Forge welding hammer

[Shabumi]

I remember a while ago seeing a thread on forge welding that describes the type of strike used for forge welding. I'm paraphrasing, but I believe it was "light, sure hits, with minimal rebound."  Then yesterday someone described to me how a dead blow hammer works. "Same amount of force goes into the hit, but the filling spreads out the length(time) of impact, reducing rebound". So my question is, would an all metal dead blow hammer be a useful tool for forge welding?

Please correct me if I'm wrong on either description, or if my idea of 1 and 1 don't equal 2

[ThomasPowers]

Probably; but the deadness of the blow would also slow down multiple hits and most billets I work on need several quick blows down their length to weld more than just 1 hammer face's worth.  

Might make an interesting experiment to try; of course some experience with using both types of hammers would be needed for comparisons.

[JHCC]

Also, most dead-blow hammers have urethane faces, so you'd need one with a steel face for the higher temperatures of welding.

 

[Frosty]

We're talking adverb vs. adjective here. A "dead blow" with a hammer is different from a "dead blow hammer." Striking a dead blow means the person striking the blow is hitting the work in such a way as the hammer stops DEAD on the work and minimizing recoil off the work. A heavy hammer and low velocity delivery is a short set of instructions for HOW to perform a dead blow.

A "Dead Blow" hammer is a hammer that delivers a dead blow but isn't used blacksmithing a second time. As described above a dead blow hammer usually has different soft faces that absorb the impact shock typically delivered by a hammer and can cause damage to objects. Say driving bearings into races or races into receivers. You want the force but not the shock so you isolate the part from the shock. Old days mechanicing we'd put a piece of wood between the target and hammer to take the shock and deliver the force.

Make sense?

There ARE however dead blow hammers that would probably be adequate for performing forge welds but I've never use one welding. This type would be a "lead shot filled" steel dead blow hammer. I haven't seen one in a long time but they're out there. The hammers in the automatic power hammers on the drill rig were filled with powdered lead. The casing and penetrometer hammer weighed 340 lbs. with a required 30" free fall and the 140 lb. weight t drive 1" - 2" split spoon samplers also required the 30" free fall. both hammers were intended to simulate pile driver hammers for the purposes of soil tests and replaced safety hammers witch were operated with rope and cat head by the driller and less consistent. 

Anyway, in short when doing a forge weld YOU want to perform a dead blow, hit the weld with as little rebound as possible. As opposed to a hammer that delivers as little shock as possible and avoids shock damage to the target.

Frosty The Lucky.

[ThomasPowers]

JHCC: I think he covered that in "So my question is, would an all metal dead blow hammer be a useful tool for forge welding?"

[Frosty]

Should be easy enough to make one and find out. No? Myself I just make the blow as dead as I can and I get decent results, not as good as blacksmiths who practice for a living have been getting since beginning of the iron age. I do alright though.

Dad used to discourage trying to make or use a tool or machine that takes the place of the skill of the person. 

It's still darned attractive though. A lead shot filled hammer head shouldn't be a problem. Pipe: welded face, screw on cap on the other end, done deal. A handle of course but that's a detail. The IMPORTANT trick is to make sure the lead shot is sealed in so dust can't escape. 

There are other possibilities of course, say stack lead disks in the head..

Weight good, elastic recoil BAD.

Frosty The Lucky.

[anvil]

22 hours ago, Shabumi said:

but I believe it was "light, sure hits, with minimal rebound." 

Well, to me this is a redundant question. Mainly because rebound is only truly a factor when you strike or drop your hammer onto the face of the anvil.

Try this. Just let your hammer freely drop onto the face of the anvil and note the rebound. Next do the same onto a cold piece of iron laying on your anvil face, say a hand held piece of half square. Finally bring that piece of half up to forge welding heat and, again, drop your hammer onto it. I think you will find that the latter two have minimal rebound and the third, at a forge welding heat has the less, if any rebound. So you see, rebound is not a factor in your forge weld or for any forging of hot iron on your anvil. Rebound tells you two things, depending on your anvil type. It indicates the hardness of your anvil surface and it indicates the quality of the forge weld holding the tool steel face to the wrought body.

Thomas, in the second post nailed it, so to speak, when he said you need a bit of experience with both types of hammers to test this.

I suspect that when you have the experience with your daily driver hammer to confidently be able to make a good forge weld, there will be no need to test further.

The typical dead blow hammer is a cast hammer out of lead. I wouldn't try this on a forge weld. I have no idea what a steel tube full of bb's would do. Lol, 

In fact I've not had a use for a dead blow hammer in my shop for a long time. Not that I haven't tried. I've cast lead and copper ones, used brass and wood as well. Their primary use is straightening iron and not leaving any marks, not forging hot iron. I've replaced these long ago with far better, in my opinion,ways of straightening iron.

However, give it a try and let us know the results.  

[Shabumi]

2 hours ago, Frosty said:

This type would be a "lead shot filled" steel dead blow hammer.

