Dressing Tools, Part 1

by Albin Drzewianowski

Continuing on the same topic as the last two installments of this column, we are going to talk about the next step, which is dressing your tools. Odds are, that old used hammer head that you got at the flea market for 50 cents probably has some dings or chips in the face and/or the pein.

Also, even if you buy a brand new hammer from the hardware store, the face will still need to be dressed. Most new hammers have a very pronounced bevel ground around the outside edge of the hammer face. This is done by a machine. If you forge with this kind of hammer, (or an old used hammer that has dings or chips in the face or edges) you will see that those defects can leave marks in your steel. Don't forget to check the pein. Most new hammers come with a cross pein that is straight across and has very sharp edges and corners. Those edges and corners need to be rounded over so that they do not leave marks in your work. Also, the overall pein, whether a cross pein or straight pein should have a slight curve to it. Some blacksmiths prefer a much more pronounce curve other a less pronounced one.

Other tools also need to be dressed periodically. Any tool that is struck with a hammer will eventually start to get some "mushrooming" on the end where it is hit with the hammer. That edge of metal which is spreading out needs to be ground off. The working ends of chisels and fullers also periodically need to be re-ground.

This process of dressing tools is not just for when you get them. It is a continuing process. Since we are constantly hitting steel with steel, edges get dinged up or deformed and need to be cleaned up. Make it part of your regular maintenance schedule.

There are a number of tools and materials available to use when it is time to dress your tools. Since for the most part we are talking about tools made from a tool or spring steel, we will be using power tools. If the tool is made from mild steel, you can use a file. Back to the power tools: the tools of choice are a angle grinder, bench grinder and belt sander. This month we will talk about working with the angle grinder. We will cover the bench grinder and belt sander next time.

For the beginner, I think that the hand held angle grinder is probably your best bet as a starting point. Get a 4 1/2 inch angel grinder in the $60-$80 range. The ones you see in the $20-$40 range don't have enough power and often don't last very long. A 7 inch angle grinder is over-kill, a lot more power than you need at this point and an awful lot heavier. Once you have the angle grinder, you will need a cup brush, a grind stone and a number of flap discs in different grits.

The cup brush is a circular wire brush with the wires perpendicular to the handle. The best ones to get are the knotted stainless steel cup brushes, They are the most aggressive and last longer, even though they are more expensive. The cup brushes are great for removing rust, dirt and paint. They are also very handy for removing slag when welding. If you have fire scale on your iron work after forging, once the metal is cool, only a powered wire brush will remove it; which is why you want to use a hand wire brush really well while the metal is hot to get off as much scale as possible.

Next you want one or two grind stone discs to fit on the angle grinder. If you only use one, get a medium, about an 80 grit. A better system would be to have a course, 40 grit, and a fine, 120 grit. If there is a lot of metal that needs to be removed, you start with a grind stone. This will remove a lot of steel, but will leave serrations/scratches on the metal from the stone.

The next step is to go to the flap discs which are designed for one-step grinding, blending, and finishing of metal. These are discs with overlapping layers of sandpaper. They come in many different grits. They can be aluminum oxide for general purpose or zirconia which has a more aggressive cut and longer life. After using the stone you start with a coarse grit flap disc and then move up to the finer grits. This takes out the scratches from the stone and leaves a nice polished surface. If you only have a little bit of metal to remove, you can start with the flap discs.

Safety: Always Wear Eye Protection!! These tools are revolving at about 10000 rpms and pieces of the disc or the metal you are grinding can come flying off at incredible high speeds. Also, ALWAYS leave the guards on the angle grinders. It may seem to be more convenient to take them off, but they are there for your protection. The section you have been grinding on can become very hot, don't burn yourself.

Technique: Clamp the hammer head or chisel in your vise at a convenient angle. Use a very light touch with the angle grinder. These tools work by grinding away the metal, so the tools will get hot very quickly and can get hot enough to damage the temper in the tool. Always have a container of water handy so that you cool the section you have been working on. When I am doing this kind of work, I make it a point to never let the metal get so hot that I can not comfortably touch it. Adjust the angle of the tool in the vise, rather than to try and hold the angle grinder at uncomfortable angles.

As with all aspects of blacksmithing, this takes practice. Work with a light touch. Grind a little bit and take a look, then grind some more. Work from both sides and try to keep the tool symmetrical at all times. Except for the actually cutting edges which need to be sharp, most edges on hammers and tools should be rounded over.

Another handy use for angle grinders is as a cutting tool. You can get very thin cut-off disks that will fit the angle grinder, and use them as a hand held chop saw. You need to be very careful to hold the tool very steady and straight in the cut otherwise the disc will bind and break. I have seen both factory made and home made stands in which you can mount your angle grinder to give you the equivalent of a small chop saw.

I find these tools so handy that I have 3 angle grinders: one has a wire brush, one a stone, and the last one is used with flap discs. When I had only one, I found that I was constantly changing from one media to another. With dedicated tools, I can grab the one I need and not be constantly changing.

There are a lot of other accessories and media that you can buy and use with your angle grinder. But those described in this article will get you off to a good start. A common question for beginners is, where can I get these kinds of tools and supplies??? The angle grinders themselves are available from many sources, including Sears, farm stores, Lowes/Depot etc. It is the consumables, the discs and wire brushes that are harder to come by. Especially if you want a size or grit other than the most common. For those, you can go to welding supply stores or get them through catalogs/web sites. MSC and McMaster? Carr have an immense variety of grind stones, discs, sanding belts, etc to choose from.

MSC: 800-645-7270 website: http://www.mscdirect.com/ If you call them they will send you a 4500 page catalog, free. Once you start buying from them, you will get monthly sales catalogs.

McMaster Carr: 630-833-0300 web site: http://www.mcmaster.com/ It is very difficult to get a hard copy of their catalog. You have to be a major company to get one. But you can go to their web site, get the part numbers and then call them on the phone to place your order or you can order through the web site.

Next issue we will talk about bench grinders and belt sanders and how to use them.

-- RebStaup - 25 Jan 2008