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Mechanics Corner: Hammers: Not created equal

Andy Overbay for Progressive Dairyman Published on 24 August 2017

You know the old saying, “If your only tool is a hammer, the whole world looks like a nail.” While that might be the case, the next question has to be, “What kind of hammer do you have?”

Hammers come in all kinds of shapes and sizes for one overarching reason: They have very different jobs and are rarely interchangeable.



If you ask the average person on the street to pick out or draw a hammer, I think most folks would come up with a claw hammer – and for good reason. A claw hammer is pretty much the hammer of the household. For driving nails and prying things apart around the house, a claw hammer works just fine as long as the handle holds out. However, even claw hammers have many variations in form and weight.

Having a light hammer around the house or shop can be a handy thing. There are times, though, even in household applications, where a heavier hammer is needed. People unfamiliar with tools and their regular use generally shy away from heavier versions; however, hammers too light for the job will most likely cause more damage than good.

Around the farm shop, whether you’re rebuilding a transmission, doing chassis or brake work, making leaf spring repairs, working out suspension fixes, tackling some engine-related repairs or seating seals and bearings, a hammer is a handy tool. Once again, though, different jobs call for different hammers.

Those of us who do our own tire repair know very well a light claw hammer has no place around putting a tire on a rim, or using a tire tool to stretch a tire off the rim, for that matter.

In my own shop, I probably use my 24-ounce ball-peen the most, followed closely by my 4-pound shop hammer (a mini sledgehammer). Even among similar types of hammers, differences exist. For instance, you will find ball-peen hammers weighing from 2 to 48 ounces.


For automotive work, the most common weight range will be 8 to 16 ounces. Special hammers with plastic, brass, wooden or rawhide heads (or tips) also come in handy for jobs where you need to be careful with the material or item you are working on. Another tool that finds a lot of use around the shop is the rubber mallet.

In fact, if you are in the habit of making your spouse angry, keeping the rubber mallet in a conspicuous place for the offended mate to find and throw is highly advisable … not that I know anything about that in the last 32 years.

Many hammers used in the farm shop can fall into the “machinist’s hammer” classification. The most common of these is the ball-peen hammer. There are also cross-peen hammers and straight-peen hammers. The peen is the shaped end of the hammer’s head.

On the other end you have the post (cylindrical tip) and the face (flat circular end). The peen can be used to shape metal. The word “peen” actually means “shaped for denting or chipping.” The ball-peen can be used to hammer a bolt head or nut until the metal swells and actually prevents it from jarring loose.

Straight-peen and cross-peen hammers can swage (cold shape) metal. Welders often chip excess weld slag with them. I personally use a welding hammer with a tapered tip to clip slag.

My experience with a welding hammer reminds me to stop right here and share an important point. No matter what job you have or which hammer you choose, safety glasses are a good idea. I was doing some light welding in the shop one day and needed to knock the slag off my work. I flipped my helmet up, grabbed my welding hammer and gave the hot weld a quick whack.


The slag came free – and a small piece hit me right in my right eye tear duct. I don’t recall what I was welding on, but I don’t think I will ever forget the sound of that slag hitting my eye. Think of a raw steak hitting a hot grill and you are pretty doggone close. Luckily, other than a painful burn, I had no permanent damage to my eye. I do keep the safety glasses handy now though.

Using the appropriate hammer properly is important as well. When striking material or parts with a hammer, you should try to hit the part squarely. The face of the hammer should be as parallel as possible to the surface you’re hitting it with. This protects the hammer and keeps you from chipping or deforming what you’re striking.

Strong, heavy hammer blows are rarely needed and may be a sign the hammer is too light or incorrect for the job. Using a hammer that way can damage the tool or destroy the part you’re trying to remove or install. Instead of banging the hammer down on a part, learn to hammer with a bouncy, rhythmic sound.

When hammering to properly seat a seal, a bearing race or a slip-in bearing, you have to tap all around the part to get it to seat evenly. Tapping on just one side won’t work well. Bearing driver kits with a knurled handle that screws into flat discs of different sizes can help seat parts evenly.

If the part is seating over another part, it may be impractical to use such disc-type drivers, but a socket or piece of pipe of the right size and shape will do the job. Tap lightly all around and be patient.

Sometimes mechanics will use two fair-sized hammers with almost the same-size heads to break a heavily rusted part loose. They use one hammer to tap the other into the part, again and again, with a repeated, regular rhythm. Almost without fail, after a few minutes the corroded part will break loose.

A nice thing to have around your shop is an assortment of different-sized wooden dowels and wooden blocks that can be used together with a hammer to do various jobs.

After a favorite tractor’s narrow front end lost a battle to a huge groundhog hole, we had to gently reshape the bottom of an old oil pan back to its original shape by hammering on a soft wooden block held against the bottom of the pan that we moved just a little between moderate blows. Attempting to do this with only the face of the hammer would have just caused dents or, worse yet, hammered right through the pan.

Once again, selecting the correct hammer is very similar to selecting a wrench of the correct size and configuration. You will have a great deal more success with a great deal less stress … which farming has plenty of anyway.  end mark

Andy Overbay holds a Ph.D. in ag education and has more than 40 years of hands-on dairy and farming experience.

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