Fixturing with the Bantam Tools Desktop CNC Spoilboard

Our 7" x 9" Bantam Tools Desktop CNC Spoilboard gives you more fixturing options when working with our Bantam Tools Desktop CNC Milling Machine. While you can machine a variety of metals, engineering plastics, and hardwoods, the Desktop CNC Spoilboard is a must-have if you're machining circuit boards. 

Our Bantam Tools Desktop CNC Spoilboard comes with the following items:

• Spoilboard
• Alignment Jig
• Alignment Jig Screws (3)
• Screws, M5 x 16 (6)
• Hex key, 3mm/2mm 

Now let’s install the Bantam Tools Desktop CNC Spoilboard.

1. Remove the tall alignment bracket, toe clamps, and stock so you can access the screws (For more details, check out our bracket alignment guide.)
2. Remove the six screws holding the T-slot bed to the carriage.
3. Place the spoilboard. Two pegs help align it.
4. Place the six screws that came with your spoilboard and loosely thread them.
5. Then tighten the screws, alternating back and forth between the sides.

To fixture you stock to the Desktop CNC Spoilboard, you'll want to use high-strength, double-sided Nitto tape. Double-sided tape has adhesive on both sides. It bonds two surfaces together—in this case, your material and the bed of the Bantam Tools Desktop CNC Milling Machine. We recommend using high-strength, double-sided Nitto tape. This fixturing method is useful when you’re machining thinner pieces of stock—like FR-1. 

Installing the PCB Bracket

The Bantam Tools Desktop CNC Spoilboard also comes with a PCB bracket. The PCB bracket makes it easier to ensure your stock is square when you set up your job. To install the PCB bracket, line it up with the holes on the front of the Desktop CNC Spoilboard, place the screws in each of the holes, and then use the hex key to tighten them. 

Before you set up your stock, you'll need to probe the bracket using the Bantam Tools Milling Machine Software. To install the PCB bracket complete the following steps:

1. Go to the Jog menu and install your 1/4" probe.
2. Then go to the Initial Setup tab, click the Brackets and Accessories dropdown menu, and select "Locate."
3. Follow the prompts in the pop-up window to locate the bracket. On the flip side, if you've removed the PCB bracket from the spoilboard, select "Remove" to let the Bantam Tools software it's no longer installed. 

How to Use Double-Sided Nitto Tape:

1. Make sure the T-slot bed is free of dust, swarf, glue, or anything else that might prevent the tape from sticking or the material from laying flat. We recommend cleaning it with  91% isopropyl alcohol and a lint-free wipe.

2. Place multiple strips of tape side-by-side (not overlapping or wrinkling) across the back of your material, rubbing it in place to make sure it’s fully adhered to the material. Remove the adhesive backing if you’re using high-strength double-sided tape.

3. Align your material in the machine and press down firmly.

4. To account for the thickness of the tape, enter the tape thickness measurement in the software in the Material Placement (Z) field. High-strength double-sided tape tends to be about 0.006" to 0.007" thick. 

5. Mill your project.

6. When you’re done milling, use isopropyl alcohol to release the high-strength double-sided tape. Have isopropyl alcohol handy if you’re using high-strength double-sided tape.

What kinds of materials is double-sided tape not good for?

Double-sided tape isn’t a good choice for materials that are taller than they are wide because they can tip over. The exception is materials that are very soft, such as machining wax, but there are still limits, which we estimate to be a height 1.5 times the width. For materials that are taller than they are wide, you’ll want to use the L-bracket and toe clamps to fixture your material onto the Desktop CNC Milling Machine’s T-slot bed. 

Are there any problems I might encounter when using double-sided tape?

If your tool mills through the tape, the adhesive may stick to the tip of the tool, along with swarf. This reduces the cutting ability of the tool. You can fix this by wiping the tip with alcohol, which will dissolve the adhesive.

The other issue you may encounter is the material coming loose while you’re milling it. There are a few fixes for this:

• Wipe the bed with 91% isopropyl alcohol before fixturing your stock using tape. Allow the alcohol to completely evaporate before placing the material onto the bed.
• Cover as much surface area of the stock as possible with the double-sided tape. The strips of tape can be right next to each other. Just don't allow them to overlap, wrinkle, or pick up pieces of debris because this impacts your Z height. 
• Reduce your feed rate.
• Reduce your pass depth.