My original 60 grade rebar article has been very popular because it covers the general questions on rebar from a field testing stand point however it largely has left out the more commonly found 40 grade, so I decided to tackle it head on in this update to REBAR: HOW AND WHY.

 

The 2 daggers above were forged from a single piece of random grade 40 domestic rebar. I decided to  torture test the hardness, strength and consistency of grade 40 after the success with grade 60. The results were 100% positive in the fact that this material water hardened so well I myself could not believe it. I made 2 daggers out of it with identical results and then quench hardened a non worked portion to test randomly in my vice. I place the round undeformed piece in my vice and attached a wrench to it  attempting to bend it. It was so hard that not only did it barely bend under pressure it actually return to shape when it finally did flex.  After this testing it still appears that tempering is not 100% needed  but this is my own preference. Viewing my  experiments in whole I have yet to have any negative result from making blades out of either 40 or 60 grade and the hardening ability/carbon has been high in all pieces I have tested and all tests have been on totally random pieces. One piece actually snapped when I continued to forge below temp.

 

My steel rating:

Workability: A+

Hardening: B+

Durability: A+

 

I again highly recommend at least testing this your self and seeing if you get the same results.

I will be making a rebar Scandi and it will be featured in a future article with testing data.

 

Remember that field testing material has far more value than internet myth and metal working lore that up to this point has been flat-out wrong.