Custom Flat Bar Holes: CNC Plasma Cutting
Custom flat bar holes using our CNC plasma is a relatively easy process compared to the alternatives like drills or punching.
Unlike drilling or punching though, you have to keep in mind that there is a slight kerf with plasma cutting that becomes more pronounced as the material thickness increases.
What is kerf? Basically, the plasma cuts at a slight inner angle, which means the hole at the “top” is perfect to spec but the hole in the “bottom” of the flat bar is slightly less in diameter, so this must be accounted for.
How? Well, make the top hole a bit bigger than spec so the hole at the bottom is the right size, as mentioned before, there is no perfect process.
Of course for some projects we do at CNCROi.com, kern is actually a great and wonderful thing, such as my Star Trek Bat’Leth
For this specific application, the customer is in the mill working industry, as such, they needed a support method to hold an island extension, and quarter inch 6 mm thick flat bar is really a wonderful solution that gives incredible strength.
I’ve been doing metal projects for a long time, but it wasn’t until recently that I began making stuff for around the house and shop using it between jobs at CNCROi.com.
As CNCROi.com‘s CNC plasma is cutting a very narrow quarter inch 6 mm hole into the flat bar, there is a bit of dross on the top but this is easily chipped away.
As for precision, there was two ways of doing this job, the first, buying a sheet of quarter inch 6 mm thick mild steel and cutting out the holes THEN cutting out the flat bar “shape” OR, what I suggested to the customer, just get flat bar, make measurements and cut by eye.
Flat bar is one of those materials in metal working that’s abundant anywhere and everywhere, as a result, the cost is pretty close to wholesale as it gets, while sheet materials are worth more, by going the flat bar route, my CNCROi.com customer did save a substantial amount of money.
Whether it’s mild steel, cold rolled or hot rolled, stainless steel, titanium, brass, copper or what have you, all metal cuts and CNCROi.com can cut them all.
Of course, savings come at a cost, and that’s absolute precision, by eye, I’m maybe off 1-2 mm in any given direction when it comes to cutting holes in the flat bar but you have to remember this application.
These flat bars will go under a countertop, out of sight, so being a little bit “off” will never be noticed and do not affect the end esthetics, strength or value of the finished piece in any form.
If these flat bar holes were meant for a rocket ship, we’d choose the more expensive router and probably waterjet cut them out to account for any slight hear warping but for this application, even using a CNC plasma was overkill spec wise.
The applications for metal are endless, I’m also teaching myself to weld after attending a welding school in order to improve my skills in that department.
When it comes to hot rolled mild steel, our 85 amp Hypertherm Powermax85 cuts through this like butter, it’s an amazing sight to be seen, especially after years of drilling holes using a drill press in mild through stainless steel.
One of the first things I upgraded on my CNC plasma cutter at CNCROi.com was adding LED cross-hairs, it’s such a simple yet very powerful thing and I use it very often for projects just like this where the customer needs something quick, cost effective and where precision isn’t as critical a need.
You’ll noticed for the holes I marked, not only did I measure them out and added an “X” but also a big round circle, why? Because I don’t want to spend my time looking for a small X, big circles stand out a lot more.
If you are looking for something to get cut, regardless of size, design, material or spec, contact CNCROi.com right now!