Many shops do external or surface grinding. However, when you have round items which need internal grinding or finishing, it’s a totally different operation. Here are some important things to know about internal diameter or ID grinding, to help you produce more pieces and improve quality.
Setup
When you set up for an internal diameter job, you need to use the right tools for grinding a specific metal. However, some of these rules don’t always apply to internal methods.
You May Need Different Tools
Suppose your shop does a lot of OD work. If you use the same wheels for internal grinding, you could have problems with chatter, and this can ruin your work. Also, metal burning is a real possibility. You can avoid many of these issues by using a wheel with slightly softer abrasives.
Carbon Steel
For carbon steel, consider using aluminum oxide or cubic boron nitride (CBN). CBN gives you several benefits for ID grinding:
- Almost as hard as diamond cutting tools
- Exceptional strength
- Resistant to abrasion
- Resists heat and chemicals
- Stays sharp for a long time (it does not react with steel)
Softer Metals
Cast iron and aluminum can present several problems when grinding. For example, chips can easily build up and affect efficiency, performance, and accuracy. For softer metals, you need extremely hard cutting tools like diamond coated tools or silicon carbide.
Removing Stock
When you need to grind a lot of material at one time, it’s important to use coarse-grained abrasives. However, for hard metals like hardened steel, a fine grain abrasive may work best. Fine abrasives have more cutting points so they can remove material at a faster rate.
Professional Help
If your shop doesn’t do a lot of ID grinding, consider hiring a trusted shop known for its quality grinding work. This makes it easier for you and your people.