The one that I saw that got my brain juices flowing was home made wooden, sand filled hammer. Before he retired, my friend used them to, among other things, set wooden dowel "nails" into his all wooden constructed custom bridges without damaging them. He didn't trust the new fangled rubber faced ones. He doesn't work metal, but he understands how things should work and when I described my understanding of the forge welding process, and my successes and failures in welding, he suggested a dead blow hammer may help. I figured I'd ask those who do work metal what their opinions would be. Perhaps I'll take a short length of ¾" pipe with male treads on both ends, fill most of the way with sand, cap it and attach a handle somehow to make a prototype to see if there is any validity to this theory. I doubt it will be a substitute for hammer control, but it may be a nice little cheat. Or not. 

Thank you everyone for your input and additional info on the subject.

I know asking a woodworker about forge welding is like asking a skydiver how to mine for gold, but conversations tend to take their own path when potent potables are present

My current welding skills are limited to 3 chain links that held and a couple poorly formed animal heads, so as of yet I don't need anything bigger than a hammers face to weld

And yes, I agree with all of you, no single tool can take the place of a properly honed skill, which will be practiced as often as I can

 

Edited October 24, 2019 by Shabumi
Added a few lines

[bigfootnampa]

1 hour ago, anvil said:

So you see, rebound is not a factor in your forge weld or for any forging of hot iron on your anvil.

This is inaccurate.  The anvil’s rebound quality will determine the opposing force to the hammer’s blow.  With an anvil that has better rebound more work will be done with each hammer strike.  Over thousands of hammer strikes, this will have a big effect on the efficiency of your forging.  This is why rebound is such a critical quality in selecting an anvil.  It’s not about bouncing the hammer... the force is transferred to the anvil side of the forging blank.  When an anvil has less rebound... more of the forces are wasted in heating and deforming the anvil... to no useful end.

[Frosty]

Shabumi: It is a good question and a contribution to the forum. Sand will make a fine dead blow hammer, just not as massive as lead shot. I'd use something larger than 3/4" pipe, significantly, say 1 1/2" - 2" dia. Not so much for the greater mass as much as larger striking face. You want to push the weld together, not make dents.  If you know a  mason or supplier see if s/he'll let you have Rhyolite sand, it's more massive than silica sands. That'd be tickling nits though. . . Nevermind.

Adding oil will add mass and not effect the deadening qualities.

Frosty The Lucky.

[ThomasPowers]

Hmm shot blasting medium or powdered metal would weigh a bit more than sand and be less toxic than lead.

[anvil]

17 hours ago, bigfootnampa said:

This is inaccurate

I don't want to go off topic, so a quick response. this has been debated many times. Some believe like you, some like me. Instead of a long rambling reply and the proverbial 10 pages of arguement, I'm  going to suggest that you do the test I suggested. drop your ball bearing, or hammer and measure the rebound. Then bring a piece of half square long enough to hand hold to a good forging heat. I suggest a good yellow. Drop your ball bearing and measure the rebound. It will prolly be close to zero. Do this on as many varied anvils as you can find. The rebound may be different depending on material, but the end results will be the same. End of the test. 

On 10/23/2019 at 4:31 PM, Shabumi said:

Please correct me if I'm wrong on either description, or if my idea of 1 and 1 don't equal 2

For what it's worth I'm answering his question. It's always a hard decision to not be encouraging to test your ideas vs indicating that there is no need to reinvent the wheel. Please, no offense meant to anyone.

So, let's assume it's a valid experiment and go for it. We need to decide our tools and consider all positives and negatives. Frosty nailed it. What size hammer? A 2-1\2# hammer is a good average weight for a working hammer. What material should be used? 1" gas pipe is seamless and prethreaded. there are threaded caps for this type of pipe. I believe they are cast but may be drop forged, I'm not sure. My hammer measures 1-3\4" on the diamond and about 1-1/2" on the flat. So you can have a very tall skinny diameter or a normal 4" with larger diameter pipe. Next which is best? heavy wall?Thin wall pipe? Threaded ends or welded?What is a good filler? Plenty of good suggestions and I'll add another. I think the canister Damascus guys use powdered iron from the garden stores. This is a good possibility. Being Iron, it has a higher density than what's been measured. I suggest welded not threaded end caps.

So now we have a hammer setup. So let's look at potential problems. So far the container is some semblance of mild steel. What's going to happen when we strike a forge weld? Well, there is a reason our hammers are heat treated. Primarily to keep them from distorting. How many blows will it take to screw the threads if threaded? How many hammer blows till the face and or sides become distorted if welded? Not many, I suspect. 

Now the final question. I stated above that rebound of the hammer is dealt with by learning proper hammer control. Also, hammer control is what keeps the two pieces from springing apart. Quite simply, if you hit it too hard the pieces will spring apart. 

So, now that our hammer is made and we recognize the possible problems, all that's left is to learn proper hammer control with this new hammer in order to strike our forge weld with the proper force in order to make our weld. This is a must no matter what hammer or what it is made of. Thus, in either case the success of your forge weld boils down to proper hammer control.

With all due respect, there are no cheats in our craft, no training wheels. This is not forged in fire or a computer game. Hammer control beats all.

