By Neil Jones

The Tonny is a very useful 2m all round sailplane and comes in glider and electric versions.  It is manufactured by NAN Models in Bulgaria and comes highly pre-fabricated leaving the pilot little to do except install radio gear and fly. The Tonny and many other NAN models are imported into this country by Acemodel.
Acemodel’s proprieter is Austin Geurrier who is one of the UK’s leading F3j pilots. I must take my hat off to Austin, because he stocks an awful lot of planes. No more waiting for months on end, no more excuses for a lack of availability. Just send a cheque or use a credit card and a new model will be winging it’s way to you shortly. This is how buying a moulded plane should really be!

Why buy a Tonny?

When I was looking for a handy all purpose glider, I wanted something around the 2m mark. Big enough to soar, but small enough to throw around a bit and fly on smaller sites. Unfortunately for me, a lot of moulded 2m planes  seem very slope orientated. Having fast wing sections and being built quite heavily doesn’t bode too well for gentle thermal soaring on a calm summers evening. I  did want a model to slope soar with, but I also wanted something to practice and enjoy  proper thermal soaring with. I found the Tonny fitted the bill perfectly. I liked the choice of a modified SD7037 section (remember that one??). It appears to retain it’s 3 degrees or so of camber, but has been thinned  down a little bit for better penetration and faster flight. I also liked the fact it comes with flaps and ailerons, pretty essential for me, as it enables the pilot to really open up the flight  envelope and exploit CROW braking for precision landing in confined spaces. It also comes with a two-piece wing and two piece V-tail which means it breaks down nicely for transportation and storage.

I chose to have the glider version AND the electric version, both of which are the content of this review. Both have identical flying surfaces, but obviously differ in the fuselage. You could, if desired, purchase the glider version and simply buy an extra electric fuselage if you wanted to. All parts are moulded and jig drilled so are fully inter-changeable and swap over with ease.

So what do you get for your money?

Construction wise, the Tonny is pretty novel. The fuselages are conventional and very nicely moulded with a strong consistent seam that shouldn’t crack open at every little provocation. My glider version came with a sheath nose and a beautiful carbon/kevlar lay-up that was very strong and stiff. My electric version came with a canopy hatch and a plain glass lay-up with strip carbon reinforcement running full length. The electric version isn’t quite so stiff but has a larger diameter and is a fair bit lighter as you would expect for an electric version. Both have a good quality gel coat finish with little or no imperfections. The two-piece tails plug onto the fuselage via two 4mm carbon rods and two metal incidence pins. All holes come pre-drilled and both my Tonny’s had perfect V-tail alignment, although there was a bit of messing about with the incidence pins needed to seat the one tail half properly.
The wing seating area follows the lower contour of the modified SD7037 pretty well, and has an opening already cut for servo wiring and plugs. There are two holes already drilled for the wing bolts, and a piece of 4mm plywood epoxied in during manufacturer to reinforce the seam and bolt holes in this otherwise stressful area. The glider version comes with plastic snakes clothed in at regular intervals down the length of the boom during manufacture for security and slop free control. The snakes are left free after the wing seating area and need cutting and anchoring accordingly by the builder for his particular installation. The electric version comes without any control linkages. Instead, it has a cunning little carbon canopy on the underside of the tail mount in which you can mount two sub-micro servos to drive the elevators.

The wings and tail are both two piece. The main wing is held together with a  substantial  9mm round carbon joiner that has proven more than adequate in use. The construction of both the wings and tails is interesting. There is a pink foam core onto which the moulded glass/carbon laminate has been applied. Whether it has been vacuum bagged (unlikely) or moulded into place (more likely) I’m not so sure, but it gives the wings a very solid feel without excessive weight. There is carbon used in the D-box and main spars of the wings for good torsional and bending strength , and a very uniform and defect free paint/gelcoat surface finish to top things off. Where the wing is novel, is that NAN models have then removed a lot of the wing skin and pink foam material aft of the main spar and inserted balsa ribs with semi translucent Profilm/Oracover covering to form the remaining profile up to the false trailing edge. The flaps, ailerons, and false trailing edge remain moulded and ailerons and flaps are neatly skin hinged with Kevlar. Ailerons are top hinged and flaps are bottom hinged which is an ideal arrangement. No gap seals are present but then you wouldn’t necessarily expect them in a model of this price tag, nor are they going to make any real differences to performance either.
The wing is designed for 4 micro wing servos to drive each flap and aileron directly and there are nicely formed square apertures already cut  into the wing undersides at the appropriate locations. You can safely fit 13mm servos in the flap locations, but it is wise to go for something slightly thinner (12mm or less) for the ailerons. All wing wiring routing has been taken care of during manufacture thanks to drinking straws in place to take servo cables directly to servo locations.

