SLOPING OFF...
...the Newsletter of Christchurch and District Model Flying Club for March 2021
Flite Test Fokker Triplane DR1
by Martin Delaney
Flite Test was created by a group of friends in the USA who are passionate about rc flying and having fun. They came up with a host of designs that could be made cheaply out of foamboard and low cost radio gear and have since evolved into quite a big presence in the entry level/fun fly side of rc modelling.
I was keen to try building something out of foamboard or depron as it looked cheap, quick and relatively easy and when I saw the FT DR1 it looked perfect. Free plans are available in A4 tiled format so you can print them out on a home printer and then just tape together. All you need tool wise is a hot glue gun and a sharp craft knife or scalpel(well almost!).
I read a few of the the rcgroup forums about foamboard building and discovered there appears to be two types of foamboard(fb) out there. Most fb, like that sold in Hobbycraft, is about 50% heavier than the Flite Test Maker fb so it’s worth getting the right stuff. A google search will generate a few sources, however most sellers require a minimum order of 5 sheets(about £25). One sheet is enough for this model.
By far the most time consuming bit is cutting out the parts which can be a little fiddly and requires a sharp, preferably new, scalpel blade. I should say at this point you can buy the kit online for about £30 which has laser cut parts and the extra bits of hardware you need but I really wanted the satisfaction of building from scratch and keeping it as cheap as possible. Once you’ve cut the parts out, there is a full build video on youtube to guide you through the whole process. Its quick and fun as the hot glue sets in about a minute so it all comes together very quickly. I didn’t feel my parts were particularly accurately cut out but it still all fitted together quite well with a little trimming and sanding.
Note - this picture is courtesy of FT build instructions – my cut out parts were, how shall I say, not quite as neat!
You will need a few other bits to finish the model – a small piece of 3-4mm ply for a firewall, some piano wire for pushrods and u/c ,some wheels and surface control horns, an A4 sheet of posterboard and some BBQ skewers but that’s about it and probably what you have lying around already – if not just give me shout. I had a lot of fun building it and then popped down the local discount hardware store for some cheap spray paint and gave it a coat or two.
Radio wise you need a couple of 6-9g servos. Its very difficult to change servos once built (but possible, just) so worth making sure they work ok. Recommended motor is a 2204/5 2400kv, 20amp esc, 6X4.5 prop and an 800mah 3s battery. I used what I had lying around – a little 1500kv ‘blue wonder’ motor, 7X3.8 prop, 12A esc and a 500mah battery and it flies fine but I do think it would benefit from a smaller prop/higher kv set up as per the recommendations. There seems to be plenty of very cheap drone motors out there fitting this spec.
And so, all built and set up I headed off to Oldfield to see if it would fly. I thought I’d go for a nice progressive power take off which was a mistake. It’s virtually uncontrollable on the ground so recommended take off technique is point into wind and gun it! As soon as you’re airborne throttle back if your motor has plenty of power and you’ve gained some height try and trim it out. Mine flew pretty well set up with full recommended control throws and 30% expo but I won’t deny it’s a little twitchy and flies best with good throttle management. It will fly very slowly and I find this most entertaining a few feet off the ground. It will do some fun aerobatics like loops, barrel rolls and stall turns but will try and roll out due to all the dihedral but it is generally very entertaining to fly. Except if you close the throttle completely in which case it literally falls out of the sky!
