Priscilla & Luke Smith @PLSmithed
Intro to Metalwork
This video was made in partnership with BESSEY Tools North America.
In this two part series, you are going to get a general overview of what you can do with metal, learn a few basic skills, and get a list of the tools we recommend you’ll need to get started with metal fabrication. In the first video we’ll show you what you can do with different tools and materials, and cover all the prep and safety measures. In the second video we’ll take you through each step in welding together a base for a side table as just one way to start incorporating metal into your woodworking projects. You’ll want to watch both videos to get the most information, and to make sure you walk away feeling confident to get working on your next metal project!
What You Can Do With Metal
Metalworking is an umbrella term, and is fairly generic when it comes to describing what is actually happening, as there are a wide range of disciplines and materials used in the realm of metalwork that are specific to a certain procedure or end result.
For example, Fabrication is an additive process used for creating metal structures by cutting, bending, and assembling components. Conversely, you have a subtractive metalworking process such as Machining where parts are made using controlled removal of material. Then there is Forging, where pieces are shaped using localized, strategic compressive forces.
There are many specialties within the metalworking world, and some often overlap, but ultimately, it’s broken down into three main categories: Forming, Cutting, and Joining.
A Little Metallurgy Lesson
Steel or Iron? What’s the difference? This isn’t a chemistry lesson so we’ll keep this brief, but did you know that 94 of the 118 elements on the periodic table are classified as metals? Me neither without looking that up! But when it comes to metalworking, there is a lot of chemistry involved.
Metal is divided into 3 categories:
- Ferrous (containing iron)
- Nonferrous (contains no iron)
- Alloys (contains a combination of other metals and elements).
Ferrous metals have a greater strength and durability, with iron in their compositions. Non-ferrous metals are non-iron-based materials found on the earth as chemical compounds such as copper, aluminum, gold, etc. Any metal category combined with other categories is considered an Alloy. Each metal category is further categorized into grades depending on the unique structure, properties, and usage of each metal.
The most commonly used metal on earth is the alloy steel, and yes it’s an alloy because through the manufacturing process, the naturally occurring Iron element is combined with percentages of carbon to produce the steel. The amount of carbon and/or other elements added to the Iron will result in the different grades of steel that have been set by governing bodies. Different countries have their own systems, sometimes multiple, but all essentially grade a metal with some combination of letters and/or numbers. For the sake of this class, we are going to focus on using Mild Steel, which is a low carbon content steel. This is the type of steel you can pick up at any local hardware store such as Home Depot or Lowe’s. If you’re lucky enough to be near a metal supplier, that is the ideal option for sourcing a wider variety of material at a better price than a hardware store. Alternatively, an extremely convenient way to get a wide variety of metals shipped directly to your door is through Online Metals. They are our go-to place for sourcing materials.
Safety First!
Having the proper protection when working in a shop is always one of the most important things, and working with metal makes no difference. You always want to make sure you have the proper eye protection, ear protection, a good pair of gloves, a respirator, a fire extinguisher, and when welding, a quality welding helmet/goggles and a welding jacket.
Cleaning the Metal
Most of the time that you bring home your steel for your project, you’ll find it has a dull, dark gray finish on it. That is called mill scale and it’s a thin layer of oxidation left on the steel after it is produced during the hot-rolling process. When it comes to welding, it’s best practice to remove it from the area that will be welded. The mill scale is made up of the impurities in the steel as well as any other junk and oils that came into contact with the steel during and after the manufacturing process, so it can have a negative effect on the weld in terms of strength. Also, since mill scale has a higher melting temperature than steel, you may not input sufficient heat into the metals and as a result, the steel component will not fuse.
There are ways to chemically remove mill scale with the safest way being soaking the part in distilled white vinegar for 24 hours. This works great for smaller parts. However, the quickest and easiest way to get the mill scale off the steel is to use an angle grinder with either a wire wheel (if the layer of mill scale is fairly thin) or sanding flap disc. When going the route of a flap disc, keep in mind the grit. A coarser grit disc will take off the mill scale faster but leave grinding marks in the steel. If you’re after a smooth surface finish in the end result, progressing through the grits until you reach the desired finish will be required. When grinding on your material, it’s crucial to safely hold it in place. A vise can work great for this, but sometimes it’s easiest just to grab something like a BESSEY F-style Clamp and hold it tight to a workbench. BESSEY has F-style clamps that can range from 600 to 5000 lbs of clamping force, but for this application, you only need enough clamping force to hold the part still, so a light duty clamp is absolutely capable of doing so. The last thing you’ll want to do after grinding off all of the mill scale is to wipe down the steel with some acetone.
