Hands On
Service Methods and Tips

MAY/JUN 2003
Volume 46/Issue 3

Project Articles
Wall-Hung Curio Cabinet
Mobile Potting Table
Pencil and Stamp Holder

Ask Smitty
Owner’s Gallery
Letters from Owners
Academy Notes
Furniture Joinery
Service Pointers
MARK V Speed Change Mechanism
Safety Tips
Safety Do's and Don'ts

What's New
Shopsmith and Lowe's Team Up

Find A Shopsmith Woodworking Academy Near You

National Woodworking Academy in Dayton, OH

Online Accessory Catalog
Request Printed Accessory Catalog
Online Replacement Parts Catalog

Find A Shopsmith
MARK V Demo Near You

Request MARK V Information Package

Links Worth Visiting
Free Woodworking Tips

Contacting Shopsmith

Copyright 2003.
Shopsmith, Inc.
All Rights Reserved

Service Pointers
MARK V Service Pointers
- Speed Change Mechanism

Printer friendly PDF copy of article

The ease of changing speeds is one of the most desirable features of the Shopsmith MARK V. By adjusting the motor speed between 700 and 5,20 rpm, you can perform a multitude of operations, including sawing, molding, sanding, lathe turning, drilling, shaping and more.

The Shopsmith speed change mechanism relies on sliding sheaves that increase or decrease your MARK V's speed by increasing or decreasing the diameters of driving or driven pulleys. This unique pulley system allows an infinite variation in speeds and enables you to select the exact sped for any given operation.

Such precision parts require regular oiling to ensure the smoothest possible movement - a few drops of lightweight machine oil applied every ten hours of actual running time is recommended.

The speed control mechanism is located inside the MARK V's headstock. Its accuracy depends on regular maintenance. However, sometimes, it demands a little more. Here's a handy, quick-reference trouble-shooting chart for those times.

Problem Possible Cause(s) Remedy
Won't change from high to low speeds

Retaining Loop may be disconnected


Control sheave is sticking

Remove nameplate from back side of headstock and press leaf spring in on the quadrant, then re-hook the loop.

Remove the nameplate from the back side of the headstock. Reach in and try to slide the control sheave. Oil the shaft and work the oil in.

Spindle stops turning when speed dial is turned from high to low Floating sheave is stuck Remove belt cover and oil motor shaft. Move sheave by hand. Belt may have slipped between control and Poly-V sheaves.
Speed dial “creeps” during operation

The spring (504228) may not have sufficient tension


Remove the control handle. Remove the screw that holds the spring and gently bend the flat spring to create added tension.

Very hard to turn speed dial when moving from high to low speed

Sticking sheaves. Keys on shafts may be bent.

Oil both control (504781) and floating(504208) sheaves. If oiling doesn't help, file of any burs or replace the bent key(s).

Speed changes although dial remains at same setting when changing speeds Bad control handle Gear in back may be stripped. Remove control handle and check. If so, replace.
Speed dial turns...but speed remains the same

Worn quadrant



Loop disengaged

Check teeth on quadrant. May be stripped. Remove nameplate from back side of headstock and check. If stripped, replace.

Remove nameplate from back side of headstock and rehook loop onto quadrant.