I need to punch a hole in the side, about a half inch. Drill bits I have tear it out. It’s too thick for Knifes and razor blades, scissors etc. I’m thinking laser, but don’t have one.
I made 100 and need to make 200 more, I used a hole punch and slid the tube over a large wood dowel. That took a couple days and tough on my hands.
Any ideas.
It is a Mailing Tube, 6"L x 2" Diameter x 0.06 Wall Thickness

Thanks Dave

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What kind of drill bit did you use? Spade? twist? hole saw?
The method you used sounds like what I would have recommended.
Look at some of the hole punches further down the page here
http://www.brettunsvillage.com/leather/tools/tools.html

This might be a bit extreme for cardboard, but how about a chassis punch. http://www.harborfreight.com/knockout-punch-kit-91201.html

I have tried all the drill bits mentioned by Raven, they all tear out. Also my hole punch is from Harbor Freight, a real one in a 2 ton press(which I Have) may be a solution.

Part of your problem is that there is no backing support. I've done this kind of thing many times with flat stock, such as a square tube that needed a hole drilled in the side after it was already constructed. Trying to drill through will often result in tear-out.

You will need to find something that can be used as a support on the inside. Because you are dealing with a curved surface, you will need to find another curved surface that is a close in size the inside diameter as possible. A large dowel, a piece of PVC pipe, etc. In order to brace this, you will need to have a piece that will extend out both ends of the tube you are wanting to drill. Then, support these ends so the piece you are drilling only contacts the supporting piece inside.

I would use a Forstner bit on a drill press, as it will drill a cleaner hole. You can do this with a hand drill, but you'll have to be careful to keep everything aligned. I might also start drilling the hole before using the support, if it helps start the hole. Just don't go too far in until you have the support in place.

The more pressure of the piece against the support, the less chance of tear out. The last part of the hole before you break through should be done with as little pressure from the bit as possible. Let it cut away as much material as possible before breaking through.

Michael,
I do have a dowel that is just a little smaller in size. and I still get tear out.

Hey Dave,

https://www.youtube.com/watch?v=6ZjIonzpdGA&feature=youtu.be

If you don't have a router table, bring them by the shop one day and I will rout them for you.

Nick

Nick,
You are amazing. I just set up my router table and used PTFE for stop blocks, works great and very little tear out, about the same as a hole punch.

Thanks Dave

OK, that's awesome, Nick! I can make use of your idea.

Thanks guys, I am thrilled that I could be of some help!!!

Nick

A bit of masking tape on the inside may help with the tearout. It works well when cutting wood.