Intermediate sized holes, how to make them (what tool)?

When I made a collet rack the hole saw cut the holes right at 1 1/4 size.
problem was I could not get the collets in and out with ease. I had to take a hand grinder to each hole to open them up a bit. So if I had to do again I would use a adjustable trepan tool and make the hole a little bigger.
It was as much work to open the tight holes as to make them in the first place.
Jim
How thick was your collet rack? These collets seem to be slightly under 1.25. (Far eastern origin) I'll watch out for sizing, thanks for the warning. Hoping that with only 1/8" thickness, it won't be too bad.
I just went to eBay and they have a 5c collet rack tht holds 30 5c collets for $14.99
with free shipping.
Or you can buy a annular cutter for more than twice That amount and do the work your self.
And fits in my tool drawer? I looked at a lot of racks, didn't see something that would fit in the drawer efficiently. I have 33 collets right now. Besides, where's the fun in buying when you can make your own? Am I in the right forum? :D
 
How thick was your collet rack? These collets seem to be slightly under 1.25. (Far eastern origin) I'll watch out for sizing, thanks for the warning. Hoping that with only 1/8" thickness, it won't be too bad.

And fits in my tool drawer? I looked at a lot of racks, didn't see something that would fit in the drawer efficiently. I have 33 collets right now. Besides, where's the fun in buying when you can make your own? Am I in the right forum? :D


After being a machinist for more then 60 years I like to make things I can’t buy for cheap. Look at my avatar closely. It is made out of one piece solid cube with 3 free floating balls inside cube . The balls are .125 bigger then the entry holes. So they can’t be pressed into cube. And I hand made all the form tools on a bench grinder and lathe. So I tried to warn you of some of the pit falls on making a collet rack.
And I think I am in the right forum.
 
Have to admit, I’d use some 1/8” plywood and a Forstner bit. But that’s just me.
 
You may need to smooth it out with a cartridge roll type sand paper.
 
Being the "cheap old buzzard" that I am, if I don't have the tool necessary for a job, I look around my stash until I find something that sorta-kinda would work. All of this is based on what I am trying to accomplish. I use a lot of sheet steel, both painted and "GalvaLume". And old electrical enclosures. And. . . Electrical enclosures use an 11 Ga back pan. At 0.118, I call it 1/8 "under". Actually 3mm but I still think in fractional inches.

For thin (<1/8") steel, I use a step drill to rough in the starter hole. Then use one of several devices, depending on how I feel at the time. The 30mm / 1-7/32 knock out on a step drill or a 1-7/32 knock out punch. I've used Greenlee's "30mm Slug Buster" for 1/8" stainless. With that material at electrical spacing it leaves a flat finish. I do use a hydraulic punch driver. At my age I'm not as strong as I once was. For aluminum up to 3/16" or so, I will use a hole saw or step drill. Knockout punches can leave internal cracks in the metal when you get into thicker sized material. As would an "Iron Worker".

Then there's drilling a number of small holes in a circle and smoothing up the edge with a file. Or a KO punch. Or. . . If I was in the field, the choices would be much less. It largely depends on the needed accuracy. Just how accurate do you "need" it to be. And how fast. If it's for "profit", it needs to be done yesterday. Which in turn justifies some fancy tooling to do one hole. Or if it's for an idea that may or may not work and time isn't a constraint, drilling a series of holes would do. It all comes down to time VS money VS later use of the tooling. There is a tool for virtually any job, if you look for it. How much do you want to spend?

.
 
Meow, meow, meow. Bought the annular cutter...

Have you tried it yet?

I use AC's in the mill (Bridgeport) all the time. I use slow speed and spray coolant. Wouldn't try a hand held drill:eek: or even less than a heavy duty drill press. Work needs to be secured!
Get the one you need and add to your collection as needed or buy a set and fill in with more. Once you try you'll like!!

My 2 cents
Aaron

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I always use a step drill for these kind of holes. The single flute step drills make really close to perfectly round holes. The 2 flute step drills cut faster and still make very nice very round holes. When I get to the step that is the diameter I need I push through to the start of the next step which does a really nice job of deburring the hole. Then I flip the piece over and debur the back of the hole with the same bit.

When I say the one flute bits make really nice round holes I mean I have used a single flute step drill to enlarge the hole of a circular saw blade without adding any measurable runout to the blade.


I can't phathom getting along without my step drills!!!!
 
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