What hammer would you build ?

[VaughnT]

The japanese style of hammer is definitely appealing.  It has a strong industrial esthetic that's hard to beat, and the leaf spring definitely gives it a sense of power and majesty that you'll never get from a dorky coil spring.

From what I can tell, the entire frame could be built without a welder.  In photos, you can see the older ones put together with rivets, so I don't think it'd be too much of an issue to use good bolts and lock washers on a modern build.  Better to weld, obviously, but if someone lacks a welder, all they'd need is a good supply of drill bits and some patience.

I daresay that you could purchase the all the angle iron and flat stock needed for the same price you'd pay for just the 6x6 heavy-wall tube main column like used on most tire hammers.

What I'd like to know is how much adjustability there is in such a design.  How time-consuming is it to adjust the head so you can maximize the performance if you're driving a punch through a 2" hammer blank and then switch over to forging a few thin knife blades?

[arftist]

I would build a guided spring helve hammer if it were me.

The problem with the rusty design is that there is no intermediate flywheel. 

The slack belt clutch works directly between the motor and the pitman shaft. This leads to slow jerky starts and excess belt wear.

I solved this issue by installing an intermediate jackshaft with flywheels.

The motor spins the jackshaft with 2 tight vee belts. Then a flat belt pulley in the middlde of the jackshaft transfers the power through a wide flat power transmission belt. 

This belt is run slack and tensioned by a ball bearing equipped  idler pulley actuated via a foot petal. 

This has resulted in very powerful smooth blows and belts are still in service after 11 years.

The spare tire drive is nothing more than a clutch; a slack belt clutch is actaully far superior and much simpler.

In fact the tire drive is really no improvement since one is attempting to spin the entire hammer mechanism from the tourque of the motor alone. 

The weight of the tire agravates the strain it doesn't aid anything until high blows per minute when it does start acting as crude flywheel but rather unneeded at that point. 

In the long run a proper slack belt drive is far preferable.

Remember even a little giant has a flywheel BEFORE the clutch rather than after it.

It is every difference in the world.

I ran a dupont linkage hammer that was rigged up without the flywheel. It required a heavy foot on the petal then a herd blow or two before settling into a usable controllable speed.

That was the experience that made me design the flywheel drive. 

 

[JHCC]

 

1 hour ago, arftist said:

I would build a guided spring helve hammer if it were me.

The problem with the rusty design is that there is no intermediate flywheel. 

The slack belt clutch works directly between the motor and the pitman shaft. This leads to slow jerky starts and excess belt wear.

I solved this issue by installing an intermediate jackshaft with flywheels.

The motor spins the jackshaft with 2 tight vee belts. Then a flat belt pulley in the middlde of the jackshaft transfers the power through a wide flat power transmission belt. 

This belt is run slack and tensioned by a ball bearing equipped  idler pulley actuated via a foot petal. 

This has resulted in very powerful smooth blows and belts are still in service after 11 years.

arftist, do you have pictures/drawings of your hammer?

[VaughnT]

2 hours ago, arftist said:

I would build a guided spring helve hammer if it were me.

The problem with the rusty design is that there is no intermediate flywheel. 

The slack belt clutch works directly between the motor and the pitman shaft. This leads to slow jerky starts and excess belt wear.

I solved this issue by installing an intermediate jackshaft with flywheels.

The motor spins the jackshaft with 2 tight vee belts. Then a flat belt pulley in the middlde of the jackshaft transfers the power through a wide flat power transmission belt. 

This belt is run slack and tensioned by a ball bearing equipped  idler pulley actuated via a foot petal. 

This has resulted in very powerful smooth blows and belts are still in service after 11 years.

The spare tire drive is nothing more than a clutch; a slack belt clutch is actaully far superior and much simpler.

In fact the tire drive is really no improvement since one is attempting to spin the entire hammer mechanism from the tourque of the motor alone. 

The weight of the tire agravates the strain it doesn't aid anything until high blows per minute when it does start acting as crude flywheel but rather unneeded at that point. 

In the long run a proper slack belt drive is far preferable.

