This post will show you how to build a cheap, light, but sturdy metal detector straight shaft for less than $40!
I originally wrote this post because I built a metal detector and did not have a shaft to use with it, but if you are tired of using the stock metal detector shaft that came with your unit, just follow the instructions below and youll have a straight shaft which can be adapted to any metal detector kit.
Benefits
The benefits of a straight shaft include:
- Less fatigue from unbalanced weight distribution
- Lighter
- Customizable arm and mounting positions for weight distribution
- Cool factor
Parts
Items youll need:
- 47″ Metal Extension Pole (I purchased mine at Orchard Supply and Hardware for $5.99 part #WP-00244).
- Rav-X Era X Bar Ends (Found on ebay for $9.99).
- Metal Detector Shaft lock off ebay ($12).
- Tesoro Lower Arm with Hardware ($10.20 SKU#POLE-LOW. comes with coil mounting hardware. OPTIONAL if you are just making the straight shaft to upgrade your current metal detector shaft – take the old one off and put it on this one).
- Garrett Arm Cuff for AT Series ($3.95 SKU#9850601. OPTIONAL if you are just making the straight shaft to upgrade your current metal detector shaft – take the old one off and put it on this one).
- 6-32 1″ round head machine screw (to secure the arm cuff to the shaft), and split lock washer.
- 4mm Allen wrench for tightening the bar end.
- 25/64 drill bit (for the arm cuff hole).
- 5/32 drill bit (for the arm cuff screw).
- 5/64Â tiny drill bit.
Step 1: Cut the Plastic Clad Metal Extension Pole to 39″
Cut the straight shaft to length
Step 2: Locate where you want the arm cuff to be placed and drill a hole using the 25/64 drill bit. I found it helpful to drill several holes in case you want to adjust the cuff out on the field. DO NOT DRILL ALL THE WAY THROUGH, just drill a hole through one side of the pole. You will need to drill a smaller diameter hole for the screw to secure the arm cuff on the opposing side of this 25/64 hole.
Drill hole for the arm cuff using the 25/64 drill bit
Step 3: Place the Garrett arm cuff in the hole you just drilled and use a drill bit small enough to drill through the threaded hole without damaging the screw threads (5/64 drill bit). Drill vertically and as straight as possible, so the hole being made lines up with the screw threads.
Drill within the screw threads to make a small hole on the opposite side of the metal shaft
Step 4: Widen the tiny hole made on the other side of the shaft with a 5/32 drill bit. This hole is for the machine screw to fit through.
Flip the Shaft over and widen the small hole made in the last step
Step 5: Place the split lock washer and 6-32 1″ machine screw into the arm cuff shaft hole and tighten.
Insert the screw with locking washer into the hole to thread into the arm cuff threads
Step 6: Slide the Era X Bar end handle onto the shaft and place according to best fit and feel. The bar end should be placed so the slight angle is pointed away from the arm cuff. Tighten with 4mm allen wrench.
Rav-X bar end
Step 8: Place and tighten the Shaft lock onto the end of the main shaft.
Shaft Lock for metal detector
Step 9: Insert the Tesoro Lower Rod into the shaft lock.
Lower rod assembled
Step 10: Drill holes to fit existing metal detector kit onto shaft using mounting holes as a template.
I didnt need to drill any holes to mount my DIY metal detector kit onto this shaft. Instead I used electrical conduit wall hangers that I found for $.50 at Home Depot.
Conduit Wall hangers
wall hanger installed
Inside mounting of wall hanger and kit (I used shorter screws to mount the hanger to the box)
Kit and hanger mount on rod
Kit mounted on shaft (this picture was taken from my other shaft with tesoro arm cuff)
Step 11: Enjoy your handy work!
DIY straight shaft for metal detectors (oops, I forgot to pull off the white label wrapped around the pole!)
Finished Metal Detector with coil and shaft
I was pretty impressed that this shaft was sturdy, and surprisingly lightweight compared to the plugger straight shaft I have on my tesoro sand shark.
Need ideas and a source on coil housings?
Check out my post on how to use a thermo-formed plastic clamshell to build a durable (and good looking) DIY metal detector coil housing.
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Whats the OD of the Metal Extension Pole?
Just measured with my caliper. OD came out to be .86 inches, or 21.84mm
It’s too bad MetalDetector.com has decided to gouge Canadian customers. They want close to $40 shipping to send the arm cuff by plain mail. Should cost them 1/10th of that to send it at best.
That box is hideous! I tried it and then switched my Surf PI circuit board into a 1-1/2 pvc pipe.
Hi I have tride building my own metal detector for about a year now and I have build 3 deferent types and olny one of them worked but it wasn’t that good, I have tried to get the 1.2pi kit but it is not available in South Africa and if any one can help me please al I need is n list of the components and a diagram of the surcit bord please please can enyone help me I would relay appreciate it I have got everything except for that and it is hard to find or if any one know of a place in South Africa where I can get a kit that wont cost me a fortune I would really appreciate it thank you
:I like the size and general shape of the box. Where did it come from?
Hi. I have upgraded two of my beginners/El Cheapo Harbor Freight detectors with slight changes from this design. I found 2 telescoping extension rods, the type that you turn a quarter turn to unlock. I cut off the threads so the coil could be mounted directly to the rods. I had to unsolder the coil wires as they were internally mounted. I bought different model handlebar ends from eBay and the cuff for the Garrett. One mod I used on the 2nd one was I bought a forearm crutch from a Goodwill store and used the cuff from it. It works better that the Garret cuff as it wraps 3/4 s around my arm. If there is a way to post pictures, I can send them later. Steve Fortune of Boise, ID
Hi dear I’m from iran and in my country is not credit card may you send a pdf of this surf pi metal detector for me please
My metal detector did not have a sturdy shaft and a proper lightweight. For that I replace it with Garrett Arm Cuff At series and it make my shaft sturdy, a proper lightweight at a cheap price $3.97.