Nick

DePew-type hammer with flywheel and ratchet treadle?

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I've been thinking about building a power hammer, something small along these lines:

 

helve5-1.jpg

 

Today I found a video of an old Barnes treadle-powered table saw, which works with a large flywheel and a ratchet, operated by a chain attached to the treadle.  Like an old pan forge, it lets the axle rotate freely from the treadle (or tiller), so pushing down keeps the speed on the flywheel without having to keep pumping on it constantly.  The chain can be seen in action in this video:

 

http://blip.tv/popular-woodworking-videos/barnes-table-saw-4772756

 

That got me to thinking, could this drive system be adapted to the little hammer above?  I imagine it would need some kind of brake on the flywheel to keep the hammer from pounding merrily along after the iron's back in the forge.  I'm not opposed to an electric motor, I just thought this was an interesting setup.

 

Any thoughts on the workability of the design?

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The design looks well thought out, however, I think it's a sheet metal hammer.  There doesn't appear to be a "soft link" in the drive.  All powerhammers have some sort of spring or soft linkage  to cushion the hammer in case the stock between the dies changes thickness.  Without the spring link, the hammer is rigid back to the motor and something will break if the dies can't make a full cycle.

 

Look at tire hammer designs and have a look at this one, which is a tire drive "rusty" hammer http://www.bladesmithsforum.com/index.php?showtopic=28582&hl=

 

Geoff

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The soft link is the leaf spring right on top. You can see that the spring is connected to the helve near the center. And the drive rod connected to the leaf spring is on the end. The spring can flex freely. Not the best connection out there but I sm sure it works fine enough. In fact you can see a pile of scale on the floor under the anvil

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Greetings Nick,

 

Looks like a snappy lil hammer...  Short stroke,,,  No head weight ,,,  aprox.  6;1 ratio on speed..  guessing about 325 rpm..  The only provision for adjustment for thickness is the connector shaft in the rear...   I don't think this lil fella would do much work on large stock...   With a little more effort you could make the tried and proven Clay Spencer tire hammer..   Just an old boys 2c

 

Forge on and make beautiful things

Jim

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Yes, I would want to make some changes to make it adjustable, and perhaps a little bigger, along the lines of a Hawkeye helve hammer.  But I rarely ever work with big stock, most of what I do is quite small, so I don't need a giant of a machine.

 

I did some looking through the Google patent collection, and it seems I'm not the first one to have this idea.  There are a few from the turn of the century that are similar, one can even be foot, hand, or belt driven.  Another has a clutch lever that will disengage the helve when not in use, though instead of a pitman arm it lifts the hammer with a cam wheel on the back of the helve.  The downside is that in all of them, the treadle is directly linked to the drive shaft, so it will always be in motion, as opposed to the Barnes saw, which engages the drive with a pawl. 

 

I won't be building anything yet, just getting ideas right now, really.

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The above picture of the helve hammer sure looks like it was made from the plans by Jr. Strasil http://www.iforgeiron.com/page/index.html/_/blueprints/100-series/bp0159-helve-hammer-r390

I have personally used the helve hammer made by Jr. Strasil in the link I posted above - that little hammer packs a punch, and will move metal!!!!

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If you are building a unguided small helve hammer I would use a 20lb sledge hammer head. Mount it on a nice long 3 foot handle. I would use a u shaped leaf spring like the "Hathorns power hammer". If you have a good long range of swing say 10" at the head, it would hit very hard

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Jeremy, I was thinking the same thing. As soon as I saw the picture I said, "JUNIOR!!" :D

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I have one of those depue hammers 16# head at 525 bpm  dose move some metal. Made  to sharpen plow shares and they are good at it.   If you want to draw steel pound for pound they are hard to beat.

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The above picture of the helve hammer sure looks like it was made from the plans by Jr. Strasil http://www.iforgeiron.com/page/index.html/_/blueprints/100-series/bp0159-helve-hammer-r390

I have personally used the helve hammer made by Jr. Strasil in the link I posted above - that little hammer packs a punch, and will move metal!!!!

 

Good to know it's a good hammer.  This is the one that made me think of putting a power hammer in my shop.

