Cam hammer

[paradox1559]

Has anyone here built/used a cam hammer? Aka a da Vinci hammer?  

I'm only having trouble wrapping my mind around how/what to make the cam. I've look through the archives and can't seem to find much on the topic. 

Sorry if its a dumb question 

[ThomasPowers]

Look at the old waterwheel driven tilt hammers and remember that Da vinci was not always the best way to go!  (examples can be found in "Ironworks on the Saugus" and "De Re Metallica" for renaissance versions.

[paradox1559]

Why isn't it always best? Was the concern speed or durability 

[ThomasPowers]

DaVinci didn't build most if any of his inventions; many of them didn't have the necessary technology base to actually work---bearings, precision.  If you don't build things and work the bugs out of them over iterations you don't have the best way to go.  Ever been advised to not buy the first year of production of a consumer item even nowadays? Do you know anything where the first try is still used centuries later?  Shoot even anvils were modified over the years.

[paradox1559]

Ok, so what kind of improvments can be made? I can't find any information on them. Im not looking to build railroads, just knives. 

Keep in mind I'm not going to build it out of wood 

[ThomasPowers]

Most of the modern DIY powerhammers would be much improved over a cam hammer.   SOFA has had a powerhammer building workshop before and they are close to you.

Personally I like the Tire Hammers.

If you are stuck on doing it all out of wood I would say spend the time mowing yards and buy a metal one and be way ahead of the process!

So have you looked at the ones in De Re Metallica yet?  I'd suggest also looking at the tilt hammers shown in the background of several different renaissance paintings titled "Venus at the forge of Vulcan"  

One SOFA member made a several hundred pound tilt hammer using a junked hay baler as the motive power and welded up an anvil with it.

[paradox1559]

I like the tilt hammer, seems simpler to modify. 

This is the first I'm hearing of De Re Metallica, ill need to find a copy, seems like a page turner. 

dam, I just had a junked MasseyFerguson square bailer, I was wondering if I could do something with the plunger.... Looking back there was a ton of useful stuff on there, and must kick my seat for scraping it.

[ThomasPowers]

Most books I mention can be easily ILL'd at public libraries in the USA

[paradox1559]

I'm gonna stop by my local library today, can you recommend others to check out? 

[ThomasPowers]

Can you state your "problem case" in a clear and complete manner so I can figure out which books would best suit it? I have several hundred books on various Medieval and Renaissance subjects going through the early 1900's and thing like selected ASM Handbooks up to modern books like Steve's book "Introduction to Knifemaking".  (Also redactions of medieval cookbooks, collections of down hearth cooking tools,  wood working, "Forgotten Crafts"  "Lost Country Life" etc and so on...)

For medieval and renaissance European technology there are primaries like Divers Arts, Pirotecnia, De Re Metallica and tertiaries like Cathedral Forge and Water Wheel, Mills of Medieval England, A world lit only by Fire/The Medieval Machine (as was said at a medieval technology conference I attended "One thought there was no technology during the late medieval/early renaissance time period and the other that there was too much!)  Mechanick Exercises has a "how to set up a smithy" as of the last half of the 1600's (published in 1703---be sure to get the complete edition and not just the subset ones only on printing...) "A History of Western Technology"  MIT Press was interesting to read---to me.  "Steelmaking before Bessemer, Vol 1 Blister Steel, Vol 2 Crucible Steel",  The Sword in Anglo-Saxon England, the Celtic Sword and of course the big dog on the block for Armour metallurgy would be "The Knight and the Blast Furnace"   "Metal Technology in Medieval India" had several interesting processes in it  (refining of Zinc and the decarburization of cast iron as I recall)  A Doctoral Thesis "Crucible Steel in Central Asia"....

For details on armour things like "Armour From the Battle of Wisby" of Heroic Armour of the Italian Renaissance .  ToMAR "Techniques of Medieval Armour Reproduction"

Sachse's "Damascus Steel" has several photos of folks still using tilt hammers in Germany (AKA swanz hammer)

[swedefiddle]

Good Morning Para Docks,

A Cam Hammer could also be called a Helve Hammer. A water wheel turned a shaft, which lifted an arm or beam with a top die on the end of it, then it fell onto the Anvil with the bottom die. Gravity and weight are the powers. If fingers got it the way, they were no longer connected to a Body.

When looking at Agricultural Equipment, look at the shaft that drives the Mower, the shaft that works the plunger on the Bailer, etc....... Don't look at the outside of the Machine, look at what it is actually doing. making something go up and down or side to side. The machine doesn't care which direction it was going. Which way would/could you turn it to go up/down. A Log Splitter doesn't always go side to side, hydraulics doesn't care where it is pointed!! Where is the Law that says a Power Hammer has to go up/down, most would function in another direction. Some people sit on Chairs to operate/use Power Hammers, three points of Balance, not two or one legged balance.

If you are wondering about thinking outside the Box. Who built the Box?? Some call it "Inventions".

Neil

[VaughnT]

There's a youtube vid where I guy built a DaVinci-style cam hammer.  Pretty simple mechanism but looked to be horribly inefficient.

[Branstetter]

I built one. And use it regularly. Although some thought it was a magnificent failure waiting to happen, it's still functioning just fine.  I had the video posted here at one time but can't seem to bring it up now.

 

Facebook link removed as you must sign up to view. Please post the video either on this site or on a site open to the public

 

[the other dave]

I worked for over ten years in a  chemical plant where we had six cam hammers on each of our two rotary kilns.  Each hammer had a 180 pound hammer weight and looked something like an inline treadle hammer with a stationary tube and a hammer which rose and fell through its center.  The biggest modification from the Da Vinci design was the placement of the cam in the middle of the head rather than between the pivot and the hammer head.  This allowed the block bearings for the cam shaft to be solidly mounted to the stationary tube and lubrication of the cam and the hammer head could be done with one grease fitting. 

And when we built a production unit  at a sister plant we used the same hammer design.  The biggest re-occurring problem was a tendency for the hammer head to get flung forward against the stationary tube.  Heavy wear in the front of the stationary holder was the net result but replaceable wear bars were another change.

[Frosty]

Do you have pics of the cam hammers?

Frosty The Lucky.

[the other dave]

Sorry Frosty but it's been 25 years since I worked there and the factory has been through several new owners.  And nobody I knew there is still left so getting pictures is out of the question.  On the other hand I can write a pretty good description of a cam hammer if that is acceptable. 

the Other Dave