require building skills to reinforce them, why? Are you refering to a specific manufacturer or type, or all in general?

All my multiple ARF's with the exception of the YT/KMP version 2 spitfire have been fine and not required any reinforcements. I have at least 15 ARF's from small electric to large scale warbirds which are years old, without any structural failures, even after unscheduled landings.
The Spit on the other hand, had two fuses disintegrate and the wing literally fall apart during normal flying.. No amount of reinforcement could possibly have saved it. The version 1 is not suffering from this.

Keep at it shihzutan, it will be worth it once you get it airborne. I find the Spit very very easy to fly, no vices.

Darryl

kinverflyer

Not sure why your Spitfire is coming out at 17lb, friend of mine just finished his with a Laser 1.50 up front and it weighs 12.5lb and flies like a dream.

djay

For some reason it just needs tons of lead in the nose, even though it has been built as light as posible with all the radio gear forward. The version 2 came out around 12 -13lbs and that was built a bit heavier, with tons of fibreglass reinforcemnt inside it.

Most strange.

But it flies well.

Darryl

Shihtzutan

Glad to hear 17 lbs is normal. I'll definately keep it. The Mk XIV is my favorite and I bought it to be a flier. The 1.50 should solve my grass airfield problem; off a hard surface the 1.25 would have easily done it. Running out of runway didn't help either. It's all fixed now; moved two more servos forward while I was at it, and rather than plumb a new scale exhaust, I went with the stock muffler this time and deleted the remote glow. The scale exhaust was impressive, but very messy; it's one of those "careful what you wish for" things. New pics will be comming soon.

Johnnie Red

Dear djay

I respect your opinion about a no flap landing. Though what I am saying is that, a no flaps landing is increasing the stress of the airplane through the time. I have airplanes 15years and 20 years old, that I wouldn't have by now if I didn't use the flaps. The extra speed that you need in order to make a no flaps landing will definately affect your planes life cycle. Esspecialy for big warbirds.

About my comments for reinforcing the ARF's. I refer to all the ARF's. This is said cause I like to affect the final outline by adding bit's and pieces to make it more scale in appearance. (Rivets, different paintjobs, full body pilots, scale cockpits etc.) that most of the time are adding weight to the final product. All these plus that most of the ARF's are made in the sense of minimum weight and minimum use of bonding matterials. This happens in all the means of production in order to secure the minimum retail price possible.
When we make our own scratchbuilt plane, we use glues or any kinda matterial in excess cause we make our airplanes to fit our flying airmodelling standards and we do not handle a production zone in order to make our living.

The proof of my saying comes out from my knowledge and experteese through building and flying, not only in weekends but also in competitions the last 25years.

Always - no matter how good pilot you are - keep in mind a nice saying of one of my buddies here in GR. He said once (and in my opinion he is absolutely right..)
"There are 2 kinda planes in airmodelling. The ones that are going to break and the ones that are already broken..!"

I wish you all ... Happy flights
J.R.

Shihtzutan

Well, OK, I'll chime in. I'm quite the ARF kit basher and I'd rather build a kit than go with an ARF, but alas kits are becoming scarce and bashing seems to be inevitable. I wring out all my aircraft, I love the rush! I've also had them for years and fly them on windy days. The longevity of my models has a lot to do with maintenance in my humble opinion. Wood by it nature is very fatigue resistant; a properly balance prop smoothes vibration considerably. The flap thing is a little over the top, for me. I fly full scale as well, a flapped landing isn't very different than a no flap landing, in fact no flaps are always smoother. When the plane decides to quit flying all dirty and flaps handing out, there is always a definitive settling on the gear. My warbird models need the forward momentum and elevator authority to overcome the drag on the grass field landings; flaps or no, forward momentum is needed. There is little difference.

Chris Nicastro

My Feedback: (3)

Anyone interested in a NIB Spit KIT??? PM me, asking $300 plus shipping in US.

Chris

Johnnie Red

Well Shihtzutan......

Since you say that you fly full scale...can you tell us why in full scale planes 95% of the landings are done with flaps? (And I am not talking for piper cubs here..!)

tevans55

JR and Shihtzutan-
I hear what you guys are saying. I think flaps are a tool that a pilot uses to create lift at a slower speed when needed. When I land my KMP Spit on our grass runway I don't use the flaps in order to keep the speed up for elevator control due to the increased drag the grass puts on the wheels promoting a nose over which is what Shihtzutan is talking about I think. My plane stops in the grass in about 100 feet. If I use the same plane on our paved runway I have to use flaps to slow the forward momentum by creating the same amount of lift at a slower speed. I don't have the grass drag problem but it takes me about 500 feet to stop. I always use the flaps on my B-25 for speed control on landing but only on take off for short fields. My Corsair has no flaps so I enjoy landing it on grass to slow it down. Just my opinion but I think flaps...and the amount of flaps should be based on need for the conditions present.

