Tight Fabrication Tolerances Are Often Unnecessary and Always Expensive
Ah yes, the title block at the bottom of the print clearly spells it out: +/- .005 fabrication tolerances for anything with three decimal places…and every dimension on the print goes out three places!
But (there is always a but) how many engineers and designers realize that one little box at the bottom of their print—usually from a default template—can drastically change the cost of their designed part?
Speaking about metal fabrication specifically (not machining), tolerances as tight as .005 can be very arduous and many times completely unnecessary.
Unfortunately, many engineers design these constraints into their work unknowingly, which nearly always leads to significantly higher priced parts—sometimes as much as double.
Engineers should consider that metal fabrication shops work with cutting, forming, sawing, punching and welding—all these processes are a far cry from milling, lathing, drilling or boring.
Fabricated parts are usually assembled with fasteners and welds while machine parts are assembled with pins and intersecting pieces—consider, as a simplistic example, the difference between a vehicles metal frame (fabricated) versus the vehicles intricate engine block (machined).
Very simple engineering modifications can help parts and assemblies work without requiring mind-bending fabrication tolerances. Holes, for example, can be slotted or oversized.
On paper the difference seems minimal. That is not true. Most fabricating estimates start right at the title block as estimators check to see what tolerances are required for a successful part. The tighter the tolerance callouts, the more expensive the part will be!
Nearly any professional metal fabricating company would be excited to work with customer engineers and quality teams to collaborate on design tolerances that make sense. Take a few minutes to contact All Metals Fabrication and discover how a few small changes could save your company real money and time.
Tube Laser Work in Real Life
AMF recently won a job from a very significant customer with a worldwide footprint. They wanted approximately 150 each of these vanity support brackets (see drawing) and requested a price.
When we gave them our bid they were surprised at the price. Too low, they thought – and they wanted to be sure we had everything covered. (We did!)
The part is designed for angle iron but because of the 10 EA holes that need drilling into the angle (a major pain in the booty) the customer is willing to concede making the part from flat sheet metal and break-forming the bend. (See Highlight #1 on the print)
Still, they are asking for the edges to be ground smooth—actual call out is a 1/8-inch radius. (See Highlight #2 on the print)
The buyer and engineer have been trained over the years by fabricators that this part would be easier to make from flat sheet metal than angle iron. (That training needs to be re-done, and new possibilities need to be considered!)
With the tube laser, none of these issues exist!
• Tube lasers can cut angle iron easily.
• Tube lasers can cut hole or slots into the angle iron flanges easily (and very accurately!)
• Tube lasers can miter the 45-degree joint easily, while simultaneously chamfer the cut prepped for welding with its 5-axis cutting head.
This is a relatively simple part even with the workaround – but the point is that real-world tube laser technology takes a simple part and makes it even simpler AND less expensive.
Think about it.
Stop for a minute and consider what simple parts can get even simpler with this technology, and you are just scratching the surface of what can be done! Our expert metal fabricators can bring your next project to life. Contact us.
Tube Laser and Welding Technology – How They Work Together
All Metals Fabrication was founded in 1994 and since then, we’ve been a top-tier metal fabrication company. Our two core markets are industrial metal fabrication and architectural metal fabrication. As industry experts, we specialize in fabricating all types of metal including steel, stainless steel, aluminum, copper, brass and more.
Tube Laser Technology
Advancements in tube laser technology have significantly reduced welding and assembly times. Here at AMF, our Mazak Fabrigear II 220 gives us the ability to cut tube, pipe, angle, bar, beam and more in rapid time and with incredible precision. Our customers and even our own internal welding crews have been surprised and thrilled by the incredible benefit, especially when it comes to the downstream assembly of materials – we’ve discovered that welded assemblies happen about 30 to 40 percent faster. For example, a normal assembly that may take an hour to weld can be fabricated with tube laser technology in 35-40 minutes, and two-piece cut can nestle up without so much as a finger to hold them together.
