Replacement of Vari-Speed Belt

Refer to Figures 31 and 32, and Head Assembly in the Parts section.

Disconnect electrical power to the machine before performing any maintenance.

1.Remove drive motor (refer to the Replacement of Drive Motor section).

2.Remove Quill Top Cover by removing three cap screws (Figure 31).

3.Remove six cap screws and remove the upper housing (Figure 32).

4.Remove the vari-speed belt (ref. 4).

5.Install the new vari-speed belt (ref. 4) on the driven hub (ref. 44).

6.Install drive motor (refer to the Replacement of Drive Motor section).

Figure 32

Replacement of Brake Shoes, Springs and/or Timing Belt

Disconnect electrical power to the machine before performing any maintenance.

1.Remove drive motor (refer to the Replacement of Drive Motor section).

2.Remove vari-speed belt and upper housing (refer to the Replacement of Vari-Speed Belt section).

3.Remove screws from lower housing cover (ref. 50).

4.Loosen the setscrew (ref. 3) securing the brake pivot finger stud (ref. 58) in the lower housing cover (ref. 50).

5.Move the pivot finger stud (ref. 58) inward enough to remove the snap ring (ref. 60).

Figure 33

6.Pull the pivot finger stud (ref. 58) out of the lower housing cover (ref. 50) and the brake pivot fingers (ref. 59).

7.Before removing, note the orientation of the brake pivot fingers (ref. 59) for correct positioning for re-assembly. Remove the pivot fingers.

If replacing the brake components only, skip Steps 8 and 9 and go to Step 10.

To replace the timing belt:

8.Remove lower housing cover and pulley.

9.Replace belt (ref 63).

To replace the brake components:

10.Using a soft-faced mallet, tap upward to separate the lower housing cover (ref. 50) and the brake assembly (ref. 47) from the bearing (ref. 43).

11.Remove the brake shoes (ref. 47) and springs (ref. 49). Install the replacement brake shoes and springs.

For all:

12.Position the brake pivot fingers (ref. 59) as noted during removal. Install the pivot finger stud (ref.

58)through the lower housing cover (ref. 50) and into the brake pivot fingers (ref. 59). Install the snap ring (ref. 60) on the pivot finger stud (ref.

58).

13.Tighten the setscrew (ref. 3) to secure the pivot finger stud (ref. 58).

14.Install the brake assembly (ref. 47) on the lower housing cover (ref. 50).

15.Secure the lower housing cover (ref. 50) with four screws.

16.Install timing belt and upper housing.

17.Install vari-speed belt (refer to the Replacement of Vari-Speed Belt section).

18.Install drive motor (refer to the Replacement of Drive Motor section).

JTM-4VS specifications

The Jet Tools JTM-4VS is a highly regarded vertical mill that caters to the demands of both professional machinists and serious hobbyists. This versatile piece of machinery combines precision engineering with innovative features, making it a popular choice in workshops and fabrication shops.

One of the standout characteristics of the JTM-4VS is its powerful 1.5 HP motor that operates on either 115V or 230V power supply, providing flexibility depending on the workshop setup. The motor offers variable speed control, from 60 to 4200 RPM, allowing users to adjust speeds according to the material being machined. This capability makes it ideal for a wide range of applications, from heavy milling on steel to delicate work on softer materials like aluminum.

The JTM-4VS is equipped with a robust cast iron column and base, which contribute to its stability and durability. This construction minimizes vibrations during operation, resulting in improved precision and surface finish on machined parts. The table measures 9” x 49”, providing ample workspace for various projects, and is fitted with T-slots for easy clamping of workpieces.

Another notable feature of the JTM-4VS is its easy-to-use digital readout (DRO) system that assists users in making precise adjustments and measurements. The DRO enhances the overall efficiency of the milling process, allowing operators to focus on the task at hand rather than relying solely on manual measurements.

The machine also incorporates a high-grade, hardened and ground bedway that ensures smooth operation and long-lasting performance. This feature not only extends the longevity of the mill but also allows for precise vertical and horizontal movements.

Safety is a primary concern in any workshop, and Jet has addressed this with various safety features integrated into the JTM-4VS. The mill is designed with a protective shield and emergency stop button, ensuring operators can work confidently.

In summary, the Jet Tools JTM-4VS stands out for its combination of robust construction, versatile functionality, and user-friendly technologies. With its powerful motor, variable speed capabilities, and precision features, it is an excellent investment for anyone looking to enhance their machining capabilities in the workshop. Whether it's for industrial applications or intricate projects, the JTM-4VS delivers reliable performance and exceptional results.