Blacksmith hammers or trip hammers

If you’ve ever worked with a jackhammer, you’ll see the world of blacksmithing in a different light. Hydraulic hammers really fall into 3 basic categories, hydraulic presses, mechanical hammers, and pneumatic hammers. They are all designed to increase the amount of force you can apply to steel. This means that you can do more work in a given amount of time, and you can work with a larger bar. Suddenly this opens up a whole new creative reality with steel.

Hydraulic Presses

I don’t use one in my shop, but have used one years ago at another blacksmith shop. Hydraulics have tons of power (literally) and can force metal into many different shapes very effectively. They are useful for extreme controlled force applications, such as forcing steel into preformed dies, or cutting to specific lengths or angles, etc.

This is not an impact machine like jackhammers or jackhammers, and it is not fast. It can be used to mine steel, but this is tedious. Although it would save time drawing by hand and allow you to work with a larger bar, it would drive me crazy with the slow process.

Essentially the machine is a frame mounted hydraulic ram with an electric pump. You use a foot control to smash the metal. Step with your foot apply more force. Release your foot from the dies, then you can move the bar and apply force again in a different place.

There are a couple of positive aspects of a hydraulic press. They take up little space and do not require a special foundation. Prices are manageable for this type of tool. Around $2000.00 in my area. There is no impact noise or vibration with this type of machine. The hum of the hydraulic pump can be loud but it does not have the same nuisance factor for neighbors as the impact of a hammer. Presses are rated by the number of tons of pressure that the ram can produce. 20 tons, 40 tons, and 60 tons are common sizes.

mechanical hammers

All mechanical hammers work on a variation of the same principle. A rotating crankshaft lifts the counterweighted hammer head, then pushes it down for the next half of a revolution. The attachment on the other head of the hammer has to be a spring construction of some sort so that the shock is absorbed by the spring and not the crankshaft. The counterweight relieves some of the stress on the engine.

There have been many different configurations of jackhammers over the years. Little Giant comes to mind, but this is just one style. Others include Helve hammers etc. Mechanical hammers are classified based on hammer head rate. So a 25 lb Little Giant has a hammerhead weight of 25 lb. The greater the weight of the head, the more steel it can work under it, but the more motor it takes to make it work.

Something to think about. If your shop is outdoors but you don’t have electricity, you could run a jackhammer with a small gasoline engine. A bit pricey, but compared to the amount of work you could do this way, it might be worth it.

I’ve only done a bit of work with jackhammers, but a 1hp motor will do with a hammerhead weight of about 50lbs.

The beauty of a mechanical hammer is that it is relatively simple to build or repair. The concepts of the movement are very simple and easy to follow in slow motion. Power hammers were relatively common in industrial settings in the late 19th and early 20th centuries, so you may be able to find one at a good price in your area. The downside is that the parts can be impossible to find and you may have to craft your own.

You can also build your own mechanical hammer. It will take some tinkering, but a good working hammer can be done fairly cheaply. They don’t take up much space. Maybe 2 feet by 3 feet for a small one. They are a bit loud to run and have an impact sound. They need a good foundation, although a small one can get by on a small foundation. They are somewhat limited by the tasks you can do with them. If you’re creative with your tools, you can still get a lot of work done and save your arm.

Jackhammers

My personal favourite. The jackhammer was originally envisioned as a steam hammer for large industrial applications. Like mechanical hammers, they are rated by the mass of the hammer head and typically range from 50 lbs to 1,200 lbs or more. The higher end of the scale are massive machines that require gigantic foundations to function properly. This is poetry in motion to observe the use of a skilled blacksmith.

The principle behind the jackhammer is quite simple. Air pressure lifts a weighted hammer head, then something changes the air pressure and the hammer head falls under the force of the air pressure and then lifts again. The air in the bottom of the air cylinder acts as a shock absorber replacing the springs in a power hammer. This process creates a cyclic hammering of the steel. The weight of the hammer head and air pressure contribute to the force applied to the steel.

Most smaller blacksmith shops use sizes from 50 to 150 pounds. There are two subclasses of jackhammers that you need to be aware of. The autonomous version and the one with the air compressor. The autonomous uses two air cylinders. One is the compressor cylinder and it is driven by a motor. This cylinder supplies air to the hammer head cylinder. Therefore, each upward stroke of the driving cylinder pushes down on the hammer head cylinder and each downward stroke pushes up on the hammer head cylinder. The valve causes air to escape or be sent in varying amounts to the cylinder in the hammer head. This provides control of the stroke and the force applied to the steel. This cyclic timing is governed by the speed of the electric motor.

The air compressor connecting the jackhammer is powered by constant line pressure and has a feedback loop built into the design. The hammer’s head goes up and triggers a switch that tells it to come back down. Once you reach a certain travel point, another switch tells you to go back up. The amount of exhaust dictates both the speed and the force applied to the steel.

Although jackhammers seem to be a bit more complicated than a jackhammer, there are actually fewer moving parts and less to wear out. I find them most versatile. You can adjust your stroke and power simply by moderating your pedal. With a jackhammer, you have to make a mechanical adjustment to change the height of your blow. Its force is controlled by the speed of impact or the speed of rotation.