Helpful Tips

Although M-3 offers both single and dual systems, the dual system is recommended on doors weighing 120# or more.  The dual-spring system offers greater flexibility when balancing a ramp door.  Safety is another key issue.  Since both springs are mounted on a common shaft, if one should happen to break the second spring is still […]

Unusual Trailer Size – Custom Options

Spring weights – Springs are stocked at M-3 to handle doors with springing weights of 45 lbs through 300 lbs. 205 lbs through 300 lbs systems have a center bearing plate and weld bracket assembly for added support. Drum sizes – Standard M-3 drums are 4” diameter. Both 3” diameter and 6” diameter drums are […]

Positioning the Cable Drums

Questions regarding the placement of cable drums (spools) usually fall into one of two categories. First – “I bought an 81” wide system but my trailer is only 75” wide.  Can I cut it down?  Where do I re-position the spools?” Answer – The drums (spools) are never placed exactly where they will be on […]

Cable Jumps Off Drum

Customer has installed spring assist system on a “used” trailer.  After winding the spring the door opens and closes but the cable on one side “jumps” off of the cable spool, pulley, or drum. Things to check – cable anchor brackets are the same distance down on both sides of the door. Suggested fix – […]

Altering the Length of the Tube On Spring Systems

The tube on spring systems can be shortened by cutting the tube with a hacksaw and re-positioning the component parts on the resulting narrower tube. Here’s how to determine the minimum possible tube length: The springs will grow in length as they are wound so it is possible to cut a tube too short.  Here […]

How to Measure for a Ramp Door Spring Assist System?

Critical measurements: Springing weight – Weight of the ramp at the beginning of the spring cycle. Determined by placing a scale under the open door with no spring system attached. Door Height – It is also helpful to know the distance from the top of the door to the end of the open door. This […]