Extreme heat from welding metals together can reach temperatures above 2,500 degrees Fahrenheit. It’s basically melting pieces of metal together. That much heat can distort and warp materials so it’s important to take steps to avoid over-welding, especially if you like straight, square and well fit assembly of parts. Learn more about All Metals Fabrication’s welding processes here.
And here’s how we use tube laser and welding together:
How do you turn 3-inch square tube into a rectangular tube with an integral formed corner? Use a tube laser and some skilled welding! This part that Justin is showingin the photo below started out as 3 x 3 x 0.125 steel tube. A little presto magic on the tube laser with some welding and we ended up with a rectangular shape tube tapering from top to bottom and through a formed end.
The combination of welding and tube laser technology yields endless possibilities—structurally, architecturally, and mechanically. More and more we’re seeing engineers and designers incorporate tube laser technology into welding projects.
• Dedicated 60’ Tube Lasering
• Flat Sheet Lasering
• Water Jetting
• TIG and MIG Welding
Call us today to learn how All Metals Fabrication can make your next project a reality!
All Metals Fabrication Projects: What We’ve Been Creating in 2017
Wondering what we’ve been up to this year? Check out All Metals Fabrication Projects!
Utah Jazz Practice Facility
The Larry H. Miller Group and Utah Jazz asked All Metals Fabrication to fabricate another decorative metal hood for the Utah Jazz Practice Facility. This one was their biggest yet, spanning over 20-feet tall with a 24-inch diameter trunk and 72-inch x 48-inch oval base.
Utah Performing Arts Center and All Metals Fabrication putting on a show!
Prime Insurance wanted a staircase with a wow factor, and we delivered. This complex stainless steel helical staircase features aircraft mesh, .750 thick glass, and quality craftsmanship that had our customer very happy. Upon completion, Prime Insurance said, “Our objective to wow visitors was accomplished! We highly recommend AMF to anyone in need of high-quality customer metal fabrication.”
Aluminum Staircase at SOJO Station in South Jordan
Photo by Chase Young
Jackson Elementary Benches
All Metals Fabrication was a proud participant in fabricating these benches for Jackson Elementary School, along with FFKR Architects and 3Form. The benches for this volunteer project were designed by the students to look like pencils!
University of Utah Tube Laser Project
All Metals Fabrication recently completed a very challenging job at the University of Utah. Aluminum panels were cut, formed and installed for a great looking building facade. Craftsmanship, technology, ERP planning and quality work all on display!
Speaking of tube lasers…
We used our Mazak Fabrigear II 220 to cut 3-inch double-X pipe with a wall thickness of nearly 3/4-inch thick!
Here’s a peek at some recent metal fabrication detail work
And a few shots of the AMF team in action
Give us a chance to ‘prove our metal’!
Contact us with your big idea and we’ll get started on your metal fabrication project!
Why Small-Sized Channel Forming Can Be A Challenge
Customers are often baffled by an over-the-phone explanation of why certain sized channels cannot be press brake formed. Although press braking appears to be a simple concept, precision accuracy can be quite difficult.
There are a couple of reasons for this but the most significant reason is best illustrated by Figure 1.
If the channel has vertical legs that are too long when compared to the base, the leg formed first will crash into the forming dies before the second bend bottoms out at 90 degrees.
When that happens the metal will crash into the brake or forming dies and the legs or base (or both) will be stretched and contorted, which basically ruins the channel.
Sometimes these constraints can be overcome. Here are some suggestions when forming small-sized or deep-leg channels:
- Custom “dog leg” or “gooseneck” or “swan neck” dies (shown in Figure 2) can often be used or special ordered that allow for tighter formed channels.
Most metal fabricators will have a few sets of standard gooseneck dies for basic channel forming but often times custom sets of metal forming dies will have to be ordered to form and fabricate the parts needed.
These types of dies are expensive, costing several hundred dollars per foot so smaller-sized jobs, particularly non-repeat jobs, are often not quoted because of the excessive cost of purchasing a custom die set.
- Some fabricators will suggest “back-bending” the metal channel, which is also hard to explain verbally but can be attempted.
