Jump to content
I Forge Iron

Anvil rebound


Recommended Posts

I have a question about the rebound factor of various anvils in general. I do a fair amount of reading regarding blacksmithing and it keeps coming up about this "rebound" factor of anvils, which ones do and which ones don't. Now I have mentioned in past postings about my Star 155lb anvil that is cast iron with a welded steel top plate, well over a hundred years old and still going. I know that the solid steel anvils, cast or wrought are supposed to have the best rebound and ringing when you hit them. What I don't get is just how important this factor is. I have read that if an anvil has a poor rebound you will be " working against yourself " that the hammer lifts more than with with an anvil that does not. I would say my anvil rebounds to a degree but I have never worked on any others before and have nothing to compare it to. I don't see how there can be much of the hammer rebounding anyway as it is hitting hot steel that is soft? Mine seems to works just fine for me and thankfully does not have much ring to speak of either.
Thanks for any input..........Scott

Link to comment
Share on other sites

The hot steel is also being acted on by the anvil, not just by the hammer. If the anvil is soft then the energy is absorbed by both the anvil and the steel. With a hard anvil the work is absorbed by the steel, and "reflected" back to the steel by the anvil. Ring by itself is not important, as geometry and material choices affect that, and efforts to reduce it are often made. Ring is an indicator of the condition of the internal structure of the anvil. A broken anvil will sound dull or dead compared to an unbroken anvil of the same type.

Try an experiment: use a "dead" surface such as a paver on top of your anvil and make a small something, like a key fob or s-hook. Then use your anvil to make an identical item. Appreciate the difference.

I have used a paver to forge on once, made an exhaust hanger, and I have used a HF ASO for cold sheet metal work. My anvil is not great, it has broken edges and no heal even. The hardened layer is only about 3/16 deep, but it is much more lively surface than more primitive options. My anvil has similar rebound to RR track, but I only have a 4 inch piece of RR track from a thermite "weld" to compare to.

Phil

Link to comment
Share on other sites

Sheer mass has something to do with it also. Most anvils will not rebound at the horn or heel like they do in the center of the face directly over the waist. A 12" cube of mild steel will have a good deal of rebound even if the face is soft. However, a hard face on a soft body makes the best combination, which is why almost every anvil has this feature, either by a separate plate welded to the face or by surface hardening. This rebound effect will "throw" the hammer head back upon impact, which reduces the work the smith has to perform. This can vary with the quality of the weld and the hardening of the face so even a good brand like a Peter Wright will have variations from anvil to anvil. My 250 PW is pretty good but I worked on a 300 lb Haybudden a few years ago that was by far the best anvil I have ever struck - lots of rebound and the forging went quickly.

Link to comment
Share on other sites

I think that rebound from anvils is overrated. I have a 1" diameter hardened steel ball in my small toolbox, and it was really interesting to see what the rebound was from various anvils. A sledgehammer head has great rebound. My railroad rail anvil has poor rebound. My anvil with a weld repair shows poor rebound over the weld beads (probably 7018). But, the ball bearing bouncing does not forge steel. A 2.5 lb hammer, swung hard, does. And, I believe, as long as you do not deform the surface of the anvil, conservation of energy, and the fact that the coefficient of restitution of the hot metal is between 0.1 and 0.2, along with elastic deformation, if any, of the anvil face, leads to efficient forging. I dislike rebound anyway. I like to hit good hot yellow steel and watch the hammer sink in. If I hear any of that clank noise, that means back in the fire. One of the instructors in our workshop calls that "beginner noise". Of course, there is a lot more rebound with tool steel, but even that should be minimized. If the hammer is flying back up high, it means BACK IN THE FIRE!!!! Rebound, especially excessive rebound is not safe, particularly for beginners with ill fitting tongs. As long as the anvil and hammer are not getting marked, most of the energy is going into the metal, which is good.

But then, I heard of a smith injuring his shoulder from an anvil with insufficient rebound, so I am open to correction.

Link to comment
Share on other sites

im not sure if rebound is of detrimental importance. but the work hardened I-beam i used to work on was horrible and it had little to no rebound and was VERY loud. my 300# fisher on the other hand is quiet and has a fantastic rebound as far as im concerned. my big hammers have some rebound mabye an inch or so of "bounce". and the little hammers bounce like super balls. but i like the rebound i get because its predictable. and tells me whether im hitting square.