Remember even a little giant has a flywheel BEFORE the clutch rather than after it.

It is every difference in the world.

I ran a dupont linkage hammer that was rigged up without the flywheel. It required a heavy foot on the petal then a herd blow or two before settling into a usable controllable speed.

That was the experience that made me design the flywheel drive. 

 

I'm having a real hard time understanding what you're describing.  I agree that the spare tire design is less than optimal, but it seems to me that it's a compromise to allow for a very small footprint and easy parts to source.

Like JHCC, I'd love to see some photos or diagrams of your hammer design.

[Furnace1]

On 4/4/2016 at 5:02 PM, VaughnT said:

I'm having a real hard time understanding what you're describing.  I agree that the spare tire design is less than optimal, but it seems to me that it's a compromise to allow for a very small footprint and easy parts to source.

Like JHCC, I'd love to see some photos or diagrams of your hammer design.

I would like to see more of this also....I'm in the middle of a helve hammer build myself and have never been too enamored with the pulleys and belts flapping around on a rusty style hammer. That's why I have decided on the tire drive for mine where I can make a braking system as well, but this sounds interesting!...looking forward hopefully to pictures or diagrams.

[arftist]

On 4/4/2016 at 3:43 PM, JHCC said:

 

arftist, do you have pictures/drawings of your hammer?

 

[JHCC]

8 minutes ago, arftist said:

[picture]

Let me rephrase: do you have pictures or drawings that show the intermediate jackshafts and flywheels? And the slack belt clutch? Your system sounds very interesting, but more information (especially a video!) would be extremely helpful.

[arftist]

[arftist]

Ok the last 3pics are sideways.

This is the flywheel. It is an old 16" lathe faceplate.

On the opposite end is a 16" double vee groove pulley. The motor (2hp Baldor 1750 rpm)

drives the flywheel assembly via 2 vee belts (Gates power rated.)

Betweeen the face plate and the vee belt pulley is a cast iron flatbelt pulley.

The jackshaft runs on pillowblock  bearings one of which is visible.

When the motor is switched on this entire assembly spins.

The idler is the aluminum pulley. This is connected  to the foot petal.

The idler pulley is fitted with sealed ball bearings. 

Above the idler is the pitman crank.

The pitman is a slice of 14" pipe wich I crowned. 

The belt is 4 ply power transmission belt. 

The belts are all original. 

I showed the top of the machine to aid the  visualuzation process.

All of this running gear is behind the hammer and below the anvil.

The base plateis 28x40"x 1.5"thick. 

The base plate could easily be smaller but  I wouldn't go thinner purposely.

This machine is markedly NOT top heavy. 

This hammer strikes at 220 b.p.m.

The ratio is easy to acheive due to the two seperate beltdrives so there is no need to compromise and use a supper small motor pulley for the sake of achieving a significant speed reduction.

[basher]

On 31 March 2016 at 7:12 PM, stuarthesmith said:

the best design I have ever seen for a tire hammer is on youtube.  Google "Japanese Tire Hammer Youtube" and check out the video.  Leaf springs hit way harder than coil spring actuated heads.https://www.youtube.com/watch?v=Sq4NZin-MBY

I would be interested in how you quantify this? do you mean per Hp or per lb of ram or some other measure? 

Would the hammer power not depend more upon the speed of revolution and head travel (and therefore ultimately HP) I am sure that the non hitting weight moved may come into it as well (as a loss).

 I have both types of spring hammer and both are pretty snappy, unfortunately they are not the same weight of head so hard to compare.

My assumption (possibly wrong) is that the leaf spring hammer were in general an older design then the coil spring hammers, I wonder what their advantages were?

Arftist, I would have agreed with you on the fly wheel before clutch being of prime importance, however i have used a few very good hammers that  omit this and still run very well. so it is not essential .

 the czech prako guided helve hammers hammers have a small fibre drive wheel  acting as a clutch direct onto a metal flywheel and they are excellent hammers.

[arftist]

Basher; just taking a wild guess but the leafspring may be capable of more or longer whip.

