Basic building tips

Model by model, we're going to offer some build tips to help out where the instructions fall short or where we feel there's scope for drama avoidance. We see a lot of different interpretations of kit assembly, from the occasional lack of loctite across the spectrum to extraordinary imagination. We love this hobby but its also a pretty uncompromising sport; these are complex machines with little margin for error, both in terms of flying and mechanical integrity. Failures will not only be costly, but could also cause injury and for this reason its important to adopt the right approach to building and maintaining.

Some General Principles

Tightening screws. Be aware of materials, sizes and driver size. A 2mm set screw with a 1.5 mm Allen drive going into steel does not require the same torque as a 4mm engine mounting bolt. Over tightening will not reduce the chance of loosening in flight. A small dab of blue thread lock applied to clean surfaces will. Over tightening and securing with red thread lock will definitely ensure that you will then need a new Allen driver when the inevitable time arrives to remove it (purely in the interest of maintenance of course..)

Sounds daft, but don't cross thread a bolt. Threaded steel into any threaded metal should be smooth. If its tight, or stiff, stop and check it. It should be square into the thread, carefully remove, if you have a tap and dye set, clean the threads up and start again. Then remember to insert bolts squarely into surfaces. Then it won't happen again.

You are not looking to distort materials when tightening bolts. Over tightening not only reduces the chances of successful removal but it will also stretch the material of either the bolt or the surface of the thread. This in turn will dramatically increase the likelihood of failure. For example consider the role of the 'Jesus' bolt holding the head assembly to the mainshaft: OK, I can understand the logic which says 'better make sure this is tight, don't want that one to work loose!' fair enough, but what are the forces acting on it? Rotational and longitudinal, naturally we don't want it to allow any slop, but over tightening this bolt will stretch and weaken it. Normally its retained by a Nyloc nut, these are good things and resist loosening extremely effectively. However, once they've been on and off a few times they become less effective, they cost peanuts, just replace it.

OK, so I built my heli before I read this and I want to undo a set screw, bolt etc that doesn't want to play. First things first, DON'T keep trying until you wear out the hex drive. You will need this or you will have to skip to the 'very advanced rescue' section. Heat is the first option, this is very good with steel bolts into aluminium (aluminium expands faster than steel) but is still effective steel to steel as it will reduce the impact of thread lock. An oven works fine, but try a hair drier first, sometimes just gentle heat is enough to break the bond, but do not apply too much torque, strip that driver and your day just took a major hit. If its still not moving, apply more heat. Love that driver, its your friend.

Bolts into plastic. Truly a bastardisation of the fine art of engineering. Still its a fact of life, the concept of a finely cut metric thread tearing its way through a smooth plastic bore is shocking but a commercial necessity. So use compassion, when it starts to tighten up, give it a nip and leave it. Essentially, such advanced engineering will not be used in critical areas, so strength is probably not too important. The thing to bear in mind is to be doubly careful the second time you have to insert the bolt, and trebly careful the third time etc...

Self tapping screws into plastic, a little more acceptable but still invokes memories of some third rate Discovery channel DIY show. Just be careful. A cunning Japanese invention we didn't know we needed until we discovered we didn't want it but by that time it was too late.

Instruction Manuals

Read them. Read again. Before you start building, get a flavour for how the model goes together and works. Check out the icons, most of them have a symbol for oil, grease and THREAD LOCK. Obey them, if you're not sure about something give us a call, we've normally built at least one of everything we sell and this is what we're here for. Except for German speed controller manuals, throw them away and ask a mate who's got one. Never buy a German brushless speed controller if you haven't got a mate who's got one. If you haven't got a mate call us.

The Raptor....

We've sold a lot of replacement blades to people who haven't managed to get their raptor into the air. Tip; the plastic covering on the blades is supposed to be there - leave it on, this is part of the blade construction and prevents the ingress of moisture. Remove a part around the root for gluing (epoxy) the plastic root reinforcement strips.

Ball links, the balls are not supposed to swivel on their mountings, the plastic ball link should swivel on the steel ball, so make sure these are tight, they are part of your control system.

If this is your first helicopter, get an experienced flier to check it over (if you can get to us, even better) this is time well spent, it takes a while to get into the groove of what to look for. A minor defect can result in an instant rebuild at best and injury at worst.