Home Shop Accessories Inc.


How to make a Constant Force Spring


Application: Z axis Counterbalance for

Miniature Milling Machines



The Home Shop Accessories constant force air spring will solve all your problems with Z axis counterbalance in a very inexpensive, compact, efficient, and fully adjustable package. 

(Using an inexpensive air cylinder and a soda bottle!)


The 4 page, full color plans describe the construction of a constant force spring that will counterbalance any load from 1 to 30 lbs or more under dynamic conditions.  Mounting options are wide open and depend on your machine and requirements.  Can be made to work with any mini mill.  Sherline, Taig, Harbor Freight, Import, or whatever!


(Note: Plans describe the construction of the spring only - individual applications will vary)


Only $10


Plans will be emailed to you (Adobe .pdf format) within a few hours of payment.