Link to comment
Share on other sites

pkrankow's explanation pretty well nailed it. Rebound is not a quality we desire in forging, it is just a way of measuring one quality of an anvil. Testing in this way gives a measure of the anvils qualities. Rebound is energy that should be returned to the forging, if your hammer is rebounding in forging then the energy is being returned to the hammer and you might need to re-heat.

Link to comment
Share on other sites

When material is struck at an appropriate heat should the forces applied.. considering the anvil is of good condition be transfered back through to the material, hence requiring less force?
If the rebound or anvils condition is of lower quality... are the initial forces applied dissapated.
The material is malleble at the proper heat and will absorb the blow but if the anvil, wheel say was made of feathers..fair enough it would become a stinky situation but because of a lack of resistance no impact on the material has been achieved.
Question: With a guillotine or butcher of radiused tooling say half inch top and bottom what surface of material when forged is impacted the most and why?
Sidesteer Michael.

Link to comment
Share on other sites

Even though high rebound has been a sign of a quality anvil for well over a hundred years, it might not be too noticeable between an anvil of lets say RC52 and RC59. To me the main difference is in the how the surface of the anvil holds up under the useage of the general blacksmith. With an anvil face of RC52, a square bar of mile steel (A36) pounded with a square corner down on the anvil, will more than likely put a small groove in the anvil face. That will not happen with an anvil with a deep hardened face of RC59 (Refflinghaus or Vaughans).

Even though it is not a good idea to pound cold iron on an anvil, many smiths do it as a final straightening etc. particularly when time is money.

Also, it is best from a safety standpoint to use hammers that are softer than the anvil. If the anvil is hard, it is easier to find softer hammers without having to use hammers that are too soft for most anything but hot iron usage.

Link to comment
Share on other sites

Anvils do make a difference both in size and in rebound.

My demo anvil is a 93# Arm and Hammer, (not vulcan!), and I sure can tell the difference between how tired I get doing the same exact projects on it and on my shop anvil a 500# Fisher.

If you don't have experience on various anvils it's really hard to say that the one you are using is the best one for you. I've read quite a few amazed wows from folks switching from a HF ASO to a HB, PW, Trenton, A&H, etc...

Link to comment
Share on other sites

My 2 cents on this. Only you can tell if the rebound is greater or more helpfull on a givin anvil. My thought is if I have to lift the hammer even 20% more X a 1000 hits thats too much. I am too old to lift more than I have to. I use a Hofi hammer with his vidio on a tool steel H-B. Works for me.
ken.

Link to comment
Share on other sites

Thanks to all of you for your responses and sorry for taking so long to respond myself. I have given each opinion much thought and came to the conclusion that I needed to experience other anvils to see where this would take me. So given I had been looking for a bigger anvil anyway, I put an ad in Craigslist for just that. Well before the day way over I had a call from a gentleman up north of me that sells all kinds of blacksmithing tools and claims he has over 40 anvils in his supply!!! and in the size I was looking for!!Well I had to see this so, off we went on Sunday for a two hour ride to find an anvil. He was not kiding..........lots of anvils and tons of other stuff crammed into a two car garage and everywhere else. First thing he did was hand me a hammer to tap on all those anvils. Check for rebound or any other thing you want to check he said........had the place ringing like a Church bell on Sunday.....ah, that's right is was Sunday, but you get my point. Anyway, the difference between these and my current anvil was incredible. Some of these anvils would bounce that hammer way back....... almost hit myself in the head on one when I did not expect it. The ring was rather painfull on most, not as I mentioned before, what I care much for but that's the way they are. Most were Peter Wrights and a few HB's. Well I walked away with a 230 lbs Peter Wright in great shape, big enough for what I do and much bigger than my other one. Have not had a chance to use it yet, it's sitting on my shop floor so I can look at it while I get a base ready. I could not be more pleased with this purchase and to have found such a gold mine with this person. I have his name and number if anyone wants it, email me at HawleysFW@aol.com I would be glad to pass it on. He is a rare find and a one of the nicest most honest people one will come across.
I will post pictures soon as she's on her base and ready to go.......
Thanks again for all the input, please keep it coming.......Scott

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...