And that's why I suggest that you just learn the needed hammer control with your daily driver to make a forge weld.

No matter your choice,,, have fun.

[Shabumi]

14 hours ago, anvil said:

 Well, there is a reason our hammers are heat treated. Primarily to keep them from distorting.

This is true for a hammer that is used to deform metal, but I thought the goal when forge welding was to keep deformation to a minimum until the weld was set. A softer hammer would cause less deformation to the piece being welded.

14 hours ago, anvil said:

With all due respect, there are no cheats in our craft, no training wheels.

 I do appreciate you playing devil's advocate in this conversation, and you do bring up quite a few questions I hadn't thought of that require consideration, but I would have to respectfully disagree with this statement. In my short time that I've been in this craft, I've seen many cheats. Guillotine tools are a way to have a top and bottom tool aligned and ready, cheating the need for a third arm, or striker. A band saw instead of using a  chisel. Pritchel hold down tools, scroll forms, bending jigs.  Even the Hardy hole is a cheat to hold a tool on the anvil, a cheat that has become standard, but a cheat none the less. None of those tools are required to do their intended jobs, but they do tend to make those jobs easier, which is why people use them

Perhaps I shouldn't have used the word "cheat", maybe "hack" or "innovation" would suit better.

I'm not looking for the magic hammer that will set every weld with one blow, but if there is a tool that can increase the likelyhood and consistency of making the metal do what I want, then I'll be happy to take all the help it'll give.

 

[Marc1]

If rebound had any value, welding with a press should be very difficult. 

[pnut]

You can weld with only pressure.

Pnut

[anvil]

8 hours ago, Shabumi said:

but I would have to respectfully disagree with this statement. In my short time that I've been in this craft, I've seen many cheats

no matter your time in this craft, you have not named any cheats, nor have you listed any innovations or hacks.

What you have done is make a subjective value judgment based on nothing  more than your assumptions and experience level. No fact, no definition, and to repeat,,, just your assumptions based on your experience level.

For what it's worth, lol, I'm pretty much a traditional smith at every level. and I've made a good living doing it. However to make it clear, the tooling you use has nothing to do with the esthit you want to create. I don't care if you use a torch, welder or side grinder. Tools will attempt to demand a certain usage and this will create it's own esthetic. However if you are able to not get locked into what te tool demands, but use it for whatever your reason and have it enhance your own personal esthetic, then that's the proper tool for the job at hand.  contrary to this, if you can't, then don't use the truth. Here's an example. perhaps you have a piece of half square that wont quite fit, it's a bit too big. There are many solutions. Let's look at a side grinder to solve this. you remove a bit of material and remove the beautiful forged finish you have created to match your own esthetic. If you can't  restore that forged finish, then that tool is forcing it's own esthetic on you. And it will be an obvious fault. If you can, then that tool is the proper tool for that job and it is NOT a cheat, a shortcut, an innovation or a hack.

Now back  on topic. 

On 10/25/2019 at 10:06 AM, anvil said:

Thus, in either case the success of your forge weld boils down to proper hammer control.

End of story.

[Shabumi]

Ok. Uncle. You win. The traditional smith who uses an electric welder and angle grinders has brow beat the inquiring mind into submission. I have seen others with a better way with words than me argue with you, only to find it an exercise in futility. 

21 hours ago, Marc1 said:

If rebound had any value, welding with a press should be very difficult.

The press would be a better way for me to go if i had the means. To my understanding the lack of rebound is one of the things that makes the press a better option for forge welding. It basically being a heavy hammer with a slow velocity, the same definition frosty gives on the fourth post of a dead blow

[Marc1]

Yes, press is good for damascus or welding, much more controlled than a hammer. dead or alive. 

The idea of a dead blow ... more semantics than anything else ... is to achieve a stroke that goes all in the work and were nothing bounces back due to elastic forces. 

A hammer that has some plasticity to it, be it lead, titanium pellets or what have you, will most likely achieve that,As for the difference between this hypothetical dead blow, and an actual hammer blow with an ordinary rounding hammer or similar ... who knows if there is any. A bit like the anvil rebound d d d. Oops, I missed and hit the anvil

[anvil]

Dang it, Marc, snorted coffee on that one! 

[Shabumi]

Had a buddy weld a couple of pieces of normalized? (heated to red to straighten then air cooled) 3/8 inch leaf spring onto an old ~2.5 inch od pipe, filled 3/4 full with the finest quartz sand I could find in the hydraulic mining "Diggins" behind my house. I got to try welding on the handle, its not pretty but he said it should hold. He's just a backyard welder, so I'm not sure if his opinion is worth much on this subject. I'm in the process of grinding it down to check for cracks and to make it a little prettier. It's about as heavy as my 3lb hammer, maybe a little more.

I did try it on a longhorn I was trying out and I "felt" the weld on the first hit. I hit it again for good measure and it felt solid, so I figured I'd go with it. It was probably a lucky hit more than the hammer, as I've only ever felt the weld once before. More experiments to come.