Where to start ?
Most people will tell you to head over to the official R2 Builders club (https://astromech.net/) which has lots of information on building your own full size R2. They have been around for years and its free to join. However I would advise that you look at youtube first to get a better idea of whats involved and then look at the astromech forums.
If you want to build a metal R2 then it wont be cheap. Many builders will easily spend over $10,000 on metal parts and electronics, spread over many years. You can find help with getting metal parts and components on the astromech site. But you will need to hunt around for someone who can help. The cheapest I found a metal dome in stock for was £600 plus postage to the UK from the US. And that was just for an uncut aluminum one, like the one in the photo. That said I have seen them for around £380 mark + postage, but they are rarely in stock at those prices (Granite Earth) Metal ones are the best looking and will last the longest but their are other options, that are cheaper, though still require a lot of work.
3D printing has lowered the cost of building and owning your own astromech, thanks to one man, Mr Baddeley.
Mr Baddeley design a 3D printed, full size, working replicator of R2 and made the print file available for free online. To find out more or download the files to print off yourself, visit these sites
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