Tailplanes are of a very similar construction method to the wing. Elevators are skin hinged on the top with Kevlar, and balsa ribs with Oracover/Profilm make up a large percentage of the symmetrical profile. Both the wing and tails are pretty stiff, despite the inclusion of a lot of fresh air. The wings are not as stiff as say a Graphite built up wing with carbon capped balsa  ribs but for it’s size, cost , and application the Tonny is plenty stiff enough.

Building the Glider fuselage

There are a few things to do, and they can be done in any order. I started with the tail seating arrangement. As supplied, the two 4mm carbon rods  come separately. My choice was to epoxy them firmly into the holes already formed in the fuselage as is conventionally done after thoroughly checking side to side and fore and aft alignment was okay. One rod needs to have  a few millimetres taken off it as one hole is slightly deeper than the other. With this done, epoxy the rods in place and wipe any excess squeegied out immediately to ensure the tails sit right up to the tail seating cheeks. When done, turn your attention to the incidence pegs. On both the glider and electric version, I found one incidence peg hole was slightly out. Incidence wise it was perfect, but it was a millimeter or so out horizontally. I could have bent the peg or filed the hole, but instead I used cyano and micro-balloons to fill in the original hole and then re-drilled accordingly.
You will need to form your own V-tail linkages. I chose to use piano wire with Kavan 2mm ball links soldered onto the ends. Just ensure to form a 10mm or 15mm long 90 degree bend at the end of each linkage  to bite and grip into the elevators to drive them up and down securely. To make thing neater, after drilling a 1.5mm hole carefully into each elevator root to accommodate the 90 degree bend, I used a small piece of a broken needle file in the drill to file a perfectly recessed slot along the length of the elevator root. This slot then accommodated the piano wire linkage beautifully and made the whole lot very secure once epoxied into place.

I then turned my attention to the other end of the linkage. I used Multiplex MS-X3’s for the tail and had to cut my own slots in the fuselage inner nose to accept them. Micro servos of 13mm -15mm are ideal for the Tonny tail and are cheap and plentiful these days. Once the slots were cut, I epoxied spruce servo rails in underneath to take the servo screws as the fibre glass there already  isn’t thick enough to take screws with any authority.
Once the servos were in place, I screwed on the horns and marked their height and position on the bulkhead. When happy, I took the servos back out and drilled two 3mm holes at each mark to take the snakes. Having pulled out the metal piano wire inners, I carefully pulled each snake down and through each hole taking great care not to crease them. Creasing can lead to stiff  linkages and poor centering so be careful! Once in place it was a simple job to epoxy them in place and cut them to length.
Having used threaded 2mm quicklink  adaptors and threaded plastic ball joints on the tail end it gave me plenty of adjustment so I used Z-bends at the servo end for simplicity.

For wing mounting, I chose M5 bolts as these seemed  an ideal fit to the pre-drilled holes in the wing and fuselage holes. I used a pair of flanged 5mm captive nuts with the barbs cut down to half  length  to give a very solid and reliable mount for the wing. After checking everything was aligned and the wing jigged correctly onto the fuselage (needed a little opening out of the pre-drilled fuselage holes) I offered up the captive nuts to the underside of the plywood plate.  To pull them hard up into the ply plate I made up a thick carbon sheet with two 5mm holes drilled into it. This was laid over the wing mounting holes and the M5 screws carefully threaded into the captive nuts. I kept turning until the screw heads hit the carbon plate and then really started to tighten them up hard in order to draw the captive nuts and their barbs up  into the ply plate.  This really did the trick and just a small application of cyano and micro balloons kept it all locked solidly in place. At the front, the wing is mounted via two large diameter metal pins that lock into the front bulkhead. On my glider version, these holes needed opening out quite significantly with a needle file to get the correct fit. On the electric version it came already done and neater and better than I managed to do it. Bear in mind that if you do have to go the needle file route, keep a regular check on the fit. Open the holes out too much and you will have sloppy fitting wings!

