General welding questions that dont fit in TIG, MIG, Stick, or Certification etc.
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Timberjack
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    Thu Jul 30, 2020 10:06 pm

Been watching guys on you tube using them ,im slow at catching up , but was wondering a good brand , and best commonly used sizes? any comments appreciated, ebay, amazon , ace hardware brands it dont matter.
Spartan
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    Fri Mar 06, 2020 8:59 pm

I use them very rarely, and usually only for sheet metal when needed (maybe 16ga., absolute max). They're quite handy for this. Usually have a wide and a narrow one on hand, so perhaps 1" for the wide, and 1/2" or so for the narrow. I think I got the most recent ones from the local big-box hardware store. Couldn't even tell you the brand.
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    Sat Feb 17, 2018 10:10 pm
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They are awesome for sheet metal, especially larger sized holes. Very hard to get a neat 1/2" hole or bigger in 14 guage sheets.

Depending on the specific bit you can use them on thicker as well. I use some of mine on 10 guage all the time. I usually is a 1/8" pilot drill first, as the step bits usually don't start very well and I didn't want to dull the point. So I start with 1/8, then the step bit will enlarge it up to 1/2" almost as fast as you can push it. Im a big fan of those bits.

I use Lenox Varibits. Bit pricy but I figured buy once cry once. I've drilled a lot of holes with em, they hold up well.

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BugHunter
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    Sun Apr 19, 2020 12:54 pm

Even the ones you pick up at Harbor Freight for next to nothing are awesome for working in sheet metal.

A common mistake I see people make with them is they start with a small hole and the drill running relatively fast and then as the hole gets bigger they don't slow the drill down. When you get up to 1 inch diameter you've got some serious surface speed at say 900 RPMs. You really need to slow your drill down so you don't overheat the bit and wreck the cutting-edge. Even at half inch you probably shouldn't run them past 500 RPMs.
Ballistic308
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    Fri Jul 12, 2019 10:56 pm

I watched this a couple of months ago. This is a great relative comparison.


https://youtu.be/nGbMQul6_Bc
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    Mon Sep 03, 2018 3:35 pm
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Step drills are great, they make round holes in thin material without a lot of effort.

We usually buy Irwin cobalt step drills. They are pricey, but you can use them a very long time if you use a little coolant and don't burn them up with excessive rpms. Good for up to 1/8" material and you can get a wide variety of sizes out of a couple tools. I usually pre-drill a 3/16" hole to save the split-point of the step drill for when it makes sense to use it.
https://www.mscdirect.com/product/details/82688789


If you're making a specific hole size I also recommend annular cutters.
https://www.mscdirect.com/product/details/98380892
annular cutters.JPG
annular cutters.JPG (54 KiB) Viewed 1753 times
I bought this tool to make a 17/32" dia hole in ststl tubing which isn't a size available on any step drills.
Super clean holes in 1 shot, no pre drilling or extra material removed. Pretty impressed how well it worked, super efficient cutting tool.

These links aren't the best pricing out there, but they were easy to find and share.

- dudley
Poland308
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    Thu Sep 10, 2015 8:45 pm
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    Iowa

It’s a step drill. There are no exact sizes. They work great but there rough in only.
I have more questions than answers

Josh
motox
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    Thu Nov 28, 2013 12:49 pm
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    Delaware

if you want really clean close tolerance round holes you margin or double margin drills.
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