Back bending works by creating a “W” shape in the formed part and then hitting the channel again with a flattening die to smash the middle section out of the “W” (See Figure 3).
Back bending (see the green shape) keeps the leg of the die from smashing into the crash-point as shown in the illustration. This works well when there may be only a few parts to bend and the fabricator and customer decide, jointly, that it makes sense.
There are a few drawbacks to this method.
One, the metal part will have a line down the middle of the channel where the metal was flattened, which may or may not be important depending on how the part is used. (See red triangle in Figure 4).
Two, this is not a very efficient way of forming parts because it takes several press brake setups and multiple handling of parts compared to basically one set up if the part was formed with the gooseneck dies shown in Figure 2.
All of this is simply to say that forming small or deep channels in sheet metal, as we originally pointed out, is not as easy and obvious as one might think.
Hopefully, this will help you as you work with your local metal fabricator.
Future metal fabrication and press brake forming topics that relate to this will include forming fractures (when metal actually fractures or breaks as it is formed), minimum forming dimensions (what is too small to form) and forming to inside or outside dimensions.
Sheet Metal Fabrication and Ironwork: What’s the difference?
It may seem that sheet metal fabricators and ironworkers have similar jobs. Both are highly skilled trades but they actually have different skill sets and utilize different tools and materials. Typically, ironwork is more structural and sheet metal fabrication is more functional. Both types of metal fabricators work with a variety of metals, machinery and equipment.
Historically, ironworkers fabricated with wrought iron, but today’s skilled craftsman work with a variety of ferrous and non-ferrous metals on heavy-duty projects. There are three main types of ironworkers.
- Structural ironworker
- Ornamental ironworker
- Reinforcing ironworker
As you might guess, structural ironworkers erect the framework of bridges, buildings, stadiums, amusement park rides, bank vaults and other large-scale industrial metal projects according to engineer blueprints. They may also load and unload equipment, operate hoists and forklifts, place pre-cast concrete slabs, and perform industrial maintenance.
Ornamental ironworkers, or finishers, are responsible for the more architectural metal metal elements such as window frames, stairways, catwalks, railings, fencing, gates and building entranceways. These projects can be fabricated from a variety of different types of metals and are usually welded or bolted to the main structure. Ornamental ironworkers are highly skilled at arc welding.
The main job of reinforcing ironworkers, a.k.a. rodbusters, is to strengthen structures. These are the workers who place and tie rebar, and reinforce concrete footings, slabs, bridge framework and building structures.
Some people say the biggest difference between ironworkers and sheet metal fabricators is the height they work from the ground!
Sheet metal fabricators
These skilled tradesman frequently work in metal fabrication shops or at manufacturing plants. They may specialize in fabrication, installation or maintenance, but may perform tasks in all three areas. Sheet metal workers may fabricate metal roofs and rain gutters, heating and cooling systems, handrails, auto parts, and more. There are as many types of sheet metal as there are types of metal, including aluminum, steel, stainless steel, zinc, copper and a variety of alloys. Sheet metal fabricators take into consideration metal thickness, tensile strength, manufacturing method and quality.
All Metals Fabrication in Utah is an industry expert, working with all types of steel, stainless steel, aluminum, copper, brass, composites and other metals. Our methodology is focused on supporting each client with estimating, engineering, project management, shop fabrication and field installation. Contact us to learn how we can make your project vision take shape.
The Lowest Bid: Why Cheaper Isn’t Always Better
We all want the best value for our money. But when it comes to metal fabrication, especially large-scale construction projects, the lowest bid doesn’t necessarily always provide the best value.
All Metals Fabrication President, Rich Marker, tells the following story. “Years ago, when we were building our first house, we needed a mason to put up a rock wall. My contractor found three bids. We saw the lowest bid and figured it was $3,000 below our budget (heck yes, we thought, that will allow us to get heated tile in the bathroom).
What we were sad to learn, after the job was installed and bills were paid, is that the installation crews had dumped all their extra plaster-mix into one of our flower beds (which we had to completely dig out). They also wiped their trowels on our decorative landscape rocks, which I still have not completely fixed and now, ten years later, some of the rocks are falling off our house—worst $3,000 dollars I ever saved.”
