Modeltech introduces the the Magic Formula 3D to its line of 3D type aircraft. It includes large control surfaces and expertly covered in genuine Monokote.

Kit Name: Magic Modeltech Formula 3d
Price: $179.99 retail price
Wingspan: 60 "
Wing Area: 1027 sq. in.
Flying Weight as tested: 104oz.
Motor: Magnum XL 70 RFS 4 Stroke
Radio equipment: Futaba 14MZ

Items needed to complete:

• Square
• Hobby Knife
• Ruler
• Screwdrivers
• Drill bits
• Covering iron
• 5 and 30 minute epoxy
• Silicon glue
• Thin and thick CA
• Sanding blocks

To use these smaller servos I had to add a hardwood block to the servo opening to make them fit. This only took a few minutes to do with some thin and thick CA. They include some sort of cloth string to pull the servo wires thru the wing, its not pretty but it seemed to work just fine.

They even had rolled paper tubes inside the wing for the servo wire, they had Oriental writing all over them and looked like they were from a magazine. You can see them thru the top of the wing.

Extension tied to the included string.

Servo wire opening at root.

Servo installed.

I always use shrink tubing to secure my servo extensions but you could also use a piece of dental floss tied around them from end to end. I cut the covering away from the servo opening in the root of the wing and then mounted the servo in the opening.

The next step was joining the wing halves.

First I removed the little bit of covering overhanging the root rib to ensure a good wood to wood bond, I then made a line on the center of the wing joiner. It is perfectly straight so it doesn't matter which direction it is installed as there is no dihedral in the wing when completed. I put the wing together to check the fit and there were some small gaps when pushed together at the root ribs but a little sanding took care of them in no time. Per the manual I glued the joiner into one wing half with 30 minute epoxy. Be sure not to use 5 minute as it is not strong enough.

After it was dry I proceeded to glue the other wing half, making sure to cover both root ribs and the joiner/joiner socket very well with 30 minute epoxy and left it to dry overnight. They have a wooden dowel in one of the wings to make sure the alignment is correct, nice touch!

The wing was glued with 30 minute epoxy and left to dry overnight. The next part to install was the wing bolt reinforcement piece and the belly pan. The manual said to cut the rear part of the belly pan so if your screws dropped in there you could remove them. It is lined up on the bottom of the wing with it bolted in place. Make sure you have a large enough gap at the front of it so you can remove the wing, I had to sand mine as it was too tight. The belly pan is then glued on with clear silicone. You can use shoo goo or epoxy if you want but the recommended silicone works really well, you just have to wait longer for it to dry.

I hinged the ailerons next, they are single beveled which seemed a little unusual for CA hinges as they needed to be at the top of the bevel and bent a little bit when going into the aileron. after hinging them I sealed the surface gap with some clear Monokote.

The included hardware for the aileron linkages was not useable. The pushrods were too long after the clevis was even threaded on as much as it could go. I replaced them with 2-56 pushrods with a threaded clevis on one end and a solder clevis on the other end.

The rudder pull-pull setup worked very well. The clevis had to be threaded on pretty far to get the distance correct as seen in the picture. I also used a zip tie to secure it from coming off as they are rather large, a piece of fuel tubing would break in no time.

I next installed the landing gear and tail skid. The skid is held on with a couple nylon straps, I would have liked a tailwheel instead as skids usually wear out when flying from a paved runway.

The main gear was bolted to the fuse making sure to use Loctite.

The plastic wheelpants were cut out with a sharp hobby knife. The wheels were slid on the axle bolt and the nylon spacer was used on the side of the wheel that allowed it to stick out the most as seen in the picture.

The wheel is then put thru the wheelpant and then into the main gear which holds the pant on when you tighten the 2 locknuts sandwiching the gear and pant in between.. I had to fool with this for half an hour to get mine mounted as when I tightened the nut holding the axle to the gear, the other locknut on the axle would turn pushing the wheel against the wheelpant and not allowing it to turn. To tighten it I had to drill a small hole on the outside of the pant so I could use a Phillips head screwdriver on the screw to keep it from turning. A small screw was then used to hold the pant from turning, but it just went into thin plastic so I also added some shoo goo to it.

Engine installation was next. For the Formula 3d I used the recommended engine, a Magnum XL .70RFS 4 stroke engine and a 13x6 prop. The engine mount was bolted on to the firewall that already had the blind nuts installed. I used Loctite to make sure they would not come out. It is a nice touch when they are already mounted and all you have to do is bolt them up, no drilling and figuring out where they need to go.

The engine was mounted on the rails so the backplate was 4 1/2" from the firewall as stated in the manual so the spinner to cowl gap is perfect.. I had to grind on the front rails a bit to get the cowl fit, they also mention this.

