Knife Forged From Bicycle Spokes - a Truly Bespoke Knife!

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I set out to make a knife using an unusual material, something I hadn't used before. And a quick search on the web yielded few results of anyone forging a knife from bicycle spokes. At the beginning I wasn't sure if the spoke material was suitable for a knife blade so I did a quick spark test (see step 1) and found there should be sufficient carbon content. However, when later testing the hardness of the quenched blade, it didn't harden to my satisfaction. (EDIT: See below) Even though the finished knife isn't going into active kitchen service, I went on to complete the knife as I was intrigued by the pattern in the blade. And I'm hoping you may learn something from reviewing the steps in my process.

Can bicycle spokes be forge welded into a knife? Yes!

In this instructable I'll show you how I forged 90 bicycle spokes into an 8 inch chef knife. This knife features a full tang, integral forged bolster, stabilised New Zealand native timber and stainless steel pins.

EDIT: We've been using the knife in our kitchen and it's working great, cutting well and comfortable in the hand. We'll be using the knife on a regular basis.

Observations:

The spokes are coated to prevent corrosion. This coating gave off some nasty fumes when heated and also contributed to some gaps in the forge welding which can be seen in the photos. Cleaning the spokes back to shiny steel would probably have resolved these issues.

Supplies:

Bicycle spokes

disc grinder

welder

forge

press

hammer and anvil

power hammer (optional but speeds up forging process)

belt grinder

handle material

epoxy

Personal safety protection (breathing mask, hearing protection, apron, eye protection, steel toe boots)

Teacher Notes

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Step 1: Prepare the Spokes

My donor material came from a couple of old bikes. I removed the tyres and cut the spokes out of the rims.

I cut the spokes into lengths of 110mm then bundled them together using wire. I mig welded one end to hold the spokes in place then attached a length of rebar at the other end to use as a handle when forging.

All up I had 179 lengths of spoke.

During welding it became apparent that some nasty fumes were being burned off the spokes. Good ventilation is needed here so as not to inhale the fumes.

Note
I wanted to check the presence of hardenable material in the spokes. Performing a spark test on the belt grinder resulted in star-burst sparks, a good indicator of the presence of carbon in the spokes.

Step 2: Heating the Spokes and Forge Welding

The bundle of spokes goes into the forge and when beginning to take on color, flux (anhydrous borax) is added to help with welding and drive out impurities.

When the billet had heated thoroughly, I pressed it a few times to tighten the bundle, then placing it in a vice I twisted it to further tighten the billet. By this stage, it was a solid steel mass.

The mig welded end cap is removed using a disc grinder.

Step 3: Forging to Shape

I begin to work the billet into shape, first flattening then drawing out, then introducing a step that will become the bolster and tang.

Check out the video to see the power hammer in operation.

Step 4: Final Forging to Shape

I cut off the rebar handle then forge the bolster and tang to shape. I heat the blade again and allow to slowly cool in vermiculite to anneal the blade.

Step 5: Profile Shaping

The cooled blade is marked with a sharpie then the profile is ground in. I begin to shape the bolster and flat grind the blade.

Finally I drill holes in the tang.

Step 6: Quench the Blade

I heat the blade until it is non-magnetic, let the heat build a little more then quench in oil.

The blade goes through a temper cycle then I continue with final grinding of the blade. The bolster is finished with a file to ensure square shoulders and good fitting of the handle.

Step 7: Attaching Handle

I prepare some stabilized timber and drill holes through it using the tang as a template. The handle scales are epoxied onto the blade and allowed to dry overnight.

Step 8: Shaping the Handle

My aim for the handle is to contour it and have it smooth in the users hand. This takes patience and fine adjustments until I am satisfied the handle is silky smooth.

Step 9: Etching My Logo, Etching the Blade

Until this point, the blade has been shiny but the underlying patterning of the forged blade is mostly unseen.

The blade is cleaned with acetone then allowed to sit in a solution of ferric chloride until the pattern is seen. Beautiful!