As hard-working consumers, it’s a challenge to turn our back to the lowest bid. The biggest question to ask, however, is whether the lowest price is really the lowest price?
The Lowest Bid
The lowest bid is often a result of a bidders mistake—scope items may be missed, complexities may be underestimated or, worst case, craftsmanship may be undervalued. Any or all of these issues can lead estimators down a slippery path.
Ultimately—and particularly when quality is at stake—the lowest bid almost always leads to other hidden costs that present themselves when it is too late to change. Some of those include the following:
• Sloppy workmanship that leads to poor appearance.
• Poor craftsmanship that leads to failing outcomes (often times just past the warranty period).
• Slow or improper work that hinders other trades and slows the overall project down.
• Wasted management time trying to get poor performers up to speed.
We urge contractors to take more initiative with their customers to find sub-contractors that provide great craftsmanship, on time delivery of materials and goods, and effective project management infrastructure.
The combination of these strengths allows the buyer to race to the finish line with confidence rather than the opposite which is full of stops, starts, bumps and bruises.
No company is perfect, but high-quality companies make extra steps to overcome mistakes and, even more, prevent them from happening again. They learn and grow as each project runs its course rather than just muscling through each job for the check at day’s end.
Don’t Assume All Fabrication Companies Are Equal
Price quotes can vary for a multitude of reasons, and so can a company’s experience. When it comes to metal fabrication, and especially large-scale projects, you want the most qualified company for the job. A lesser-experienced company will often present a lower bid, and that inexperience is often reflected in lower-quality materials, shoddy workmanship, safety oversights and, ultimately, in the final product.
All Metals Fabrication has decades of industry experience serving both industrial and architectural fabrication of every size and scale. We strive to be the absolute best by amazing our customers with impeccable value, high-quality materials and craftsmanship. Our culture of improvement, team work, recognition, hard work and integrity creates a working climate that ultimately provides our customers with the best products and value possible.
Learn more about our methodology and how our talented team of engineers, project managers and fabricators work together to bring you the best. Give us a call at 1.877.433.1888 to get started.
3D Printing’s Impact on the Metal Fabrication Industry
The potential for technology to change the way the metal fabrication industry operates is ongoing and enormous. We’ve already benefited from laser technology with faster, more accurate metal fabrication. As 3D printing evolves, it will also have a big impact on how things are manufactured.
Also known as additive manufacturing (AM), 3D printing is changing the face of manufacturing and production when it comes to just about every industry: automotive, electronics, military, even food. Originally used with plastics and polymers, recent innovations include a type of 3D metal printing as an additive process that uses a laser beam to melt micron layers of metal powder instead of plastic filament. New 3D printing machines will allow for using a wider variety of metals, which will simplify the printing process.
Industrial Fabrication and Manufacturing
The evolution of 3D printing has gone from a product development tool to a full-blown industrial and manufacturing tool. Metal additive manufacturing will lead the way with processes such as metal binder jetting, powder bed fusion, and directed energy deposition.
Mass manufacturing faces the biggest challenges when it comes to 3D printing, but rapidly evolving technology will eventually allow production speed and quantity to increase. Some experts predict a complete disruption in traditional manufacturing in many industries.
In April 2017, a Massachusetts startup announced the release of two new metal 3D printing systems targeted toward the engineering and manufacturing industries. Initially allowing engineers to make metal prototypes, the full production system rolling out in 2018 will enable manufacturers to print metal parts. The system uses powdered metal and a “bound metal deposition extrusion process, which it says creates repeatable, high-resolution parts that are superior to not just current printed parts, but also parts made from traditional casting.” (Forbes)
In traditional fabrication, there’s often wasted materials. With 3D printing, waste and energy use can be reduced. 3D printed products also have the potential to be lighter, a big benefit especially in the aerospace and aviation industries.
One of the coolest anticipations is the ability to use 3D printing in zero gravity. Astronauts will eventually be able to print parts, tools, and possibly even food in space, helping make space missions more self-sufficient.
