Vertical Metal Band Saw: Blade Selection, Setup, and Cut Quality
You need to cut metal on a vertical band saw and you want to know how to set it up for good cut quality. Vertical metal band saws are used for contour cutting, straight cutting, and irregular shape cutting in metal. You need to know what blade to use, what speed to set, and how to feed the material for clean cuts.
A vertical metal band saw is a saw where the blade runs vertically between two wheels, and the workpiece is fed into the blade on a table. Vertical metal cutting saws are designed for cutting metal with variable speed, coolant systems, and heavy construction.
Types of Vertical Metal Band Saws
Dedicated Metal Cutting Saws
Saws designed specifically for metal cutting with variable speed (40 to 1000 FPM), coolant systems, and heavy construction.
Examples: DoAll, Wellsaw, Clausing, Dake. Best for: Production metal cutting, contour cutting.
Combination Wood/Metal Saws
Woodworking saws with variable speed that can be reduced for metal cutting.
Examples: Some Grizzly and Jet models with variable speed. Best for: Occasional metal cutting in a woodworking shop.
Important: Most woodworking saws run at 2500 to 3500 FPM, which is too fast for metal. Only use a woodworking saw for metal if it has variable speed that can be reduced to 40 to 500 FPM.
Blade Selection
Blade Material
Bi-metal M42: The standard for metal cutting. M42 high-speed steel edge on flexible spring steel backing. Handles mild steel, stainless steel, aluminum, brass, copper, cast iron. Cost: 15 to 35 dollars.
Bi-metal M51: Harder edge for tough materials like stainless steel. Cost: 20 to 45 dollars.
Carbide-tipped: The longest lasting. For production cutting. Cost: 50 to 150 dollars.
TPI Selection
| TPI | Best For | Material Thickness |
|---|---|---|
| 6 to 8 TPI | Thick solid bar | 1 to 4 inches |
| 10 TPI | General metal cutting | 1/4 to 2 inches |
| 14 TPI | Medium thickness | 1/8 to 1 inch |
| 18 TPI | Thin material | Under 1/4 inch |
| 24 TPI | Very thin material | Under 1/8 inch |
| 10/14 variable pitch | Mixed thicknesses | All |
Rule of thumb: At least 3 teeth should be in the material at all times.
Tooth Profile
Standard tooth (0 degree rake): Good balance of cutting speed and surface finish. The most common profile.
Hook tooth (positive rake): Cuts aggressively. Best for thick stock.
Skip tooth (large gullet): Good for soft or gummy materials like aluminum.
Regular tooth (negative rake): Smoothest finish. Best for thin material.
Blade Width for Contour Cutting
For contour cutting, use a narrow blade that can handle the curve radius.
| Blade Width | Minimum Cut Radius |
|---|---|
| 1/8 inch | 5/16 inch |
| 3/16 inch | 5/8 inch |
| 1/4 inch | 7/8 inch |
| 3/8 inch | 1-1/2 inches |
| 1/2 inch | 2-1/2 inches |
Speed Selection
Recommended Blade Speeds by Material
| Material | Speed (FPM) |
|---|---|
| Mild steel (thick) | 60 to 100 |
| Mild steel (medium) | 100 to 200 |
| Mild steel (thin) | 200 to 300 |
| Stainless steel | 60 to 100 |
| Aluminum | 200 to 400 |
| Brass and copper | 100 to 200 |
| Cast iron | 80 to 150 |
How to Set the Speed
Step pulley: Change the belt position on the pulleys. Variable speed (mechanical): Adjust the dial. Variable speed (hydraulic): Adjust the hydraulic speed control.
Feed Rate
How to Feed Material
Light feed: For thin or hard material. Let the blade do the work. Do not force the cut. Medium feed: For medium-thickness material. Apply steady, moderate pressure. Heavy feed: For thick or soft material. Apply firm pressure but do not force the blade.
