4 Things to Consider When Buying a New VMC
You finally did it. You decided that it’s time to buy a new vertical machining center.
Investing in a new machine can be challenging and requires a lot of research to make sure that the money you will spend will generate a high return.
When deciding what machine is best suited for your operations we recommend going through the following process:
1. Analyze the need
The first thing to consider is the intended application and workpiece(s) and the needs of a shop’s various departments.
2. Spindle speeds, torque, and horsepower
Once that’s figured out the next critical consideration is the rage of spindle speeds, torque and horsepower.
The trends in recent years have been toward coated tooling, smaller tools, shallower depths of cut and higher feed rates. Smaller tools require a higher spindle speed. Faster feeds and speeds deliver better surface finishes. High-speed machining requires less spindle horsepower and torque (twisting force)
when taking smaller cuts.
3. Spindle Taper Size
After selecting the spindle that best meets the horsepower, spindle speed and torque requirements come selecting the type or style of tooling taper and its size. The most commonly used size in the U.S., and the size we recommend, is the CAT40.
This final step is a little more articulated and usually takes place after the selection of the machine is done.
You might want to make sure that you have the right holders, collets and endmills to execute all your operations.
Here’s what we recommend:
The choice of holders is nearly endless.
The list of tool holders that you will need is strictly connected to the tool type and shank size and to the type and depth of cuts you are planning to do.
For a generic initial tool holder set these are our recommendations:
- ER16 holders – short and long
- ER32 holder – short and long
- ER40 holder – long and short
- ¼” endmill holder
- 3/8”endmill holder
- ½” endmill holder
- 5/8” endmill holder
- ¾” endmill holder
- 1” endmill holder
- Facemill holder
- Drill chuck
To save time in the research and get better deals you can also consider buying tool holder sets, especially in the case of collet chucks.
Here is what we recommend.
Collets come in 8 different sizes and 4 different styles. Although it’s pretty common to buy them in sets, we generally recommend getting some extra nominal sizes.
Collet nuts generally come with the tool holder. The most common type of nuts are the flush nuts but there are three other types of collet nuts that might be better, depending on your operations:
- Low-friction nuts – helpful to increase the tool-holding force
- Coolant nuts – ideal for through-spindle coolant tools
- Mini nuts – ideal to reach into tight spaces
No matter what type of nut you’ll end up using, you should always have a good torque wrench to tighten it up.
Here’s what we recommend.
Given the potential cost of a broken pull stud, you should definitely consider investing a little more money to prevent that from happening.
Here’s what we recommend.
The choice of tools that you could use is just too vast and too related to the type of works your machine shop will do to be described in a short paragraph.
Our best recommendation is to carefully analyze the applications, gather information from different tool manufacturers and invest in the most suitable and reliable ones.