I could not get the included throttle linkage to work very well. They have you bend a u shape into the pushrod, then inside of the fuse it is supposed to bend around the fuel tank. I used a Dubro 4 stroke linkage and a throttle cable instead and it worked perfectly. I used a micro servo for the throttle to save weight.

They include a plastic spinner which took a lot of cutting to get it fitting properly, the little tabs in the backplate needed to be removed so the prop could orientate the right direction for the spinner to fit. I really don't like using plastic spinners on a 4 stroke because they will break if the engine ever backfires or kicks hard.

The fuel tank is a 2 line tank and was stuck into the front of the fuse with some foam to hold it in place. As you can see in the pictures I just ran the fuel line out of the cowl to a filter, just unplug it to fuel it up then plug it back in.

I could not fit everything inside of the fuse since the rudder and throttle servo took up most of the room. I removed some covering behind the wing area and put my receiver in there, covering it up with some matching Monokote afterwards. The receiver battery went on a tray I made over the pull pull rods for the rudder and it was a tight fit..

The front of the fuse is not rounded perfectly so the canopy does not fit tight against it. I glued mine on after cutting it out with pacer canopy glue. I then took some black trim tape and went around it so you can't see the gaps and to keep air from entering and trying to blow the canopy off. My canopy was a little deformed as it is made out of really thin plastic.

I checked the balance of the Formula and it was right at 4 1/2" back from the leading edge which the manual says to test fly the model at.

I setup the control throws per the manual for test flying then went to the field. Here are the rates they give.

• 1 1/4" up and down ailerons
• 1 1/2" up and down elevator
• 1 5/8" right and left rudder

They also give a sport flying rate and a 3D rate.

Sport flying rates

• 1 3/4" Up and down ailerons
• 1 3/4" Up and down elevator
• 2" right and left rudder

3D Rates

• 2 3/8" Up and down ailerons
• 3 7/8" Up and down elevator
• as much possible rudder

The first flights resulted in the plastic spinner breaking off as the engine backfired when trying to start it so I flew without a spinner as you can see. Takeoff roll was very short and it only required about 3 clicks to trim it out. It tracked straight down the runway with a tiny bit of rudder input. After a few circuits I tested the aerobatic ability of the Formula. The recommended CG seemed to be about perfect as inverted only required a touch of down elevator to keep it flying level. The engine was still set very rich so I had a few deadstick landings which were no problem for the Formula as it just floats in. I was using a Master Airscrew 13x6 prop.

The Formula floats like a funfly airplane should and here is a list of how it performs.

• Inverted flight required a touch of down elevator with the recommended CG setting which is perfect.
• Knife edge flight had some minor coupling towards the canopy but you can hold it out with elevator or if you have a computer radio mix it out.
• Hovering required almost full throttle so there is no punch out from a hover. The APC prop was a little better than the Master Airscrew.
• Harriers had a lot of wing rock and were hard to control as my model wanted to snap out of them. Aileron mixing helped a bit but it still would snap out easily.
• Knife edge spins were awesome with some spoileron mixing, you can get it to spin likes its hanging from the wingtip by a string.
• Blenders were very good and it will transition to a very flat inverted spin.
• Waterfalls were also good with the spoilerons mixed it, you can flip it around the CG.
• Inside and outside loops were no problem for the Formula 3D
• Aileron rolls were very fast on high rates, be sure to use some expo on them. I used about 60% but that is just my personal preference.
• Snaps were clean with no tendency to over snap, it stopped when you let go of the stick.
• Torque rolls were easily done and it likes to spin pretty fast.
• Spins were easily done both upright and inverted.
• Loops and rolls were not a problem, both inside and outside.

Click Here to See the Formula 3D in action!
6.47 MB

A week later I took the Formula out again and leaned out the engine some more. I upgraded to a Great Planes aluminum spinner and a APC 13x6 prop, this combination was better as there was no chance of breaking the spinner. The formula took off with ease and the APC prop worked better than the Master Aircrew for hovering and general "thrust" maneuvers. The included fuel tank gives about 10-12 minute flights depending on how much full throttle is used.

The Formula and Magnum engine are a great match. It will be a great addition to your aerobatic fleet and would make a perfect introduction to the 3d world.

Modeltech
Distributed by:



Global Hobby Distributors
18480 Bandilier Circle
Fountain Valley, CA 92708
Phone: (714) 963-0133
www.globalhobby.com

Magnum Engines
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Hobby People
Sales Phone:1-800-854-8471
http://hobbypeople.net
service@hobbypeople.net