Signs of Incorrect Feed Rate
Too fast: Blade stalling, rough cut surface, short blade life, broken teeth. Too slow: Burning (blue discoloration), slow cutting, premature dulling from rubbing.
Coolant
When to Use Coolant
Use coolant for: Steel, stainless steel, and thick material. Skip coolant for: Aluminum (can load the blade), brass, thin material.
Coolant Types
Cutting fluid: Formulated for metal cutting. Best for most applications. Water-soluble oil: Mixed with water. Common in shop use. Synthetic coolant: Water-based, no oil. Cleaner.
Applying Coolant
Direct the coolant nozzle at the blade-workpiece contact point. Adjust the flow to keep the cut area wet without excessive flooding.
Setup Procedure
1. Install the Blade
- Open the wheel covers.
- Release blade tension.
- Install the blade with teeth pointing down (toward the table).
- Apply tension to the recommended setting.
- Check tracking.
- Close the wheel covers.
2. Set the Speed
- Determine the material and thickness.
- Look up the recommended speed.
- Set the speed using the step pulleys or variable speed control.
3. Adjust the Blade Guides
- Set the side guides about 1/32 inch from the blade sides.
- Set the thrust bearing about 1/64 inch behind the blade.
- Set the guide post height about 1/4 inch above the workpiece.
4. Set Up Coolant (if applicable)
- Fill the coolant tank.
- Position the nozzle at the blade-workpiece contact point.
- Turn on the coolant pump and adjust the flow.
5. Make the Cut
- Turn on the saw and let it reach full speed.
- Feed the material into the blade with steady pressure.
- Do not force the cut. Let the blade do the work.
- For contour cuts, follow the layout line carefully.
Achieving Good Cut Quality
Factors That Affect Cut Quality
- Blade sharpness: A sharp blade produces smooth cuts. Replace the blade when cuts become rough.
- Correct TPI: At least 3 teeth in the material. Too few teeth produces rough cuts. Too many teeth produces slow cutting and blade loading.
- Correct speed: Too fast burns the material. Too slow dulls the blade.
- Correct feed rate: Too fast produces rough cuts and short blade life. Too slow produces burning and dulling.
- Coolant: Coolant improves cut quality and blade life.
- Blade guides: Properly adjusted guides prevent blade wander and produce straight cuts.
FAQ
Can I cut metal on a woodworking band saw?
Only if the saw has variable speed that can be reduced to 40 to 500 FPM. Most woodworking saws run at 2500 to 3500 FPM, which is too fast for metal and will destroy the blade.
What blade should I use for cutting mild steel on a vertical band saw?
A 10 to 14 TPI bi-metal M42 blade for general cutting. 6 to 8 TPI for thick material. 18 to 24 TPI for thin material. 10/14 variable pitch for mixed thicknesses.
What speed should I use for cutting steel on a vertical band saw?
60 to 100 FPM for thick steel. 100 to 200 FPM for medium thickness. 200 to 300 FPM for thin steel. Use the variable speed control to set the speed.
Do I need coolant for vertical metal band saw cutting?
Yes, for steel and stainless steel. Coolant extends blade life, improves cut quality, and clears chips. For aluminum, skip coolant as it can load the blade.
How do I achieve smooth cuts on a vertical metal band saw?
Use a sharp blade with the correct TPI, set the correct speed, feed at a steady rate, use coolant, and adjust the blade guides properly.
References
- DoAll Saw. “Vertical Metal Cutting Band Saw Guide.” DoAll Saw Company.
- LENOX Tools. “Metal Cutting Blade Selection Guide.” LENOX Industrial Division.
- Starrett. “Bi-Metal Blade Specifications.” L.S. Starrett Company.
- Practical Machinist. “Vertical Metal Band Saw Setup Tips.” practicalmachinist.com.
- Modern Machine Shop. “Band Saw Cutting Speeds and Feeds.” Gardner Business Media.
