Subtractive Manufacturing vs Additive Manufacturing


A number of my viewers have asked for a channel on this forum about CNC and Milling. I made this new channel a bit more generic and called it Subtractive Manufacturing.

In 3d printing, we create objects by adding material layer by layer. The material may be plastic in the case of FDM 3d printers that print from plastic filaments. It might be metal, concrete, or even pancake batter.

Prior to the development of additive manufacturing based 3d printing, subtractive manufacturing and molding dominated. In subtractive manufacturing, a device, which could be a tool or a laser, cuts away material from a block to form an object. In molding, the material is poured into a mold, that is often made with a subtractive process, to create an object. Injection molding is an example of high volume and low-cost molding.

In addition to additive and subtractive processes, assemblies are often created from these parts. For example, a house is sometimes built from wood, that was cut (subtracted or milled) from a tree or bricks that are molded. Today’s vehicles are assembled from parts that are produced with CNC or Milling Machines, molding with Injection molders and printed on 3d printers.

The revolution in manufacturing is that these technologies are now available at relatively low costs (yes a good laser is still out of my price range) and available to many hobbyists. This enables thousands if not millions of people to become “makers”, creators of new things assisted by this technology revolution.

The DrVAX community is all about this revolution.


…and as the manufacturing technology evolves, many of us makers can combine FFF or SLA (additive manufacturing) with CNC machining ( subtractive manufacturing ) to complete in accuracy and smoothness a complicated object. Possibilities? Limitless!!! Just think of this: You’d like to have a shiny or smooth surface on your object/model clean and sharp. CNC is the next step. There is a small restrition on machining materials: You can’t mill softa materials like rubber ( TPU,TPE,TPC ) because of its softness and this is acceptable. The rest of materials ( PLA, PETG, PA, PP, ABS, etc.) can be milled easily. You need to be train on the milling strategies and end mills selection and this an easy part of this technology.

The main architecture of a CNC milling center is 3 axises XYZ. There can be added more as A Axis a rotation axis ( rotates on Y or X axis horizontally or vertically and this depends on the machine architecture while mill the model arround like a ring ), B or C axis that replace the milling table there the model can be milled in multiple sides.

The steppers or servos that are used to move the axises with torque, speed and accuracy, are from NEMA 23 up to NEMA 42 ( stepper or servo motors ) and way bigger for servo motors for HUGE multiaxis milling centers ( HAAS, HURCO, DOOSAN are only for reference ).

Anybody can build a DIY milling center or router for hobby use or profesional use ( yes it is possible ) and combine it with FFF printing.

There are lots of tricks and knowledge on how to combine these two techs while this can open a whole new manufacturing horizon.

Just Google DIY cnc and you’ll see many tutorials to build your own milling center.

I’m here to help enyone of you while my experience exceeds 25 years of using and building cnc milling centers.

Ok, this could not be a helpfull video to understand of what a CNC milling center can do, but it is a very sample of what a full 5 axis milling center is capable of.…p=wgIECgIIAQ==