Cutting to Size
Getting the steel cut to size is not any different than how you would get lumber for a woodworking project cut to size, the tools are just slightly different. If all you have is a hacksaw with a bi-metal tooth blade, you’ll be able to get the job done just fine. However, one of the most indispensable tools when it comes to metalworking is the angle grinder and an abrasive cut-off disc. This was one of the first metalworking tools we got in our shop, a cheap harbor freight corded angle grinder and it is still in use today. There are various angle grinder attachments that’ll give you a lot of options while working with metal: Grinding wheels, sanding flap discs, cutting wheels, wire wheels.
An angle grinder with a cut-off disc is by far a very handy method for cutting the steel to size, but it’s not always the most accurate. One of our favorite tools to cut material to size is with the horizontal bandsaw. These have a vise built in that holds material still and often have a removable work stop for making repeatable length cuts.
Other methods for cutting steel involve introducing a little heat into the equation. An oxygen/acetylene torch delivers enough heat through its flame tip to cut through some seriously thick steel and a plasma cutting torch follows the same principle, just using electricity instead of a flame.
Drilling
Your project may need some holes drilled at some point and there are a few differences when drilling into metal compared to wood. The most important thing is to use a center punch to leave a little dimple where the hole will be drilled. This allows the tip of the drill bit to have a registration mark, ensuring it stays centered for the hole to be drilled. Without center punching, the drill bit will have a tendency to skate around on the metal, possibly drilling the hole in the wrong location.
Another important factor when drilling holes in metal is the speed or rotations per minute (RPMs) of the drill bit. In metal, you want the RPM to be much lower than it would be when drilling a hole in wood. This has an effect of the heat build-up in the drill bit. In addition to using a lower RPM, you’ll want to use some sort of lubricant to act as a coolant to extend the life of the bit. A spray of WD-40 works just fine, but there are various cutting fluids that you can drop a dab of on the hole before and even while drilling to keep the bit cooler.
The type of drill bit you use can also be a factor when drilling holes in metal. Titanium coated drill bits are fairly inexpensive and work just fine for drilling holes in metal, but you’ll notice over time that they dull more quickly. Our preferred type of drill bit to use when drilling holes, particularly in steel, are cobalt drill bits. Being made of cobalt, they have a higher resistance to heat, therefore stay sharper longer in comparison to bits made of other materials. We have a 29 piece set from Montana Brand Tools that we absolutely love. Cobalt bits are more expensive than other types of drill bits, but the longevity of the bit makes up for the up-front cost. You’ll end up spending more over time on say titanium coated bits. Another reason we love our bits from Montana Brand Tools is that they offer a life-time warranty on their bits. If one chips during use, they will replace that bit at no extra cost.
A handheld cordless drill that you may already have is definitely capable of drilling holes in metal, but a drill press is the way to go when it comes to ease and accuracy.
Joining Metal
Nuts and bolts can work just fine for holding pieces of metal together, but the far superior way to combine the pieces is by using a heat source to fuse them into one. Welding is what most people think of when it comes to the process of joining metal, but there are technically other processes that achieve the same outcome of combining multiple pieces into one. The definition of the process is based on the temperature required to combine the parts as well as the materials being joined together, and which one that is used depends on the strength of the bond required. For the sake of avoiding confusion in this lesson we’ll focus on welding, but for your knowledge; the different processes are welding, brazing, and soldering:
● Welding: the joining of like materials, (ex. steel to steel, aluminum to aluminum, etc.) It’s considered a weld when the base material melts and forms a homogenous piece, called a weldment. The melting point of steel is 2700℉ (1500℃), which is why the electrical arc given off from a welding machine, reaching up to 10,000℉ (5500℃), can virtually instantly join the pieces.