All Metals Fabrication is watching this technology carefully, anticipating the day will come when we add this capacity to our manufacturing base.
Welding Metals Together Will Create Warping and Distortion
Warping and distortion when welding metals is a topic we have discussed before but it seems to be one of the biggest overall issues that our customers misunderstand.
Welding metal materials is not “gluing” pieces of metal together, although that is sort of how it seems.
Welding is basically melting metals together—for steel, those melting temperatures, without getting overly technical, range at approximately 2,500 degrees Fahrenheit.
The color of the metal, during the process, will give a good clue to just how hot the joining metals become. Bright yellow and you are over 2000 degrees. Red is around 1200 degrees.
Most people might naturally begin to understand that introducing that type of heat, along with rapid cooling, is a recipe for warping and distortion.
There are ways, of course, to mitigate warping but sometimes, particularly fabrication assemblies that have high dimensional tolerances (or aesthetic tolerances for architectural designs) the engineers or designer may be asking for something that is nearly impossible.
So, some steps to help minimize distortion when welding metals include the following:
1) Avoid Over Welding—this is a big one! Solid, thick welds look pretty but can warp the heck out of metal particularly on thinner materials.
2) Use Intermittent Welding whenever possible—this is commonly referred to as stitch welding. It allows for parts to have little segments of weld rather than continuous welds.
3) Well-planned Weld Sequences—this process allows for welding along different segments of the assembly so all the heat does not collect in one point for a long period of work.
4) Clamping and Jigs—locking parts into place while welding is the most commonly used method of minimizing warping but it is not a fix-all. Parts will often move once they are removed from the clamps (hopefully not as much as if they were welded in free form).
5) Allowing for Warping—which means presetting the parts anticipating that they will move or warp, hopefully into place.
Metal welding is not a new trade—craftsman have been mastering this work for years and can do amazing things…sometimes impossible things. Still, there are limits. Engineers and designers would be well served to consult industry experts as they design and detail parts to make sure they are, in fact, workable and weld-able!
Laser Cutting Plastic-Type Materials
AMF is often asked about the feasibility of laser cutting materials other than metal.
Truth is lasers do a good job of cutting nearly anything but it isn’t that simple particularly when it comes to plastic.
Cutting certain types of plastics can cause significant caustic fumes that can literally be lethal if someone is exposed in a major way.
Of course there is science behind this. Without getting into the chemical specifics, common plastics can be divided into two categories: Thermosets and Thermoplastics.
These two categories are delineated by how much chemical bonding takes place inside the plastic material itself.
Thermosets have a large amount of bonding connections and break down easily when heated because they are less subject to melting or puddling.
Common example of Thermoset plastics would include: Rubber and Epoxy Resins
Thermoplastics have fewer bonding connections and are a bit harder to cut as they tend to melt. In fact cutting is accomplished by a term called “melt shearing”.
Common examples of Thermoplastics would include: Polypropylene, Polyethylene, Nylon, PVC, Lexan and Acrylic.
The quality of the cut can be an issue. Often times the plastic will discolor at the edge of the cut with a brown charring effect. In addition to discoloration, some plastics will not cut cleanly but will, instead, melt at the edge leaving a poor quality (almost a drippy-looking) cut edge.
Cut discoloration and edge quality are certainly important factors but perhaps the most significant overall factor is safety. The ‘melting’ and heating impact of the laser beam cutting through the plastic creates fumes and gases.
Some of these fumes are merely unpleasant to smell, but some fumes can be very caustic and, as mentioned at the onset, can be utterly lethal.
Smokey and stinky materials include the likes of common rubber (think smoking tires on the road) and lexan.
Toxic materials include plastics such as Delrin, Vinyl and PVC.
PVC literally will create Hydrochloric Gas Vapors!
The takeaway here is that AMF’s tube laser will not be cutting PVC pipe. We generally try to avoid most plastics in general but do cut, from time-to-time, materials like Plexiglas near the end of the day when the shop can avoid the stink-out.