You may find the nose cone comes with a sloppy fit. Mine did. To rectify this either place a small blob of epoxy or cyano and micro balloons on the top and bottom inside surfaces of the nose cone and sand or file as appropriate to get a nice snug fit. Alternatively, laminate a single layer of thin glass cloth around the inside perimeter of the nose cone to make it a nice tight fit on the fuselage inner.

The inner frontal nose cut out comes already done for you, and I chose to make up a 4-cell GP 1100mah Ni-Mh receiver pack to power the 6 servos with adequate oomph. A large (ish) Multiplex 9-ch IPD receiver just squeezed in  and overall the glider version fuselage is slim, nicely proportioned, strong, and very pretty indeed.

Building the Electric fuselage

Work surrounding the wing mounting is identical to that of the glider version. There are variations in the canopy, the tail servos, and the motor and battery mounting however.

I started with the motor mount. The Tonny comes with a pre-fabricated 3mm thick GRP disc that needs to be firmly epoxied to the inside of the front bulkhead. You first need to choose your power plant, and I chose the recommended Model Motors Axi 2820/10 out runner. There is up to 36mm diameter available in the Tonny fuselage so an out runner is cheap and easily fitted. There is also room for an inrunner motor and gearbox combo as well such as  those available from Kontronic or Hacker but these are a lot more expensive and not  strictly necessary in the Tonny unless you are into electric competition.
The central hole in the GRP disc fitted the 2820/10 perfectly, so it was epoxied into the front of the fuselage hard up against the front bulkead with 24 hour laminating resin and lots of micro balloons. When fully cured, I stuck the supplied Model Motors mounting sticker accurately onto the front bulkead to give me screw hole and cooling hole positions. A small amount of down thrust has been moulded into the fuselage already, so all you need to take care of is accurate positioning of the screw holes to make sure the spinner lines up nicely with the bulkhead and that your cooling slots match the motors.

I then used a long bit of piano wire epoxied in the middle to hold the canopy into position. This is a neat internal way of doing it which I borrowed from Samba Models on their  Pike Superior. Lots of similar models use the same principle, and if done correctly it works very well indeed.

Most of the work on the electric version surrounds the tail. I have seen installations on the Internet where the servos are installed on rails underneath the wing. Snake linkages have then been added down the boom and anchored underneath the tailplanes. The snakes then protrude outside the fuselage and link up externally with the elevator linkages. In order to achieve this however, the elevator linkages have to be  bent outwards quite considerably to allow an external connection  of the control surfaces. The nicely made carbon hatch has then only been utilised to make locating and gluing the snakes into place much easier. This is undoubtedly the simplest way of doing things. If you want to get into the air quickly at all costs then go down this route by all means. To me however, it is an inappropriate way of doing it.
I’m confident  the hatch is there so that you can install two sub micro servos into the tailplane area and allow all the linkages and connections to be invisible and completely internal. There is more work to be done, but this is the route I chose to go down.
I started by making up a small servo tray out of thin carbon sheet. The servos I used are Supertec Digital Titch 50’s and these appealed because they are absolutely tiny and weigh only 8g each. They are also digital, have 1kg of pull, are fast, and have a relatively large metal output gear. They are also very good value for money at only around £15 each!
The holes for the tailplane joiners are reinforced with a lot of glass and carbon and form their own bulkead in the tail recess. I placed one servo in front of this bulkhead, and one servo behind.
Because I still wanted to have removeable tailplanes and a completely internal linkage system, a lot of thought and trial went into how best to go about it. In the end the two 4mm carbon rods were epoxied into each tailplane half instead of into the fuselage (one rod still needed a few millimetres taken off it as with the glider version). This was to give the tailplanes more freedom of movement and angulation to accommodate the elevator linkages when being pushed into place. As small a hole as possible was drilled and filed  into the fuselage at each elevator linkage possible to allow easy installation, removal, and freedom of control movement.
I then made up and installed the piano wire elevator linkages in exactly the same manner as for the glider version, except bent them and placed an emphasis on making sure they met as close together as possible and as centrally as possible within the confines of the fuselage. It’s tight in there!