Chris Nicastro

My Feedback: (3)

Full scale and model comparisons are very hard to make. Full scale passenger planes are very heavy and loads vary every flight. Ariports are as small as can be but able to accomodate certain plane types. For this reason passenger planes have to use flaps in order to make short landings and get off the runway as quickly as possible. The sooner a plane is off the runway the sooner another can land or take off, thats the economics of an airport. Otherwise look at an aircraft like the Shuttle or experimental planes that land in the desert they dont use much flaps and come in like a meteor. In addition there are parameters and specs that certain things like tires will work within. So if a tire for a 737 is rated at 175MPH max speed a pilot has to know to land or take off well within the parameters of his plane. Again there is a need there for flaps to stay withinthe configuration for landing a particular plane.
For us we have generally lightly loaded aircraft. As a model pilot its up to your discretion if you would like to use flaps or maybe there is no other choice because of the field or type of plane. To say every plane has to land with flaps is not true and to say no plane needs flaps is also not true. I think what Tevan says about how he uses flaps is spot on. Use them when you need them, that's what being a pilot is all about.

Chris

Shihtzutan

Corrections to spelling errors in my last post, sorry about that! I kind of left myself open with my full-scale experience didn't I? Tevans55 gets what I was saying and validated it at the same time. Flaps, add drag, it's also part of the landing checklist with full scale and it becomes a habit. Flaps are also used to steepen the approach; it's useful for clearing threshold obstacles such as power lines or trees. Soft field or short field landings are done with flaps. But with soft field lands we also add a little power for the softest of touchdowns; it's simply easier on the gear (the turf isn't always smooth). I didn't chime in because I needed to justify one's technique over another or to be confrontational with anyone. I just didn't think it was fair to make the statement of how important flaps were on a model airplane when in fact they are not. Wing loading and power to weight ratios are completely different on flying models. Flaps are fun; all my warbirds have them, but are they necessary? The answer is no. Do they add realism, . .ahh yes!

By the way, the Satio 1.50 fit perfectly. I needed to relocate the throttle cable and do some chin cowl rework. I went with the stock muffler and cocked header pipe kind of sideways so the muffler is mostly on the inside; it barely shows! Unfortunately I had to cut my scale exhaust; they are no longer functional. I decided it simply wasn't worth the mess it made. Clean up was a nightmare!

Johnnie Red

Hey Guys

Of course taking off or landing at grass fiels is totally different than taking off or landing in a paved runway. But generally speaking flaps are high lift devices that are dropping the stall speed to the minimum possible. They are changing the wing configuration by producing higher lift at lower speeds. That is the reason that a landing with flaps is giving you a perfect touchdown. The wheels and the retracts are touching down at lower speed. Flaps are changing the Clmax (Cl=lift coeficient).
We do not fly with computers so a flappless landing is always a riskier deal; to hurt your landing gear or your wingspars and wells..
If the above don't ring you a bell....Sorry guys but I fly this way and I smile when I see my (Big) old models at my hangar everyday.
While other people on my field that have the ideas of flappless landings are mouring and cursing on their (big) broken models.
My airplanes have countless takeoffs,landings and touch+go's (I fly regularely 2 to 3 days a week) so I assure you they are not Hangar-Queens! They are still surviving;and increasing in numbers because of the maintenance and the way that they are flown.

Because also I do not want to leave errors for my opinion with the word "Big" I mean models above 70 inches.

JR

tevans55

Venomous-
I am beginning to practice with my airbrush and I was wondering how you do the weathering near your wing roots that looks like the paint is worn off. Did you do that with an airbrush or did you use another method?

Chris Nicastro

My Feedback: (3)

Thats an easy one and you do it last once you airbrush your dirty details. Use a sponge and tamp the area with paint until you get the look your going for. Be sure to rotate the sponge to vary the edge detail and feather is out. I use Tamiya aluminum acrylic paint you can use what you like to get the effect of bare metal. Model Master Metalizer paints work very well too if you have them or know who sells them.

I did mine in layers thinking of how these wear areas happen in real life. The shinniest parts should be the spots with the most traffic.

Have fun with it and post some pics!

Chris

tevans55

Thanks V, I might give this a try. Gotta start practicing somewhere. I've tried some weathering on my B-25 but I want to keep trying new things and learn as much as I can. I really like what you did to your Spit.

phippsa3

What size wheels are you guys using on your Spits? Thanks.

Paps

Great Spit ! Gonna buy one as soon as i get some more money.
If you havent seen this yet check it our:
http://www.youtube.com/watch?v=MZglx...DEC3A&index=14

vasek

My Feedback: (4)

4"

tevans55

phippsa3-
I am using 4" Sullivan wheels with aluminum hubs. They look good, the price is right and they are extremely light.

Just got some video of my plane from one of the guys at my club.
http://www.youtube.com/watch?v=xpTW87KRNzc

Chris Nicastro

My Feedback: (3)

What engine are you flying in your Spit tevan?

tevans55

It's an OS 120 AX with a JTEC wrap around muffler.