I have a friend who avidly collects military memorabilia. In particular he covets a cap badge from a local long disbanded regiment. Originals are v rare and out of his financial reach.
If he could borrow one, what is the process for replicating one? I assume there is a 3D scanner and the once that data has been recorded then it will need a 3D printer? As its for display only then the material is not an issue as if he used plastic then he feels he couldnt be accused of forging or ‘copying’ and replicating for gain.

Is it possible to create a 3D replica using photographs? Im just trying to assess what he will need to do to get a replica made.

the first and most important question is what does this friend think is expensive? how much is this badge? if its only a few hundred quid just go and buy it

On speaking with him, it appears the problem is actually finding one to buy. He may be able to borrow one from a local collection

I did this on some bones for my final year project.

Used a CT scanner 3d modelling software and a 3d scanner.

It was kit running into the millions back in 2007

It’s quite a lot of work to produce the cad files that would be needed for a 3d printer or cnc machine. If you use a laser scanner, the scanning process is actually pretty quick, depending on the intricacies of the scanned component. But cleaning up the point cloud to produce a decent stl file to covert to CAD data is quite a long process.
The issue would be finding somewhere/someone with the right equipment and who can then process the cad data.
If there are any composite companies near you, it could be worth contacting them as they may have a faro or romer arm with laser scanner and the staff to use it.

It may be easier to cast a mould (possibly silicon or epoxy putty depending on the shape) off an original and then cast the replica, if someone were willing to let you do that off their original.

I was going to say a mould might be easier. ‘proper’ 3d scanning kit can get pretty expensive, although you could try photogrammetry.

As mentioned above, its often the intermediate stage between scanning and printing that everyone forgets about but which actually takes the time.

If there aren’t too many undercuts, as swannay says, mould one. Can be as simple as some modelling clay and epoxy resin.

There is a (relatively) low cost solution, a Roland MDX mill with mechanical scanner. It basically “probes” whatever it’s scanning by repeatedly prodding it, then can mill a replica out of aluminium or resin (or could mill a mould). Very common machines, a lot of schools/colleges have one, might be worth contacting some to see if anyone would do the job after hours or as a project with students. This sort of 2.5d job is ideal for such a system. Roland also make a low-cost laser scanner (Picza) but they are rare.

Alternatively as the design is probably quite basic (as most cap badges are) any decent modeller should be able to knock up a file from a straight on photo (not saying this wouldn’t take some time) as it’s basically just a 2d image extruded to give it a bit of depth. Then get someone to mill or 3D print the file.