Treadle hammer mechanics?

[JHCC]

15 minutes ago, jlpservicesinc said:

Its the human condition that our bodies only move a certain way..  legs for the most part are up and down with circular thrown in..

In addition to which, the leg muscles are some of the strongest in the body and therefore are capable of putting the most power into a human-powered hitting machine.

If there were some way to hook a treadle hammer up to a uterus, all our problems would be solved!

[jlpservicesinc]

Whoo there JHCC...   Family drama???   The Uterus has nothing to do with marital instability. or other domestic situations.   You guys simple don't listen to what is being said.. LOL..

[Daswulf]

 when I don't listen I get sent to the garage! No wonder I'm deaf. 

[Charles R. Stevens]

I think is just envy, Jennifer. Any muscle that can be so stretched out of shape, contract for a day and a half trying to expel a bowling ball sized parasite is to be admired. 

[jlpservicesinc]

Oh, I get it..  JHCC..   I miss understood...  I couldn't imagine the implications of having a treadle/kick pedal attatched other than being completely uncomfortable.. LOL.  I get it now.  

 

Sorry aobut that.. It only took a few of you to make me see the light.. Thanks.. 

Charles, crazy right..  And then to be able to walk, eat and other things normally again.. LOL..   It's an amazing machine the human body.. 

[JHCC]

2 hours ago, Charles R. Stevens said:

I think is just envy, Jennifer. Any muscle that can be so stretched out of shape, contract for a day and a half trying to expel a bowling ball sized parasite is to be admired. 

Yes, the uterus is THE strongest muscle in the human body. I’m not envious, but I am in awe!

[MilwaukeeJon]

On 4/23/2018 at 8:24 AM, MilwaukeeJon said:

Fascinating info in this thread.

Just curious: for light work, have folks ever reversed the principle and simple taken a big sledge (20lbs or more), created a pivot point at the back of the handle and with a leg lever/pulley system simply lifted the head to drop it on the anvil? I realize you lose a lot of added leg power that comes from contributing to the downward force on a regular treadle hammer but would the notion of a leg-powered drop sledge have any merit or would even a 20lb sledge being dropped 10-12” inches not create any sort of useful forging power? 

* I’m an Art History major so my understanding of Physics and the like is non-existent! 

 

Quoted here is my earlier post from this thread and I appreciate all the insightful responses. Just for fun I'm going to make this leg powered sledge hammer. It unquestionably is crude, inefficient, stupid, probably an all around lousy idea....nevertheless I feel like giving it a go just out of stubborn curiosity. Here is a sketch: 

 

 

Any thoughts on what the bottom anvil should be? The sledge presumably is pretty hard steel. I have a striking anvil that is pretty soft faced but should I go with something different? What kind of weight/size should this bottom anvil be and what kind of stand/stump should it be on? 

Other design thoughts that I need to take into account? There will be an iron sleeve on the pivot end of the sledge handle for reinforcement. 

Again, I realize this is a goofy concept but I'm not inclined to make a treadle hammer and don't want a power hammer (I don't do heavy work). I'm also dealing with some rather feisty tendonitis, so this might help my elbows a bit. Thanks in advance. 

[JHCC]

If you persist in pursuing this folly, you might consider positioning the hammer both so that it hits where you want and can simply be swung up and out of the way when not in use. 

[MilwaukeeJon]

I'm not going to use this on my good anvil (1901 French pig), so another bottom anvil option is needed. Should I get a cheapo Chinese cast anvil or should the bottom striking plate/anvil be higher quality steel? 

[JHCC]

A cheap cast anvil with poor rebound would make an ineffective setup even more so. 

[jlpservicesinc]

Been there and done that..   It was terrible...  the losses with the rope were ridiculous.. I eventually tried it with chain and special pulleys..  it was only marginally better.. 

I then tried a wooden spring board arrangement with a heavy head. the wooden plank acted as the spring.. . It was well not good....  The swing of the hammer wasn't great enough to really have a wallop. 

If you have fabrication skills, Making a foot hammer is fairly easy..  or you could make a treadle hammer.. 

[JHCC]

My welding and fabrication skills are minimal, and I was able bust out this bad boy out of scrap, donated springs and lead, and some industrial surplus. It has completely changed what I can do in the forge. 

 

When I’m not using it, I disconnect the treadle chain and the springs pull the head up and out of the way of my ~1835 Mousehole, allowing me to switch back and forth from hand work to treadle work almost effortlessly.

(Sorry for the poor picture quality.)

[MilwaukeeJon]

No fabrication skills. 

Was thinking of a wound wire cord (1/8” I think) for the “rope”. I’m lifting and dropping the weight with the foot lever so does the wire chord suffice?

[JHCC]

Doesn’t matter; there is an absolute hard limit to the amount of force that your design will produce, and that’s the force created by a 20lb weight falling about a foot. You’ll get more striking force with a heavy hand hammer. 

[MilwaukeeJon]

JHCC, that certainly is true....but I'm still curious. Sure as heck wouldn't want to drop that big sledge on my toe from 12" up so it might do something to some really hot steel.

 

My work is just for fun and is pretty small scale (small headed hammers, knives, etc). Maybe this gizmo will do something useful. If not, I'll definitely report back on the nature of the failure, which as with my many past failures will teach this newcomer some valuable lessons. All good!

[MilwaukeeJon]

I will, prior to building, try out the power of dropping this 20lb sledge from 12"-15" (with no added force) on some hot steel this weekend. Photographs to come....

