Mighty Multitool

This is an instructable I created for the Indestructables contest and to have a handy little multitool. I built it out of a socket wrench, an adjustable wrench, and a broken multitool I've had bouncing around in my toolbox that I couldn't bring myself to throw away, because I can rarely bring myself around to throw anything away. Anyhow, the idea is simple, and I wanted a project to try out an arc welder I recently bought. Also I will apologize in advance for the quality of my welds, I haven't welded in several years and my experience back then was limited. 

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Step 1: Materials and Equipment

Materials Used:
8" Adjustable Wrench
Socket Wrench
Broken Multitool
2 4 " Mending Plates
1/16" electrotrodes

Equipment Used:
Emory Cloth
Dremel with Sanding and Grinding Wheel
Hex keys(to fasten/unfasten screws that hold the tools onto the multitool
70 Amp Arc Welder
Chipping Hammer/Wire Brush
Welding Safety Equipment
-Heavy Leather Gloves and Apron
-Welding Mask/Helmet

Step 2: Sand/Grind the Parts Clean

One of the most important steps in this project is to use a grinding/sanding attachment on a rotary tool, or an emory cloth, to clean the parts to be welded together. It is very important to have clean surfaces to conduct the electricity well with the arc welder.  

Step 3: Reassemble the Multitool W/ the Mending Plates

In this step I took the parts from the broken multitool and placed them between the two 4" mending brackets. I choose the two screwdrivers, the knife, the saw, and the can/bottle opener. Remember to include the spacer washers between the tools so they will swing freely and still have enough friction and spring pressure to hold open when the tool is in use.

Step 4: Weld the Parts Together!

First I fit all the places together to get the desired placement so I know where to weld them together and still have the rotation of the multitool and be able to use the wrenches.
Then I welded the socket wrench to the adjustable wrench. I clamped the two tools together so the heads of the adjustable wrench and socket wrench are aligned on the same plane.
Next I fit the mending brackets over the two wrenches welded together. Then I welded the ends of the brackets to the wrenches.

When I made my welds I tried to keep the electrode at a 45 degree angle. My little welder can only handle 1/16" electrodes so I made several passes each time I welded. Between each pass I used a wire brush and chipping hammer to clean the slag off and prepare the material for the next pass.
IMPORTANT: Always follow safety procedures for using an Arc Welder and Wear Proper Personal Protection Equipment. You can injure yourself or others severely if you aren't careful
An Instructable that is a good read for an introduction to welding and safety precautions is https://www.instructables.com/id/Learning-to-Weld/#step1 

Step 5: Grind and Clean the Finished Welded Mighty Multitool!

The Final Step is to grind and clean the finished piece so any burrs or sharp edges produced by welding spatter won't render the tool a pain to use.

Indestructibles Contest

Finalist in the
Indestructibles Contest



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    11 Discussions


    1 year ago on Introduction

    cool concept but it's a TERRIBLE idea to weld galvanized steel! i hope you've managed to find a safer way to make this.


    1 year ago

    OMG just found this...Really how dangerous is that thing ! Instructables should have taken this down a LONG time ago. That is HOW NOT to make a multitool unless you are looking for an injury.


    6 years ago

    That's a waist of good tools


    6 years ago on Introduction

    Ha - I love it! It looks unwieldy and rough and totally Mad Max - I want one!! Thanks for making this!


    6 years ago on Introduction

    What a "tool"! *Much sarcasm and pun intended* :-) Love the idea, I may make one of these to keep in the car. Good work.

    KlockworkKevinPhil B

    Reply 6 years ago on Introduction

    You're Welcome, it was really helpful to remember a lot of the how to and safety I'd forgotten and learn some things I'd missed the first time I tried welding.


    6 years ago

    Lol cool, now that's a multi tool!