Modular Ratchet System

This is a group report made by a group of 5 including myself during the Spring 2018 semester, at Houston Community College. We designed a modular ratchet system, and looked at how feasible it would be to produce them based on cost of materials and labor.

Modular Ratchet System

General πnamics (GRUP3)

 

 

 

 

INSTRUCTOR: Prof. Abdul Qureshi

COURSE: ENGR-1204

CLASS NO: 52764

 

TEAM MEMBERS:

Damian Kao

Paulo Cisneros

Roy Welsh

 Steven Smith

Yan Ng

Problem Statement 

Creating a Modular Ratchet System that is cost effective, and versatile, capable of handling the tasks done by two separate tools.

Introduction

General πnamics (GRUP3) is proud to introduce the Modular Ratchet System. The Modular Ratchet System (MRS) is a standard 1/2” ratchet with a handle that will securely attach an extension for use when high torque is needed. The MRS eliminates the need for a seperate ratchet and breaker bar, considerably reducing expense for the end user.

Group Member Roles

Damian Kao - Sketches and drafting Group Report.

Paulo Cisneros - Design Idea and Power Point Presentation.

Roy Welsh - Group Leader and Autodesk Inventor artist.

Steven Smith - Original idea and powerpoint presentation.

Yan Ng - Research material choice and manufacturing cost.

Executive Summary

Mechanics often encounter bolts that are rusted in place, or are otherwise extremely difficult to remove. They often have to improvise, jury rigging their ratchets with pipes in order to apply more torque. This can pose a risk of injury to the user. Specialized tools such as breaker bars exist, but they are rarely used, are more expensive than regular ratchets and spend most of their time taking up space in a toolbox. Workers that use hand tools all understand the high price of tools. Our idea aims to replace a set of tools that all individually are around the same suggested price of our tool with a small modification that makes it much safer to use. 

Discussion

The team is developing a modular attachment system for a ratchet to allow an extension to be added to a ratchet for working with high torque situations. The primary attachment will add an extension to the ratchet, and will have a flat surface, making it easy to use a soft sole boot, hammer or other improvised items to exert force on the ratchet. The attachment will securely attach without the need for additional tools, and there are a variety of other attachments that could be used with this attachment system.

Design and Specifications

The initial offering is a ½” adjustable ratchet with an 8” handle. Attachments will be available in various sizes, starting off at 11” long, effectively adding an additional 8” to the length of the handle. The extension will double the mechanical advantage of the ratchet.

Design Discussion

There are aspects of this easy to use tool that lend themselves perfectly to commercial and industrial use. The attachment is easy to quickly add or remove as needed, and does not reduce the strength of the ratchet. There were three specific designs that we discussed and the most efficient, safest, and easiest to manufacture design won out against the other designs.

Materials

The Modular Ratchet System will be produced using 4130 chromoly which is a steel alloy commonly used in automotive, bicycle, and heavy equipment tooling (ASTM). Chromoly 4130 contains chromium and molybdenum among its alloying elements and it follows the American Iron and Steel Institute (AISI) 41xx standards (ASTM). The first two digits, 41, indicate that the main elements are chromium and molybdenum. The last two digits, 30, indicate that the allow contains 0.30% carbon (ASTM).

Molybdenum in chromoly increases the corrosion resistance and strength of steel as well as the elastic limit, resistance to wear, impact qualities, and hardenability (ASTM). Chromium in chromoly is the essential constituent of stainless steel and it raises the tensile, yield, and hardness of the alloy (ASTM). Chromoly 4130 is extremely strong, while not being excessively heavy and has decent corrosion resistance by itself. Using Chromoly 4130 as the main material will make the ratchet highly durable

Cost for Manufacturing 1000 Ratchets

Discussed ideas:

1. Using a pin mechanism to fasten the two components. This was rejected because it consisted of an additional pin that could potentially get misplaced.

2. Using a model of the attachment that was rectangular in design to support the use of feet to exert force. This model not be useable by hand due to its hard to grasp shape, as was therefore discarded. 

The Modular Ratchet System (MRS)

The Locking Mechanism

Handle View:

The handle has grooves cut along its length that allows the attachment to slide on, then rotate 90 degrees to lock into place.

Attachment Wireframe View:

This view shows the teeth that interface with the grooves on the handle.

Handle Dimensions:

Attachment Dimensions:

Previous Prototype Design:

An early design that had the ratchet head attached at 90° to the handle.

It was not selected because its rectangular shape would be difficult to use without the attachment due to its sharp corners. It would have also required push pins to hold the attachment in place.

Prototype Sketches:

Result

The result from the design process is a ratchet with an extension that would be able to handle fasteners such as lug-nuts or mounting bolts that are corroded or naturally welded to whatever is being fastened. The ratchet is a normal ratchet using existing technology. The extension is something that is used often. These two pieces of technology have never been sold together with the safe locking mechanisms and safe step.

Usability Comparison

The MRS compares well against its competition. Normal systems use multiple ratchets for multiple torque ranges. The MRS uses one ratchet head for all torque ranges with a changeable handle size. This is more efficient and every mechanic knows that toolbox storage space is valued highly. Nothing else in comparison between other ratchets and the MRS is variable. It efficiently allocates resources to a wider range of problems.

 

Recommendations

• Include a carrying case to hold the two components.

• Including a knurled surface on the handlebar, to give the tool a better grip.

• Making the dual attachment universal, to be able to attach to other forms of ratchets and tools

Conclusion

  What General πnamics has to offer is simple, but unlike any other item available on the market today. It brings together two different tools, that primarily saves money, and is also easy to use. Further adjustments could be made to the design in order to boost quality as well as cost efficiency, but as of right now, it is what every mechanic would want to own.

References

“1/2’ Drive 80-Tooth Industrial Finish Ratchet.” SnaponStore, store.snapon.com/Dual-80-174-Technology-Chrome-1-2--1-2-Drive-80-Tooth-Industrial-Finish-Ratchet-P651020.aspx.

“1/2’ Drive Dual 80® Technology Soft Grip Extra Long Handle Ratchet, Green.” SnaponStore, store.snapon.com/Dual-80-174-Technology-Soft-Grip-1-2--1-2-Drive-Dual-80-reg-Technology-Soft-Grip-Extra-Long-Handle-Ratchet-Green-P892409.aspx.

“ASTM S/A 335 Chrome Moly Pipe | A335 P Grade Piping.” FedSteel.com, fedsteel.com/astm-a335-chrome-moly-pipe/?gclid=CjwKCAjw2dvWBRBvEiwADllhn-aNOSVfN_QcKivZWDAews6qQ_DGksQKvjHCCoL633UzMMCHt_0TgRoCXQQQAvD_BwE.