The Dupont mechanism may be more prone to harmonic imbalance at a lower frequencey. 

When I really want to move metal I use at least an inch of clear space between the dies. Otherwise the whip is restrained.  

[JHCC]

Thanks for the photos, arftist. Much to think about.

Could you give us a shot of the whole machine? Thanks!

[arftist]

 

 

1 minute ago, JHCC said:

Thanks for the photos, arftist. Much to think about.

Could you give us a shot of the whole machine? Thanks!

Yeah not for a while. 

I am opening a new shop shortly. In the mean time I showed what I could get to.

Do you understand the drive system clearly?

[JHCC]

Just now, arftist said:

 

 

Yeah not for a while. 

I am opening a new shop shortly. In the mean time I showed what I could get to.

Do you understand the drive system clearly?

Yes, that makes much more sense now. Thanks. Let me know when the new shop is finished; I travel all over New England for business and would love to see it in person.

[arftist]

2 minutes ago, JHCC said:

Yes, that makes much more sense now. Thanks. Let me know when the new shop is finished; I travel all over New England for business and would love to see it in person.

That would be great. 

Sometime in June hopefully.

[arftist]

38 minutes ago, basher said:

Arftist, I would have agreed with you on the fly wheel before clutch being of prime importance, however i have used a few very good hammers that  omit this and still run very well. so it is not essential.

Correct, it is not essential.

It is however preferable and I daresay the hammers not so equipped would be improved for it. 

Smoother starts, better control and faster acceleration would clearly result due to the energy stored in the flywheel assembly. 

This is especially true in the case of tire cluthes where the mass of the tire resists movement in addition to the weight of the tup and associated moving parts.

[Judson Yaggy]

Best use of a lathe faceplate in a blacksmith shop goes to...

[basher]

So basicaly the statement that leaf spring hammers are more powerfull than coil spring hammers is anecdotal?

 

[VaughnT]

On April 7, 2016 at 5:22 PM, arftist said:

Ok....

Thanks, Arf.  The photos clear up the confusion. You don't appear to have any kind of braking system on the pitman crank, correct?  Also, I noticed your use of the turnbuckle and was curious to know how much practical adjustment this allows for.  I was thinking about going the same route, but wasn't sure if it was worth it if it means having to build a second larger hammer if I want to get into larger work.  The Preston tire hammer caught my eye because it can be adjusted very quickly.

 

Coil springs are very common and can be found in a lot of machines, but most leaf springs have to be custom made because the ones you find on cars are stacked upside down and are too long between the eyes.  From a corporation's standpoint, it would have been a lot cheaper to buy a standard COTS coil spring from the spring maker or wholesaler rather than have custom leaf springs engineered and made just for your hammer style.    Even today, the average joe-in-the-garage can look up coil springs on the internet and find one from any of a dozen sources that will work well for his home-built hammer.  Leaf springs, as beautiful as they are, would have to be custom made.

[arftist]

41 minutes ago, VaughnT said:

Thanks, Arf.  The photos clear up the confusion. You don't appear to have any kind of braking system on the pitman crank, correct?  Also, I noticed your use of the turnbuckle and was curious to know how much practical adjustment this allows for.  I was thinking about going the same route, but wasn't sure if it was worth it if it means having to build a second larger hammer if I want to get into larger work.  The Preston tire hammer caught my eye because it can be adjusted very quickly.

 

Coil springs are very common and can be found in a lot of machines, but most leaf springs have to be custom made because the ones you find on cars are stacked upside down and are too long between the eyes.  From a corporation's standpoint, it would have been a lot cheaper to buy a standard COTS coil spring from the spring maker or wholesaler rather than have custom leaf springs engineered and made just for your hammer style.    Even today, the average joe-in-the-garage can look up coil springs on the internet and find one from any of a dozen sources that will work well for his home-built hammer.  Leaf springs, as beautiful as they are, would have to be custom made.

My spring pack cost $60.

The leaves were cut  and straightened while I waited.

Most of the hammer was custom made. 

The turnbuckle gives plenty of adjustment but I wouldn't use one again. 