[Frosty]

Jon: When you drop the 20lb. from 12" for a test, do it from 8" instead, the rope, pully and lifting the board will suck at LEAST that much energy from it.

Try this instead. #1, use a good quality gate hinge for the hammer pivot on the wall and screw it into a stud. Yes? #2. Forget the pully and rope, cable is even worse it's less flexible and sill suck up more power. Okay, no pully & cable. Mount a gate, etc. door spring to the same stud as the pivot, approx a 30 lb. tension spring should do nicely. 

Lastly mount the treadle in line to the floor, NOT the wall. Using what you like, cable, chain rope, old leash, solid rod, etc. Connect the hammer to the treadle. Do it while the hammer is resting on a spacer a couple inches above the anvil face if using a soft connection, chain, rope, etc. If you use a solid rod connect it with the hammer just off the face. While the treadle is resting on the floor. 

That means the treadle bottoms out slightly ahead of the hammer. A soft connection lets you snap the hammer and not keep stomping the ground. If you use a solid connection the ends will need to pivot, yes? You can snap the solid connection and let the hammer carry the treadle to the floor. A solid connection will add the weight of the treadle to the blow but it's not significant so don't get excited.

You can adjust travel distance and speed by where you connect the  treadle and hammer handle. If you tie the treadle close to the foot pad and close to the hammer head you'll have to move your foot the full length of the stroke. Yes? Now, if you connect the treadle half way to the pivot and close to the hammer head it'll be easier to push but you'll only get half the stroke.  If you connect close to the foot pad and close to the pivot on the hammer handle it'll be harder to push but you'll only have to push the treadle a fraction as far and it'll really snap the hammer down fast.

Make sense? Don't hesitate to model these things with popsicle sticks or an erector set.  I've connected pencils with rubber bands, often just what was handy.

Frosty The Lucky.

[MilwaukeeJon]

Fantastic! I’m a bit confused by the wall/gate hinge mechanism. Is the wall stud vertical? If so is the spring attached high on this stud and then also partway up the handle to keep it elevated? Thanks in advance. 

 

[Frosty]

Yes. Studs are the vertical structural lumber in the wall. Use wood screws to attach the hinge and spring hook. Go look at a gate hinge, There's the barrel which holds a pin, it's the part the hinge turns on. Attached to the barrel are two bolt plates, usually one short and one long but there are hinges with two long sides one of those would be the better choice for a treadle hammer pivot. If not, the long half screws to the underside of the hammer handle. Pre-drill THESES holes! You can get away with just running screws into framing lumber. . . .usually but NOT into kiln dried hickory. Ask the person at the hardware store to tell you what size drill bit to use, that's pretty important but I won't go into why it'd just confuse you without good reason.

Draw a vertical line in pencil on the wall so you can get the hinge aligned properly this is important too.

Making sense? 

Yes, the spring is the return that holds the hammer up but allows you to push it down to strike and returns it for the next one. The Spring hook on the wall need to be a good sized one it needs to be strong ad you have to install it centered on the hinge so everything swings straight. Yes? Pre-drill the hammer handle for the "eye bolt". You want a closed loop on the hammer it bounces around a lot and the spring may jump off a hook. Heck use an eye screw on the wall too.

I think that's enough for now, we can talk about the treadle if you need later. Just be sure it's in line with the center of the hinge and spring.

Give a shout if you can't figure things out but I expect you to think for a while first, you need to know how to figure things out. Okay?

Frosty The Lucky.

[MilwaukeeJon]

Thanks much Frosty. Regarding studs, I do know what they are. I was talking specifically about adding an external reinforcing stud on the outside of the wall (in drawing) but probably not needed. Will play around with this design a bit and I appreciate your helpful input. As for the hinge for the handle an old-style blanket chest hinge with equal 8-10” long plates would possibly work nicely. 

And I think I can handle the screw hole dimensioning and not get too confused.......have been building furniture with traditional hand tools for a long time now. Just very new to smithing as well as any sort of metal fabricating and machine making. 

[JHCC]

Lovely. 

One good option for springs is the counterbalance spring off a garage door. A repairman near me gave me half a dozen old ones that he’d replaced:

[MilwaukeeJon]

Great idea. I need to keep messing around with drawings. The wall mounted spring could cause some bodily harm if the hook end let go and flew back at me!

In theory, and again this is just playing around with the mechanical concept and not necessarily logical or practical at all, would a kind of “see-saw” logic work for a hammer of this sort....with a nearly central balance or pivot point and a rear spring between the extended (think twice the normal length) sledge handle and the floor? This of course makes use of the basic fulcrum idea, and would include a sledge on the end of the “effort arm” and a spring under the “resistance arm”:

 

 

And would one gain more power by sliding the sledge handle into a longer metal pipe (or “arm”) to gain more leverage? This could lead to the creation of a totally ridiculous looking 10’ or 15’ long see-saw hammer! 

 

By the way, some lids on historical American and European desks (1790-1840 or so) use internal L shaped interior brackets with heavy balls on one end that act almost like a hidden sash weight, helping the lid open and close more gracefully.

[JHCC]

Remember that garage door springs come in two varieties: tension and torsion. You want tension.

[MilwaukeeJon]

Thanks. I did not know that.

[Glenn]

You may want to look at the Oliver hammer here or

the Oliver hammer on IForgeIron