 

If you are building a unguided small helve hammer I would use a 20lb sledge hammer head. Mount it on a nice long 3 foot handle. I would use a u shaped leaf spring like the "Hathorns power hammer". If you have a good long range of swing say 10" at the head, it would hit very hard

 

3' sounds about right for the size I'm after.  I've thought about mounting the linkage forward of the pivot like the Hawthorn and Hawkeye hammers, though I've seen some others with it at the rear that seem like they'll work (like above).  Lots of ideas!  I've sketched out a design closer to Jr. Strasil's, though I will keep looking at other designs.  I'll post a picture of what I'm thinking of later. 

 

What I really need is my own welder so I can work on these things in my own garage.  One thing at a time...

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Nick - I'm so glad you posted about this. I was looking at the exact same design a few weeks back. I fancy building one and leaving at my folks place. 

 

Please be sure to update us with your build if you go ahead with it...

 

Andy

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For these hammer to be effective they need to run fast 400 plus bpm   it will need a lot more than a sledge hammer handle. my DePue  helve is 4 inches wide.  be safe guys

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Yes I would be more inclined to use a iron rod in place of a wood beam for the hammer head. If you used a large cross peen for the head maybe you could set it up to quickly rotate so you could use the peen or flat face!

Best of luck to you

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One of the biggest problems with the Little Giant Easy was the steel helve.   They all broke. If there  was something better than hard maple for a helve Bradley would have used it.  We all learn from others mistakes and success.

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My plan was to hew and season a maple helve myself.  Finding the wood won't be a problem, I live in the middle of a forest.  If I do manage to adapt it to foot power it probably won't have as high bpm, but if it does turn out to be a failure in that way I can convert to an electric motor.

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Greetings Nick,

 

You are going to need a big breakfast and a large flywheel for a foot powered unit..   I would like to see your plans..  By the way I have some big flywheels left over from my line shaft building.  Energy in ... Energy out less friction and heat loss..

 

Forge on and make beautiful things

Jim

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It's all still pretty theoretical at this point.  My shop right now isn't a good place for the hammer (soft sandy floor and the electrical won't handle the load if I do put a motor on), so the hammer will be built after I move to a new shop.  I will make a cleaner copy of my sketch and post it. 

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Greetings again Nick,

 

You may consider designing your hammer to use an electric motor..  Until you get it in your new shop you could use a small gas engine.. I have done this in the past with a table saw and it worked well..   I like the fact that your always thinking and planning.   Any way this old boy can help just ask..

 

 

Forge on and make beautiful things

Jim

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If you're using a relatively light sledge as the helve and head of the hammer, how much motor would you realistically need?

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Greetings again Nick,

 

You may consider designing your hammer to use an electric motor..  Until you get it in your new shop you could use a small gas engine.. I have done this in the past with a table saw and it worked well..   I like the fact that your always thinking and planning.   Any way this old boy can help just ask..

 

 

Forge on and make beautiful things

Jim

 Thanks, Jim :)

 

Here is a sketch of what I'm thinking.  It's only a sketch, not to scale, no measurements or details, but should give an idea.

 

Here's the right side elevation of the hammer.  For this arrangement I've based it pretty much off Jr. Strasil's.  The basic arrangement of the frame, linkage, and hammer are the same.  The large flywheel is located about center of the frame, supported by the horizontal brace. 

 

post-417-0-49898500-1391473999_thumb.jpg

 

Here's left side elevation showing the drive only.  The drive axle has a sprocket which has a roller chain attached to the treadle on one end, and a swing arm on the other.  The treadle and swing arm are returned by coil springs.  The sprocket has two pawls which engage a ratcheted wheel on the drive axle.  Pushing the treadle down pulls on the chain, making the swing arm pivot, driving the flywheel.

 

post-417-0-41711100-1391474184_thumb.jpg

post-417-0-74357900-1391474171_thumb.jpg

 

There's an idler pulley clutch, same as the original hammer, it is engaged by a lever pivoted on the anvil post.  The lever can engage a notch to keep the idler against the belt.  A good push on the treadle to get the flywheel spinning, pull the lever, hammer works.  Release the lever, the flywheel may still be spinning but the hammer won't beat.  I figured this hammer's size and design would be a good choice for a drive like this since it is smaller. 

 

So those are my initial thoughts.  I've looked at putting the pitman in the center, too, but haven't worked it out yet. 

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If you're using a relatively light sledge as the helve and head of the hammer, how much motor would you realistically need?

!/2 hp

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