There are many options for acquiring your first model, all with their own advantages and disadvantages;
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There are hundreds of plans available, for practically any sort of model. You can buy them from specialist publishers such as Nexus, who have a catalogue of designs from many different designers; from individual designers who specialise in one type of model, such as scale; and many modelling magazines publish free plans, complete with a guide to construction. Many people like this start-to-finish approach but it does require a higher degree of constructional skill. Beginners are also less likely to have wood or accessories already to hand and will have to buy everything needed: these items may be specified on the plan but if not then you will have to choose and source all the necessary parts yourself.
One step up from a plan is a semi-kit; that is a plan plus some of the parts required to build it. Usually it includes moulded and plywood components, but you are left to buy the remainder of the wood and parts required to complete the model. The advantages are that you are then free to use the materials and hardware, hinges, engine mounts and so on, of your choice. For experienced modellers this can be a cost saving as they have probably built up a stock of components from other projects, as well as leaving them free to use their judgement on their preferred type or brand of equipment; the beginner will of course have to buy everything new.
The Kit option provides you with practically everything you need to complete a model. Often the only thing not provided is the covering material, and sometimes even that is included. The advantages for a beginner are that there is little else to buy, and the kit manufacturer will have ensured that the hardware provided is suitable for the model. The amount of building required can vary immensely; model designs range from traditional balsa based model construction which can require many hours to complete, to models with foam cored wings and glass-fibre moulded fuselages which can be completed in a few evenings work. Each style has it’s advantages in construction and repair requirements and the choice is down to your personal preference
ARTF (Almost Ready To Fly) means that the majority of the construction and covering has been completed by the manufacturer, and all you have to do is final assembly of the major parts: perhaps joining the wings and fitting the tailplane. You will still have to install the R/C equipment and the engine, if that has not been included. ARTF models are a very fast and successful method of getting into the air, with most of the work done for you by the manufacturer, but consequently they are the most expensive way to do it.
The range of models available is huge, from simple trainers to sophisticated scale aerobatic types. If you buy ARTF, look for the availability of spare parts, sometimes the construction methods do mot lend themselves to home repair and you may find yourself needing to buy a new wing or other part.
Buying a used model is probably the quickest and cheapest way of getting started, but as for the purchase of any second-hand item, there are pitfalls. Trainers, by their very nature, lead a hard life and any prospective purchase will need to be inspected very carefully. The best course of action is to ask a trusted and experienced club-mate to examine the model for you. You can often pick up a good deal for a model and engine combination, and sometimes even the radio equipment if the seller is upgrading to a more sophisticated set.
The advantage to this is that all installation problems will have been dealt with, and the model should be flight proven and trimmed. You need to look out for repairs - if these have been done properly then there should be no problem, but repairs are an indication of a crash and there could be other, undiscovered problems besides the repaired ones.