Author Topic: Drilling a large hole without a drill.  (Read 1996 times)

Offline airmodel

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Drilling a large hole without a drill.
« on: June 11, 2014, 05:59:58 AM »
Hi everyone

I recently needed two 35mm holes in perspex. As large drills are expensive I made a boring bar to be held in a chuck. A pilot hole is drilled to stop the boring bar from wandering off center. The boring bar needs to be a neat fit in the pilot hole. I have used this method  on aluminium and steel. If used on metals a very slow speed is used and also plenty of coolant/cutting oil are needed to help the cutting action.

The photos and video show how it works.   http://youtu.be/Mr6hTa7z_AI

Offline Thor

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Re: Drilling a large hole without a drill.
« Reply #1 on: June 11, 2014, 06:16:15 AM »
Nice job, I have always drilled such holes with a holesaw.

Thor

Offline smfr

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Re: Drilling a large hole without a drill.
« Reply #2 on: June 11, 2014, 04:45:51 PM »
Interesting video! I didn't realize that it was so easy to repurpose a microwave oven controller board.  :ThumbsUp:

Simon

Offline Johnmcc69

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Re: Drilling a large hole without a drill.
« Reply #3 on: June 11, 2014, 05:09:32 PM »
I'm with Simon, that's slick!

 What are you going to use this on?

 John

Offline b.lindsey

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Re: Drilling a large hole without a drill.
« Reply #4 on: June 11, 2014, 07:05:23 PM »
Very slick...and a nicely done video too!!

Bill

Offline PStechPaul

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Re: Drilling a large hole without a drill.
« Reply #5 on: June 11, 2014, 08:07:08 PM »
Pretty good! The power control could be used for something like a heater where there is a lot of thermal inertia and a slow PWM works fine. The PCB in a broken CFL is quite useful as well, as it will drive a 10-15 watt fluorescent tube more efficiently than old style ballasts:
 
<a href="http://www.youtube.com/watch?v=e7QJQBSBRCw" target="_blank">http://www.youtube.com/watch?v=e7QJQBSBRCw</a>

Offline airmodel

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Re: Drilling a large hole without a drill.
« Reply #6 on: June 12, 2014, 04:21:12 AM »
I plan to use it on my vacuum cleaner as a blower for my melting furnace. Before I made this housing it was in the open slapped together with live wires exposed. Now I can use it safely without getting zapped!