There are a lot of robots here that have been 3D printed. The 3D printing process builds one layer at a time, which is visible. There are multiple ways to handle removing this, but it isn't normally necessary.

The Infill of a 3D printed part helps to determine how strong it is. Some people print gears and such with 100% infill, which makes them quite strong.

The amount of flex that an object has is determined by the filament that is used. There are some very flexible filaments (used for joints in fingers or treads on a track or tire on a wheel for example) and there are filaments that have metal particles in them. It is really up to what you want to use.

As far as smoothing a 3D printed object, most will use sandpaper if the part needs to be smoother. Some will fill and paint parts also. Some filaments are able to be polished using Acetone and other chemicals.

I do recommend using a 3D printer for robot parts. There are other options like making molds and casting parts. A 3D printer can be used to make your blank which then can have a mold made from it. Depending on how smooth your 3D printed part is will determine how smooth your mold is. This gets expensive up front but allows you to duplicate parts quickly (in an hour or so as opposed to multiple hours). Most people don't go to this route simply due to the upfront cost and skill in making molds that is needed, but it is an option.

I hope this helps. If you decide to go the 3D printing route, there are a ton of various options. Which printer, which slicer software and so on. After a while, you will want to start building your own parts from your own designs probably. This then gets into deciding on which CAD program or 3D modeling program to use. It is a world on its own, but lucky for you, you would be getting into it when there are a ton of really good options available instead of sourcing and building something from scratch.

Thanks for the reply!

Seems like sanding and acetone treating ABS might get a pretty professional looking result.

Will prolly get the following printer:

https://www.monoprice.com/product?p_id=13860

Use ABS and use acetone to vapor smooth the print... Welcome to modern technology man... 3D printing is simply awesome for creating just about anything you want...

For me there was no robotics before 3D printing. Everything is possible with it just about. I made a plexiglass rover back in the early college days. Today there are so many tools available for low cost. We are practically in a think it make it world now.

I could never make this with Plexi

A 3D printer would be simply amazing right now...i know for my next personal project i could really do with one..last night would have been fantastic btw..my poor dremel.

The robots you all create with 3d printers are just amazing.

Really looking forward to finding my first 3D printer.

my son has that printer. He likes it. He has only printed PLA with it. I havent seen it personally. If you are planning on printing ABS I cant speak to how it does. For ABS, make sure it has a heated bed. It looks like it does. You may want to place a box over the printer when printing ABS to help control the environment.

Yea, I read that the printer doesn't do ABS well after I bought it and panicked, but it looks like with some slight alterations to the default print set-up ABS should print well enough.

I read a ton of bad reviews about my printer. I have come to the conclusion that a lot of people buy printers, get in over their head then complain about them on the internet. I think you will be fine.