A round rod running in a tube. 

A split clamp on the end of the tube tightened with one  bolt. Much faster than a turnbuckle.

Really not sure what your point is about the coil springs. These are one off hammers mostly made by their owners. 

When engineering for ones own use one can place more enthesis on performance/longevity and less upon widget cost. 

[VaughnT]

1 hour ago, arftist said:

Really not sure what your point is about the coil springs.

I was addressing the later comments about leaf v. coil in hammer build design.  Home-built or factory-made, coil springs are easier and cheaper to source because they're so common.

 

What's the max working size on your hammer?   I'm trying to imagine how the split clamp would work under the impact issue.  It seems to me that the threads on the turnbuckle keep the rod from collapsing after repeated shocks, but using a split clamp would allow for slippage since it's just friction holding things together.  I like the idea since it's a lot easier to adjust, but...

[Judson Yaggy]

33 minutes ago, VaughnT said:

coil springs are easier and cheaper to source because they're so common.

Incorrect.

A piece of flat bar is a leaf spring.  Stack 'em up, curve them a little, tweak the ends a little, still a piece of flat bar. Any truck spring shop can make you a stack of leaf springs to order while you wait.

 Coil springs, especially in the somewhat unusual configurations that work well in Dupont linkages are specific rod diameter, coil diameters, lengths, and work better with flattened ends.  They CAN be purchased but come in somewhat limited  sizes and unless you live near a very custom spring shop will have to be ordered in from several states away.  And that is just stock coil spring sizes, try ordering a custom size from a spring shop.  Some can do it but not all and it'll cost more.

I've rebuilt several antique mechanicals with Dupont linkages (not just LG's, THOSE you can just order) and helped a few buddies build Rusty type hammers and having actually laid out cash for power hammer springs I can say that sourcing a leaf spring was far easier than a comparable coil spring.  

[VaughnT]

1 hour ago, Judson Yaggy said:

Incorrect.

A piece of flat bar is a leaf spring.  Stack 'em up, curve them a little, tweak the ends a little, still a piece of flat bar. Any truck spring shop can make you a stack of leaf springs to order while you wait.

 Coil springs, especially in the somewhat unusual configurations that work well in Dupont linkages are specific rod diameter, coil diameters, lengths, and work better with flattened ends.  They CAN be purchased but come in somewhat limited  sizes and unless you live near a very custom spring shop will have to be ordered in from several states away.  And that is just stock coil spring sizes, try ordering a custom size from a spring shop.  Some can do it but not all and it'll cost more.

I've rebuilt several antique mechanicals with Dupont linkages (not just LG's, THOSE you can just order) and helped a few buddies build Rusty type hammers and having actually laid out cash for power hammer springs I can say that sourcing a leaf spring was far easier than a comparable coil spring.  

Incorrect.  Or correct, depending on how you look at it.

While a flat bar can definitely do as a leaf spring, the spring packs used on a lot of the old hammers, in place of the Dupont Linkage, were a very specific size, shape, weight, etc.  If you look around other old machinery, you can see that these leaf springs were not a common size or shape like you might see on all sorts of different types of equipment around factories and farms.

Today, you can run down to the corner store and buy a leaf spring pack, but it will be something mass-produced for trailers or golf carts.  If you want something designed just for you, you have to find a spring shop.... and you might not have one nearby.

The point that I was trying to make is that coil springs replaced the leaf pack in the LG-style hammers because it made sense for a company to source their parts via the cheapest route possible.  A COTS coil spring for the LG-style hammer could be the same coil spring being used for any of a dozen other applications we don't know anything about.  Way back in the day, the folks at Little Giant looked around (I'm just making this part up) and found that they could get the right performance from X coil spring for half the cost of what it took to get a leaf spring custom made for their hammers.  So, they went that route.

I'm not saying that's what happened, exactly, but it's certainly a very reasonable train of thought when you consider how common the coil spring is.

I pulled this image off the net since it demonstrates what I was trying to say.