I used a glass fibre reinforced plastic R/C car body post to keep the hatch on. I drilled a hole in the carbon servo tray by the bulkhead and epoxied in the body mount. Anyone who has had an R/C car will know these body posts come with a series of small holes to take a body pin/’R’ clip with which to keep the body shell in place but allow easy removal when needed. The body post was trimmed down in length accordingly and a hole drilled in the carbon servo hatch. The servo hatch is now very securely attached with a body pin, yet easily removeable, and it saves forgetting and/or playing around with pieces of tape when you pop out for a cheeky fly on your way home from work! It’s also much neater in my opinion and sits no more than 1mm proud of the hatch.
I also elected to make the tailplanes bolt-on for a similar reason. This was achieved by epoxying  a metal thread into the root of each tailplane half (I used the M3 barrel off one of those threaded metal control horns).  I then drilled a hole at the appropriate points in the  fuselage, and used short M3 allen bolts from inside to keep the tails in place.

Final job is to arrange a suitable battery mount. I used a 2mm carbon plate epoxied into the fuselage at a position suitable  to obtain the correct CG. An 8-cell GP2200 pack was chosen to power the Model Motors Axi 2820/10 on a Graupner carbon 12 x 7 folding prop. I decided to hold the battery in place longitudinally by a length of Velcro along the length of the carbon plate. To hold it in place vertically, I drilled and filed two narrow slots either side of the battery pack and threaded through Velcro to make a strap that keeps the 380g battery pack firmly in place when given some vertical ‘g’.

Building the wings

Thankfully, much of the work has already been done for you. Twisted 3-core servo cabling is better for rejecting interference and pushing up the drinking straws, so use this if you can. On the glider version I filed out a recess in the wing root to glue the servo plugs directly into place and wished I hadn’t bothered. On the electric version then, I left the servo plugs dangling free. Both ways achieve the same thing so do whichever way you think best.

Next thing I did was to arrange for the control linkages and control horns. When you hold the wing up to the light, you will notice 1 round dark patch on each aileron and flap. This is where the manufacturers have added some hard epoxy/microballon type material to give a secure foundation for the control horns. Drill or file your opening for the control horns here. I chose M3 threaded brass control horns available from Cubitts models but you could easily make up suitable horns from carbon or GRP sheet.
I elected to drive the flaps from the top as they are bottom hinged. This is the correct way of doing it and gives the best mechanical set up with very little slop. It means you will have to file a slot on the upper wing surfaces to allow room for the linkage and quicklink. You will also have to file a slot in the false trailing edges and pink foam cores as well. If you make sure you rake the angle of your control horn forward, you will be rewarded with a slop free and mechanically sound flap linkage that can give you as much CROW flap as you’ll ever need. I decided to cut down a pair of the supplied servo covers to cover up the linkages on the top surfaces. The holes in the wing where the flap servos go were covered up with thin white plasticard.

When it comes to installing the servos, carefully scrape out the remaining layer of pink foam with a blunt flat headed screwdriver or fingernails. Carefully keep scraping until you see the carbon skin coming through and then roughen it up with rough sandpaper and epoxy your servos in place, having first sorted out all your neutrals and control movements. Cut and apply servo covers and the wing is ready to go.

My overall impressions so far are very favourable and the quality is good. For the price tag the quality and attention to detail will be almost impossible to beat. Main likes at the moment are the excellent lay-up of the fuselages and the general layout of the design.
As with all moulded models, exercise great care when assembling and working on the plane in the workshop otherwise dings and dents can easily happen. Take extra care with the Tonny however, because of the Profilm/Oracover finish that can all too easily puncture and lift with screwdrivers and soldering irons hanging around!
How will they fly?? See page 2