Step 10: The Completed Blade

The completed knife feels good in the hand and the blade patterning is complemented by the light colored timber handle.

I hope you have enjoyed this project.

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    19 Discussions

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    zakbobdop

    2 days ago

    This knife has definitely spoken for itself ;D Great job!

    1 reply
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    liquidhandwash

    8 days ago

    That is cool thanks for sharing. I tried to make a billet from spokes about a year ago and failed miserably. I cut a chrome-moly tube off the bike and stuffed it full of spokes, I proably should have cleaned the spokes first.

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    The can method of forging spokes (and using the bicycle frame) is a brilliant idea. Maybe it wasn't hot enough? Or the alloy in the spokes stopped them welding properly? I was lucky that the spokes I had available welded together well. Thanks for sharing your story.

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    DickM11

    4 days ago

    Wow, thanks, this reminds me of an article I read about the Sutton Hoo Sword which was pattern welded using twisted iron rods. A replica was made with difficulty and the patterning on the blade is glorious.

    1 reply
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    Minnear KnivesDickM11

    Reply 2 days ago

    I didn't know about the Sutton Hoo Sword...it's a fascinating blade!

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    lclaiborne

    3 days ago

    Spokes come in many different alloys. You can just buy the better ones, they’re used to hand build high end wheels. Having spent years riding such wheels, the spokes would make one heckuva knife! Fabulously resilient metals.

    1 reply
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    lclaibornernshagam

    Reply 3 days ago

    Spokes aren’t chrome plated. Cheap ones like these can have a laquer or plastic dip to protect from corrosion. Chrome playing spikes adds a lot of money and weight, only a low rider show bike would be bothered, and it’s custom work.

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    bpark1000rnshagam

    Reply 4 days ago

    I say the fumes are from zinc or cadmium, not chromium. Many spokes are galvanized, which is a coating of zinc to inhibit corrosion. The zinc/cadmium boils off and then oxidizes, giving zinc oxide dust. Chromium's melting/boiling points are similar to iron, so I can't imagine chromium fuming off. The same goes for manganese or vanadium, which may be alloyed in the steel.

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    ironsmiter

    8 days ago

    You likely could disassemble, case harden, and return to active service.
    A good case hardening may not last the "lifetime of the blade" but should
    give a good decade, unless in the hands of a professional chef.

    One thing I've always wondered. Why mark substandard product?
    I've only ever used my touchmark (or engraving) on products I am proud of.
    Even in ceramics, I would rather engrave my mark later, if I thought the
    fired piece may not come out to my satisfaction. Sure, I've made plenty of
    utility grade stuff, and it is OK, and I even tell people I made it. But to receive
    my mark, it has to meet my expectations.
    I suppose, I have see plenty of examples of markings that are struck out later.
    For instance, grey market knife blade kits supplied with factory second blades
    that have their marks struck out. That would probably be better than what I've done.

    2 replies
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    Minnear Knivesironsmiter

    Reply 7 days ago

    Thanks for your comments. I added my mark because I am proud of the knife and the workmanship I put into it and because the pattern is so unique.

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    RobertN124

    6 days ago

    Beautiful work and really quite a unique medium to use. I would have never even thought of forging spokes of a wheel. Great job.

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    pstolle

    6 days ago

    You can also use the wires at the edge of the tires, it is very tough steel. Somewhere there is a guy on youtube he called it Damascus steel. Interesting methode.

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    DanPro

    7 days ago

    Beautiful job! Your previous knife Instructable is also quite impressive. I would love to have either displayed in my kitchen.

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    joen

    8 days ago

    It's sad that this knife won't be used for its intended service. It is still a beautiful knife. I hope there are other ways to put this knife in service.

    1 reply
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    Minnear Knivesjoen

    Reply 7 days ago

    Thanks for your comments. I'll be using the knife in my domestic kitchen, and I'm expecting it should perform ok. I'll keep an eye on the sharpening requirements as I go...it could perform better than I expected.