Murphy Barrett’s Work

Vermont Technical College

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     Aaron Todd, Nathaniel Kemp and I began working on designs for a Spring Loaded Camming Device (SCLD) used in climbing.  We drew up a concept sketch for a steel or aluminum body piece, Concept for Body, then a more detailed one with details on the Jaw pieces,

Concept w/ Jaw detail, we began work.  To date I have developed the Jaw pieces, the first one of which was abandoned due to complications in creating schematics. (Jaw Design 1)  The second Jaw design utilized a single spline instead of the multiple splines of the previous design.  Jaw 2 was much easier to dimension and it should be easier to create since it is a simpler part.


Assignment 1 (Mec 1011 Review (Spud Gun))

·       Design Guide

·       Full Assembly

·       Barrel Assembly

o      Barrel

o      Cap

o      Mount Bracket

·       Base Assembly

o      Mount Base

o      Stand Pipe

o      Base Plate


Challenge (Skateboard thing)

·       Flange Bearing Adapter

·       Flange

·       Ball


Project 1 SLCD

·       Body

·       Jaws

·       Concept Sketches

o      1st


·       Real World Cams (for Comparison)

o      Diagram

o      Quad Placement

o      TechFriend Cam

o      Camelot Cam

o      Camelot Expand

o      Single Stem

o      Flexible U Stems

o      3 vs 4 Head

·       Random Concept Sketches

o       2


To Sword

(Note:  It is pronounced “toe” Sword)

Design Guide for Sword

·       Mark I

The MkI was the initial design of a Japanese To style sword intended for mass production and issue to military units.  However, it possessed a huge flaw.  It was not field reparable.  The handle was intended to be made of a rubber based material.  Unfortunately, rubber tends to wear out.  The sword was designed to be able to function without the rubber handle by having the tang run the full length and width of the handle.  However, once the handle broke it would not be able to be easily removed.  The rivets used could only be punched in a factory and are not easy to remove in the field.

o      Sword

o      Blade

o      Hilt

o      Rivet

·       Mark II

The MkII was designed to address the flaw of the MkI design.  Instead of using the rivets of the MkI, the MkII uses screws that can be found in any hardware store and can be screwed in or out with a multi-tool or small bladed knife.  The screws are still flush with the handle.  Additionally, the handle has been thickened by a 1/8 of an inch for comfort and grip.  Only one side of the handle has screw holes, but the screws can be on either side of the weapon.  It does not matter.  The holes in the blade designed to receive the screws are now threaded as well, so no nuts are needed.  And, as with the MkII, if the handle is removed and no replacement is available, the blade alone can be used as the sword.

o      Sword

o      Blade

o      Hilt

·       Mark III

The MkIII was an experiment to allow added utility to the weapon.  A hook was added to the end of the blade to allow ropes or carabineers to be attached for the purposes of assisted climbing.  However, while the idea was sound, the hook was a poor solution and will be addressed in the MkIV.  (Note:  The MkIII uses the MkII handle.)

o      Sword

o      Blade

o      Hilt


After discussing my idea with several friends who are familiar with both military needs and the needs of a good sword, the To Blade has split into a number of options.  The new idea is that the customer orders the blade design of their choice and the matching hilt.  Hilts are available in two lengths that interface with any blade of the matching handle length.  Additionally, it is feasible to offer blades made of different types of steel, from low grade to tool steels.



·       Mark IV

·       A

The MkIV-A is intended to be the “basic” model.  It is altered from the MkIII in that instead of a cable hook the end of the hilt is now a pry bar tool with a hole drilled into it so that a cord can still be run through.  It is available in two hilt lengths, 12-inch and 8-inch.  12- inch allows for a two handed grip, my personal preference, and the 8-inch is a one handed grip likely to be preferred by most people.

·       Blade MkIV-A8

·       Blade MkIV-A12

·       B

The MkIV-B is a minor variant of the MkIV-A.  Instead of a smooth back edge, the back edge has been machined into a saw blade suitable for felling small trees.  It was also pointed out to me by one of my friends that the saw edge is so aggressive that it would also be useful for felling biological targets.  Unfortunately, making the back edge a saw potentially weakens the blade as a whole, but that issue can be circumvented by ordering the blade of a better steel.

·       Blade MkIV-B8

·       Blade MkIV-B12


·       Mark V

                        The Mark V Blade is another variation upon the basic model.  Instead of the 1.5 inch blade, the

Mk V has a two inch think blade and no option of saw edge, as the added weight of the blade will allow easy cutting in a similar manner to a machete.  It has been described as the illegitimate mutated bastard child of a Katana and Machete.

·       A

The Mk V A is currently the only variant in existence as no other variants have yet been developed.

·       Blade MkV-A8

·       Blade MkV-A12



          In order to allow people to get better quality hilts without undue expense, three basic models have been developed.  The basic model is made from a standard rubber.  The two halves of the hilt would be screwed together using a male-female screw custom designed for the purpose.  They are the same screws used in the Paracord and Leather hilts.

There are two variations of the rubber hilt, the basic model and a model with a small guard.  However, I do not expect the guard to market well and so it will not be fielded.  My fiend Kevin recommended making two upgrades to the hilt, a leather and a whipped variant.  The whipped version is made using two hardwood halves screwed together and whipped with paracord.  The most expensive leather model involves screwing in the same wood halves as the paracord model, and the wrapping the hilt in ˝ strips of soaked rawhide.  The rawhide will dry and shrink, making the hilt permanent.  In addition, leather hilts tend to feel better in the hand and be more resilient than other models.  I also developed a bayonet hilt for the 8 inch hilt only.  It is not, nor will it be finished as it is nearly unworkable and actually a bad design all together, but I will display it to demonstrate what failed plans look like.




·       Hilt-Rubber8

·       Hilt-Rubber12

·       Male Screw

·       Female Screw




·       HiltHalf-8

·       HiltHalf-12

·       Male Screw

·       Female Screw

·       Hilt Assembly



·       Assembly

·       Center Lug

·       Sides


Scimitar Sword

          Design Guide

          Continuing my trend of blade design, I decided to design another style of sword.  This one is a scimitar with a drop point tip.  Drop point means that the tip curves in along the center line of the blade.  It used drop point because it is a personal preference.  I started with on design, the MkI.  However, that wouldn’t work because the tip was too narrow and would break off quickly.  I then designed the MkII, however that had basically the same problem.  Also the blade would be a bit heavy for me.  I began experimenting with different designs, eventually developing ten different blades.  After analysis, I decided to finish designing the MkVIIA, as it will be light enough for me to handle, fast enough for my style, and the tip is strong enough for continued wear.


          Blade Study







Drawing Files

Image Files





Scale Rt.

Scale Rt.

Scale Lt.

Scale Lt.







Drop Ship


        I decided to design this Drop Ship just to see if I could.  I took about six hours do make the basic body correctly, and several more hours to get the details.  The most difficult part was creating the cockpit as it had to basically be hollowed out.  The design is a combination of the Pelican ship from HALO, an Air Force C-130 Hercules, and my own ideas.  The ship has 6000 cubic feet of cargo space and is comparable in size to a Hercules.

        In the full assembly there is a Bunk Unit and a Chair that I borrowed from some of my earlier projects.



·       General View

·       Dimension Drawings

o     Dorsal

o     Ventral

o     Fore

o     Rear

o     Side

·       Cutaway Views