● Brazing: When the applied temperature is above 840℉ (450℃), but below the base material melting temperature. The pieces are held together with a filler metal that has a melting point within that temperature range. It acts as a sort of hot glue, flowing into the pores of the metal at a molecular level, making a mechanical bond. The process of brazing allows for dissimilar metals to be joined (ex. Steel to brass).
● Soldering: This process also uses a filler metal, but it is considered soldering when the applied temperature is below 840℉ (450℃), yet hot enough to melt the filler metal.
How to Keep Welds Accurate
Just as wood can warp with exposure to moisture, metal warps with exposure to heat. The intense heat applied when fusing pieces together causes the molecules in that area to expand and after rapidly cooling and contracting, the metal will develop a warp in it. The best way to combat excessive movement in the material is by applying enough clamping pressure to overcome the internal forces moving the metal, keeping everything lined up and in place. Our BESSEY clamps do a fantastic job of this, ensuring the parts turn out accurate and everything stays where it's intended to be placed.
The amount of movement in the metal is dependent on the thickness/mass of the material and how much heat is applied. Thicker material requires more heat for deeper penetration, therefore potentially having more movement. That’s where the amount of clamping pressure comes into play. The techniques used while welding can mitigate the amount of heat build-up in an area of the metal (i.e. tacking and jumping around where the welds are being placed. More on that in Video 2 of this series). So if your material is on the thinner side, using some BESSEY clamps that are designed for woodworking, such as their GSCC style clamps which can put out up to 600 lbs of clamping force, may be enough to keep things in place.
When the material starts getting thicker and requiring more heat to achieve good penetration, making a nice strong weld, you’ll want to apply some higher clamping pressure. That’s when we would recommend moving into BESSEY’s all steel clamps. For example, their GSM classiX® series all-steel clamps can put out up to 2660 lbs of clamping force, plenty enough to keep things in place.
One great investment when it comes to getting repeatable, accurate parts welded together is a welding fixture table. These tables have accurate holes placed on a grid pattern where stop blocks can be placed to lay out a pattern for positioning components to weld together. There are also clamps where one end is a precision size pin that inserts into any of the holes on the table. Lincoln Electric has a great portable folding fixture table that you can combine with some of BESSEY’s fixture table clamps to easily hold parts in place. They have clamps with a fixed throat depth and even ones with a variable throat depth that allow for greater flexibility when fixturing components. For even faster securing of material, BESSEY has horizontal auto-adjusting toggle clamps that attach to a toggle clamp adapter plate that keep a low profile, making it easier to maneuver around when welding. While a fixture table isn’t 100% necessary when starting out, we’d highly recommend one for a more efficient work-flow, especially if you don’t currently have a metal surface to weld on.
Our Recommendation of Equipment to Start With
A question we often get is “what do I need to get started with metalworking?”. Some things you may already have as a woodworker, and you can use them in your metalworking projects, but here is a list of our recommendations to products from companies we trust or items found on Amazon to begin your metalworking journey. Clicking on the link for each item will bring you to either the product on the manufacturers website or our Amazon storefront where we curated a list of options. Disclosure: some of the items listed in the Amazon idea lists we have not personally used, but feel they are a quality option for the price.
○ Hearing Protection (ISOtunes is our preference, our link saves you 10% )
○ Flap Discs (recommend getting multiple grits, start with 36, 80, and 120)
● Vises
Starting out, we’d recommend a bench mounted vise and a drill press vise. This list also includes other specialized types of vises for specific applications.
One of our favorite tools that have many uses are MagSwitch products. These are some of the ones that we highly recommend looking into (using the link saves you 10%):
● Other Useful Power Tools
This list of products are a suggestion of what we think are useful when it comes to getting started with metalworking. Not everything on this list is 100% necessary. As you venture further into more metalworking projects, you will discover things that may help make the job go quicker, more efficiently, or even safer. These links are all affiliate links, so if you do use them to purchase any products, we want to sincerely thank you for the support! In addition to the links above, there are some additional brands we are affiliated with, some who offer discounts when you use our code! You can find a list of those brands and discount codes on our website by clicking the link here.
Again we want to thank you all for the support and hope that you find our metalworking series here on The Maker Collab University helpful! We’ll see you in the next video! Cheers!
Priscilla & Luke
Comments