Jump to content
I Forge Iron

New blacksmith - semi-leaf springs


Recommended Posts

Greetings IForgeIron friends. I'm new to blacksmithing and but I've been lurking on the forums here for about a year now and learned a lot from you guys, so thanks! But I've come across an issue and I'm not sure what is wrong. So I found it is time for me to join in, and hopefully some one will impart their wisdom upon me. I've got most of my shop put together, I built myself a propane forge, I've got a decent starting anvil. I've managed to do several small projects with smaller metals and things like RR spikes. Recently though I acquired a leaf spring from a semi trailer. I cut a few pieces off with torch. My main goal was to just draw the pieces out first into something of workable size. But much to my chagrin they are incredibly resistant to my attempts. I'm using a 2.5lb hammer (which my only guess is I might just need to get a bigger one) but after heating it to white hot and pounding on it I'm barely putting a dent in it. Am I just a wimp and need to grow my beard out more? Thanks again for any advice!

 

 

Link to comment
Share on other sites

Yes the alloy steels are a lot more resistant to hammering---some of them will just laugh at you when you hit them with a sledge.  How large is your anvil?  Is it mounted securely?  Can you get someone to hold the piece while you hit it with the proverbial bigger hammer?

(I used to smith in Fort Smith but now I'm a borderline case...)

Link to comment
Share on other sites

I think my Anvil is 125# (It came mounted to a heavy duty iron pole welded to a truck wheel and all the writing has rubbed off) so it is mounted securely. I could probably grab some one and get a sledge, but at the moment it would probably just be easier to get the metal I can solo work.

(Small world! I know there is a lot of smiths up in NWA but I haven't run into any here in the Fort yet)

Link to comment
Share on other sites

Looking at some high temp derating information for tensile strength on some materials---unfortunately not a data format that is useful regarding forging but just to give a rough idea of the difference:  At 1400F, the difference in listed working tension (not true yield or anything statistical) from lowest to highest on the list is 700 %...at 1800 that drops to a difference of about 100%.  What that tells me is that you have to work em hot or the difference can feel HUGE.  Even a little cold and the hard ones will be far harder to move.

Some of the lesser materials without all the good herbs & spices in the mix just drop off the list at those higher temps because they get so soft---That's one reason the chart isn't worth getting into specific detail on.  Plus I doubt anyone here is forging Inconel.

 

Link to comment
Share on other sites

The key to forging is to not forge when you don't need to.  Save that thick leaf spring for when you need thick stock.  By the time you get it "reshaped" into something that you need, you could have more easily purchased new stock in the size you wanted in the first place.  Burning up $100 in fuel and labor just to end up with a bar that costs $10 brand new... well, not the best way to go about things.

 

Link to comment
Share on other sites

Not sure but If I may offer a suggestion.   I've worked those springs and found that they respond better with a long preheat before ramping up to forging temperature. 

That's good advice.  :huh:

The "color" you see, is only an indication of the temperature on the surface of the piece.

The other advice given above, ... ( ie: start with material as close to the finished size as possible ) ... is equally sound.

 

With experience, you'll come to understand that many of the things that you can do, ... are not necessarily the things that you should do.  :P

 

.

Link to comment
Share on other sites

I concur with Charlotte/Smoothbore. Need to make sure its heated deep too.

I'm kind of the poster child for doing stuff the hard way. I've split many heavy truck springs to make chisels/fullers vs waiting to acquire something closer to finished size. Often enough I think one might call it customary for me to do so. 

Advantage in making thick bars into skinny bars often is, at least IMO, it's the best way to develop hammer control while you're still learning, especially when you're just making chisels/punches. On the other hand, you don't want to burn all the carbon out trying to prove who's tougher either. 

Link to comment
Share on other sites

I am novice also. i'm currently pounding out a large roller bearing between small projects. Big hammer, my big kid swinging 8lbs, and long deep heats have it just starting to upset. I think the first portion of upset leaves very little impression in high carbon steel. . But as we continued it has begun to 'grow'in length and seems to become more maleable. Even the sound of the hammer strike sounds softer now, it still is moving slow. I think the long deep heats are important to creating that plasticity in that hard  metal. We add the bearing to our fire edge as we play with our small peices and as the day progresses move it in to just on top of the oxidising layer,  till you can see the inside dance yellow with color..then we hit it equal times on all sides. My round roller is square now and just starting to lengthen...Somewere in my future I will build a power hammer to end this madness.

 

Link to comment
Share on other sites

I have read that you may need to anneal metal like that before forging.  That old leaf spring has been hardened, tempered and toughened though work.  My suggestion is to anneal the piece before attempting to forge it.  Get a metal bucket full of dry ash, clean kitty litter, or vermiculite and heat your metal to bright yellow hot and cover it well in the bucket.  Let it cool slowly over 24 hours.  You can do this with several pieces at once.  After 24 hours you should be able to file it easily.  Then heat it and see if that makes a difference.  

By annealing the leaf spring you will alter the structure of the steel molecules and renew the ability to forge it. I have done this with D2 and Chipper steel that were used in a wood chipper.  Once the steel was annealed it was much easier to forge.  

Good luck.

Link to comment
Share on other sites

Solutioning the carbides can change how it forges which may be a byproduct of your annealing   How did you anneal D2 as I recall it takes a programmable furnace. 

Well, I didn't have a furnace to do all the heats and cool downs at different temps to properly anneal the Chipper and D2.  I just did it as best as I could.  I heated it up, let it soak for 5-10 minutes without burning it and put it in dry coal ashes to insulate it while it cooled down slowly.  I noticed that helped for forging and grinding. This method also helped when drilling holes in tangs.  It is still tough but seemed to be much better after the treatment.   I did this both for Chipper and D2 wood chipper blades.   That was 20 years ago, but as a recall, I would occasionally heat a few chipper blades in my forge at the end of the day and then let the blades cool in the hot fire as the ashes cooled down.  I don't recall what worked best though, the insulating ashes or the cool down in the forge.  

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...