The leaves are stacked upside-down compared to how we normally see them, and the size is different from any other springs I've ever seen on balers, rakers, bunchers, etc.  While there might have been some other industrial uses for this spring pack, I'm betting that they were custom made for this hammer builder.  Maybe not.  I'm just following a train of thought based on my experience.

 

My apologies for derailing the thread.  I'll comment no more on springs.

 

[arftist]

14 hours ago, VaughnT said:

I was addressing the later comments about leaf v. coil in hammer build design.  Home-built or factory-made, coil springs are easier and cheaper to source because they're so common.

 

What's the max working size on your hammer?   I'm trying to imagine how the split clamp would work under the impact issue.  It seems to me that the threads on the turnbuckle keep the rod from collapsing after repeated shocks, but using a split clamp would allow for slippage since it's just friction holding things together.  I like the idea since it's a lot easier to adjust, but...

Talk to Jerry Allen at Wizzard forge. 

He designed the modern incarnation of the spring helve hammer known as the "Rusty " or more correctly the Apalachian Hammer. 

He designed the clamp style I described as far as I know or at least passed it on to me. I would recomend stout stock and a thick grade 8 bolt.

The max working size of my hammer is very large. There are two 1.5" spacers under my bottom die which can be removed and interchangeable spacers under the pillow block bearings that the springs pivot on. The turnbuckle alone provides 8" of lift before the spring geometry goes south. 

Then if I still don't have enough room I can unbolt the tup guide and raise it 3 or 6  ". 

[arftist]

12 hours ago, VaughnT said:

Incorrect.  Or correct, depending on how you look at it.

While a flat bar can definitely do as a leaf spring, the spring packs used on a lot of the old hammers, in place of the Dupont Linkage, were a very specific size, shape, weight, etc.  If you look around other old machinery, you can see that these leaf springs were not a common size or shape like you might see on all sorts of different types of equipment around factories and farms.

Today, you can run down to the corner store and buy a leaf spring pack, but it will be something mass-produced for trailers or golf carts.  If you want something designed just for you, you have to find a spring shop.... and you might not have one nearby.

The point that I was trying to make is that coil springs replaced the leaf pack in the LG-style hammers because it made sense for a company to source their parts via the cheapest route possible.  A COTS coil spring for the LG-style hammer could be the same coil spring being used for any of a dozen other applications we don't know anything about.  Way back in the day, the folks at Little Giant looked around (I'm just making this part up) and found that they could get the right performance from X coil spring for half the cost of what it took to get a leaf spring custom made for their hammers.  So, they went that route.

I'm not saying that's what happened, exactly, but it's certainly a very reasonable train of thought when you consider how common the coil spring is.

I pulled this image off the net since it demonstrates what I was trying to say.

The leaves are stacked upside-down compared to how we normally see them, and the size is different from any other springs I've ever seen on balers, rakers, bunchers, etc.  While there might have been some other industrial uses for this spring pack, I'm betting that they were custom made for this hammer builder.  Maybe not.  I'm just following a train of thought based on my experience.

 

My apologies for derailing the thread.  I'll comment no more on springs.

 

First of all the stack in the photo is merely mounted upside and even then only in your opinion. Every seen a Corvette rear end or for that matter a buggy seat?

Second they always were and still are custommade. Especially back then.

In the era you are discussing outsourcing was unkown other than keeping the forge at any given factory somewhat away from the production line. (Smelly blacksmith stir their coffee with their thumbs).

Back then even the bolts were made in house (If it is profitable to that fellow to make our bolts then we shall make them ourselves and keep more profit in house).

For that matter the taps and dies as well. Many manufacturers even used proprietary threads. I have buckets of huge oddball taps I collected as the old 

industrial revolution era mills shut down in New England.

You are trying to apply very modern (and not clearly better) business practice to an earlier time.

On about coil springs in hammers (and I am no expert but I do know this)

The dupont mechanism and Dupont hammers are a good thing. The Little Giant is a cheap hammer desingned for mass production. That doesn't mean it is the best design, just the one one very abitious man chose to copy.

Many far superior hammers DO NOT use the dupont mechanism.